PORTAL_Engineering - Wikiparency

**Engineering** is the discipline of turning physics into machines that hold, move, cut, pump and last, and this portal is its front door on Wikitube: the mechanical-engineering spine of the microsim library, article face [[Engineering]]. Its core is [[Mechanical_engineering]] — the *Glossary of mechanical engineering*'s own vocabulary — run out from a loaded bar's stress and strain, through the machines that use that strength (gears, cams, linkages, belts), the vehicles and vibrations that ride on it, the heat engines and turbines that power it, and into the tolerances, meshes and materials a designer chooses to build it from. Thirty sections, thirty Main articles, one microsim per section. Sibling spine: [[PORTAL_Robotics]], which this spine crosses at fourteen points (a gear tooth is a joint drive; a bicycle model is a self-driving car's plant). Index: [[PORTAL_INDEX]] · hub: [[PORTAL_Centers_of_Excellence]]. **On the spine:** [[Engineering]] · [[Mechanical_engineering]] · sibling spine [[PORTAL_Robotics]] · hub [[PORTAL_Centers_of_Excellence]]. ## Part I — Forces and materials  *Microsims from the articles this section links:* <div class="wt-simrow"> <div class="wt-sim" data-src="https://wikitube-3d-microsims.netlify.app/Structural_engineering.html" data-title="Structural engineering"></div> <div class="wt-sim" data-src="https://editor.p5js.org/sciencenibber/full/f_RKf1JL_" data-title="Structural engineering microsim"></div> <div class="wt-sim" data-src="https://editor.p5js.org/sciencenibber/full/pgr6xBz-m" data-title="Aerospace engineering"></div> <div class="wt-sim" data-src="https://editor.p5js.org/sciencenibber/full/xTHeUaxph" data-title="Solid mechanics microsim"></div> <div class="wt-sim" data-src="https://editor.p5js.org/sciencenibber/full/ePuZ3ndUn" data-title="Strength of materials"></div> </div>  *Serves the [[Structural_engineering]], [[Civil_engineering]], [[Aerospace_engineering]], [[Solid_mechanics]] and [[Strength_of_materials]] shells.* Before anything is a machine it is a loaded member, and Part I is the mechanics of that load: the stress and strain a cut face carries, the linear law that ties them together while it lasts, the curve that describes what happens once it doesn't, and the four failure modes — bending, buckling, torsion, fatigue — that follow from asking too much of a beam, a column or a shaft. ### Stress and strain *Main article: [[Stress_(mechanics)]] · See also: [[Mohr's_circle]], [[Shear_stress]]* Cut a loaded bar at an angle and the force on that new face splits into a component that pulls straight across it (normal stress) and one that slides along it (shear stress); turn the cut and the two trade off in a fixed pattern that traces a circle in stress space. That circle, Mohr's construction, is a hand calculator's way of finding the worst cut — the principal stresses and the angle of maximum shear — without re-deriving the transform equations each time. <div class="wt-sim" data-src="https://wikitube-3d-microsims.netlify.app/engineering/Stress_(mechanics).html" data-title="Stress (mechanics)"></div> *Try: turn the cut angle and watch the point ride the Mohr's circle; then push the applied σx, σy and τxy and watch the circle itself move and resize.* Connects to: [[#Hooke's law and the spring|Hooke's law]] · [[#The stress–strain curve|Stress–strain curve]] · [[#Bending of beams|Bending]] · [[#Torsion|Torsion]] ### Hooke's law and the spring *Main article: [[Hooke's_law]] · See also: [[Spring_(device)]], [[Young's_modulus]], [[Poisson's_ratio]]* A spring's force grows in a straight line with its extension until it doesn't, and the slope of that line, the spring constant, is all Hooke's law needs. Stack springs in series and their compliances add; stack them in parallel and their stiffnesses add; either way the energy stored is the area under the line, ½kx². A loaded bar is the same law wearing different units — its stiffness is EA/L, its "spring constant" set by a material property (Young's modulus) and a shape. <div class="wt-sim" data-src="https://wikitube-3d-microsims.netlify.app/engineering/Hooke's_law.html" data-title="Hooke's law"></div> *Try: switch between the series and parallel spring stacks and read the combined constant; then swap the spring for a bar and watch the same line reappear with E and A in place of k.* Connects to: [[#Stress and strain|Stress and strain]] · [[#The stress–strain curve|Stress–strain curve]] · [[#Flywheels and inertia|Flywheels]] · [[#Vibration isolation|Vibration isolation]] ### The stress–strain curve  *Microsims from the articles this section links:* <div class="wt-sim" data-src="https://wikitube-3d-microsims.netlify.app/matter/Stress–strain_curve.html" data-title="Stress–strain curve"></div>  *Main article: [[Stress–strain_curve]] · See also: [[Yield_(engineering)]], [[Ultimate_tensile_strength]], [[Toughness]], [[Ductility]]* Pull a specimen past the point where Hooke's law stops working and the curve tells the rest of the material's story: a 0.2%-offset yield point, a rising engineering curve that peaks at the ultimate tensile strength, necking, and fracture, while the *true* stress — accounting for the shrinking cross-section — keeps climbing under the Hollomon hardening law the whole way. The area under the curve is toughness; how far it stretches before breaking is ductility. <div class="wt-sim" data-src="https://wikitube-3d-microsims.netlify.app/engineering/Stress–strain_curve.html" data-title="Stress–strain curve"></div> *Try: step through a low-carbon steel, an aluminium alloy and a cast iron and watch yield, UTS and ductility all move; toggle engineering vs true stress and watch the curve stop turning over at necking.* Connects to: [[#Stress and strain|Stress and strain]] · [[#Hooke's law and the spring|Hooke's law]] · [[#Fatigue and fracture|Fatigue and fracture]] · [[#Metal forming|Metal forming]] · [[#Material selection|Material selection]] ### Bending of beams *Main article: [[Bending]] · See also: [[Euler–Bernoulli_beam_theory]], [[Bending_moment]], [[Second_moment_of_area]], [[Deflection_(engineering)]]* A cantilever or a simply supported beam under a point or distributed load carries a shear force V(x) and a bending moment M(x) that both vary along its length; the bending stress at any point is σ = My/I, so the same moment hurts more the farther a fibre sits from the neutral axis. Change the cross-section — rectangle, I-beam, tube — and I changes with it, which is the whole argument for why an I-beam outperforms a solid rectangle of the same area. <div class="wt-sim" data-src="https://wikitube-3d-microsims.netlify.app/engineering/Bending.html" data-title="Bending"></div> *Try: move the point load along the span and watch the V(x) and M(x) diagrams redraw; switch the section from rectangle to I-beam to tube at equal area and read σmax fall.* Connects to: [[#Stress and strain|Stress and strain]] · [[#Buckling|Buckling]] · [[#Torsion|Torsion]] · [[#The finite element method|Finite element method]] ### Buckling *Main article: [[Buckling]] · See also: [[Euler's_critical_load]], [[Slenderness_ratio]]* A column loaded end-on doesn't fail by crushing until it's short and stout; a slender one buckles sideways first, at a critical load Pcr = π²EI/(KL)² that falls with the square of its length and depends on how its ends are held. Plot critical stress against slenderness ratio and the Euler curve only fits the slender end — short columns follow the Johnson parabola instead, and a small initial crookedness (an imperfection) rounds the sharp corner between them into the gentler curve a real column actually shows. <div class="wt-sim" data-src="https://wikitube-3d-microsims.netlify.app/engineering/Buckling.html" data-title="Buckling"></div> *Try: lengthen the column and watch Pcr fall with the square of L; switch end conditions from pinned-pinned to fixed-free and read the four-fold swing in critical load.* Connects to: [[#Bending of beams|Bending]] · [[#Tolerances and fits|Tolerances and fits]] · [[#Material selection|Material selection]] ### Torsion *Main article: [[Torsion_(mechanics)]] · See also: [[Torsion_constant]], [[Second_polar_moment_of_area]]* A shaft under torque twists by an angle φ = TL/GJ while carrying a shear stress τ = Tr/J that peaks at its outer surface — which is exactly why a hollow shaft, with its material pushed outward, resists as much torque as a solid one at a fraction of the mass. Watch a line drawn along the shaft's surface and it traces a helix as the shaft turns, the most direct picture there is of what "twist" means. <div class="wt-sim" data-src="https://wikitube-3d-microsims.netlify.app/engineering/Torsion_(mechanics).html" data-title="Torsion (mechanics)"></div> *Try: hollow out the shaft at constant mass and watch J and the twist angle both improve; raise the torque and watch the surface helix wind tighter.* Connects to: [[#Stress and strain|Stress and strain]] · [[#Bending of beams|Bending]] · [[#Gears and gear trains|Gears]] · [[#Flywheels and inertia|Flywheels]] ### Fatigue and fracture  *Microsims from the articles this section links:* <div class="wt-simrow"> <div class="wt-sim" data-src="https://wikitube-3d-microsims.netlify.app/matter/Fatigue_(material).html" data-title="Fatigue (material) · matter"></div> <div class="wt-sim" data-src="https://editor.p5js.org/sciencenibber/full/19WPH9qZj" data-title="Fatigue (material) · p5.js"></div> <div class="wt-sim" data-src="https://wikitube-3d-microsims.netlify.app/engineering/Fracture_mechanics.html" data-title="Fracture mechanics · engineering"></div> <div class="wt-sim" data-src="https://wikitube-3d-microsims.netlify.app/matter/Fracture_mechanics.html" data-title="Fracture mechanics · matter"></div> <div class="wt-sim" data-src="https://editor.p5js.org/sciencenibber/full/YcQoz_cJ4" data-title="Fracture mechanics · p5.js"></div> </div>  *Main article: [[Fatigue_(material)]] · See also: [[Fracture_mechanics]], [[Fracture_toughness]]* A load far below yield can still break a part if it's applied and removed enough times: the S–N curve (Basquin's law) plots the cyclic stress a material can survive against the number of cycles, flattening at an endurance limit for some steels and never flattening for aluminium. A nonzero mean stress eats into that allowance along a Goodman line, and Miner's rule adds up the damage fraction from a mixed load history one level at a time until it reaches one. A crack changes the question entirely — fracture mechanics asks whether the stress intensity K = Yσ√(πa) at its tip has reached the material's fracture toughness, no matter how far below yield the nominal stress sits. <div class="wt-sim" data-src="https://wikitube-3d-microsims.netlify.app/engineering/Fatigue_(material).html" data-title="Fatigue (material)"></div> *Try: raise the mean stress and watch the Goodman line cut the allowable amplitude; build a two-level load history and read Miner's damage sum climb toward one.* Connects to: [[#The stress–strain curve|Stress–strain curve]] · [[#Belts, chains and the capstan|Belts and chains]] · [[#Friction, bearings and lubrication|Friction]] · [[#Vehicle suspension|Vehicle suspension]] ## Part II — Machines and mechanisms *Serves the [[Mechanical_engineering]], [[Machine_element]], [[Automotive_engineering]] and [[Manufacturing_engineering]] shells.* A machine trades force for distance, or one kind of motion for another, and Part II is a catalogue of the six ways to do that and the four mechanisms — gears, four-bar linkages, cams, belts — built from them, ending with the flywheel that smooths whatever torque they produce. ### Simple machines and mechanical advantage *Main article: [[Simple_machine]] · See also: [[Mechanical_advantage]], [[Lever]], [[Pulley]], [[Inclined_plane]], [[Screw_mechanism]], [[Wheel_and_axle]], [[Wedge]]* Every machine, however complicated, is built from six elementary ones — the lever, the pulley, the inclined plane, the wedge, the screw, the wheel and axle — each trading a smaller input force for a larger output force across a proportionally larger input distance. An ideal machine trades force for distance with nothing left over; a real one loses some of the trade to friction, so its actual mechanical advantage always falls short of the ideal, an efficiency the sim draws as two bars that no longer match. <div class="wt-sim" data-src="https://wikitube-3d-microsims.netlify.app/engineering/Simple_machine.html" data-title="Simple machine"></div> *Try: step through all six machines and compare their ideal mechanical advantage at the same input force; then pull the efficiency slider down and watch the actual-advantage bar fall away from the ideal one.* Connects to: [[#Gears and gear trains|Gears]] · [[#The four-bar linkage|Four-bar linkage]] · [[#Belts, chains and the capstan|Belts and chains]] · [[#Hydraulics and pneumatics|Hydraulics]] ### Gears and gear trains *Main article: [[Gear]] · See also: [[Gear_train]], [[Rack_and_pinion]], [[Epicyclic_gearing]], [[Involute_gear]], [[Strain_wave_gearing]]* Two meshing spur gears, drawn to scale with their involute teeth, set a fixed ratio between the two shafts: the tooth-count ratio N1/N2 fixes speed and torque in inverse proportion and flips the direction of rotation. A single pair can't do a 1:30 reduction without an enormous gear, so a compound train splits it across several meshes instead — and a planetary train adds a third member, the carrier, that lets one gear set produce several different ratios depending on which member is held. <div class="wt-sim" data-src="https://wikitube-3d-microsims.netlify.app/engineering/Gear.html" data-title="Gear"></div> *Try: change the tooth counts and watch speed and torque trade off in the meshing pair; then switch to the compound train and watch a 1:30 reduction split across three meshes instead of one giant gear.* Connects to: [[#Torsion|Torsion]] · [[#Simple machines and mechanical advantage|Simple machines]] · [[#Flywheels and inertia|Flywheels]] · [[#The four-stroke engine|Four-stroke engine]] ### The four-bar linkage *Main article: [[Four-bar_linkage]] · See also: [[Linkage_(mechanical)]], [[Slider-crank_linkage]], [[Crank_(mechanism)]]* Four rigid links pinned in a loop trace a coupler curve that depends only on their four lengths; whether the shortest link can spin all the way around (a Grashof mechanism) or only rocks back and forth is decided by one inequality on those four lengths. The transmission angle — how far the coupler's motion departs from a straight push on the follower — is the practical measure of how smoothly the linkage runs, and most four-bars can be assembled two ways from the same four lengths, an ambiguity the sim shows as two coupler-curve branches. <div class="wt-sim" data-src="https://wikitube-3d-microsims.netlify.app/engineering/Four-bar_linkage.html" data-title="Four-bar linkage"></div> *Try: drive the crank around and watch the coupler point trace its curve; change a link length until the mechanism crosses from Grashof to non-Grashof and the follower stops making full turns.* Connects to: [[#Simple machines and mechanical advantage|Simple machines]] · [[#Cams and followers|Cams]] · [[#The four-stroke engine|Four-stroke engine]] · [[PORTAL_Robotics#Forward kinematics|Forward kinematics]] · [[PORTAL_Robotics#Degrees of freedom and mobility|Degrees of freedom]] ### Cams and followers *Main article: [[Cam_(mechanism)]] · See also: [[Camshaft]], [[Cam_follower]]* A cam's profile is nothing but a rise–dwell–fall motion law drawn as a radius that varies with angle; choose a harmonic, cycloidal or 3-4-5 polynomial law and the follower's displacement, velocity, acceleration and jerk all follow from the same curve, differentiated. A rough law (harmonic) leaves the acceleration discontinuous at the ends of the rise, which shows up as noise and wear at speed — the reason the smoother cycloidal and polynomial laws exist at all. <div class="wt-sim" data-src="https://wikitube-3d-microsims.netlify.app/engineering/Cam_(mechanism).html" data-title="Cam (mechanism)"></div> *Try: switch the motion law from harmonic to cycloidal to 3-4-5 polynomial and watch the jerk trace go from discontinuous to smooth; then watch the cam profile itself change shape to produce it.* Connects to: [[#The four-bar linkage|Four-bar linkage]] · [[#The four-stroke engine|Four-stroke engine]] · [[PORTAL_Robotics#Grippers and end effectors|Grippers and end effectors]] ### Belts, chains and the capstan *Main article: [[Belt_(mechanical)]] · See also: [[Belt_friction]], [[Capstan_equation]], [[Roller_chain]]* A belt drive sets its speed ratio from the two pulley diameters, same as a gear pair, but it can only transmit as much tension difference as friction and wrap angle allow: the capstan equation T1/T2 = e^(μθ) is the same law whether the belt is wrapped on a pulley or a rope on a bollard, and past that ratio the belt slips rather than pulling harder. A roller chain sidesteps the slip limit entirely by meshing positively with sprocket teeth, at the cost of a small speed ripple (chordal action) once per tooth. <div class="wt-sim" data-src="https://wikitube-3d-microsims.netlify.app/engineering/Belt_(mechanical).html" data-title="Belt (mechanical)"></div> *Try: raise the load until the belt tension ratio hits e^(μθ) and watch it slip; then widen the wrap angle and read how much more tension difference the same friction coefficient can now hold.* Connects to: [[#Simple machines and mechanical advantage|Simple machines]] · [[#Gears and gear trains|Gears]] · [[#Friction, bearings and lubrication|Friction]] ### Flywheels and inertia *Main article: [[Flywheel]] · See also: [[Moment_of_inertia]], [[Rigid_body]]* An engine's torque doesn't arrive smoothly — it pulses once per power stroke — and a flywheel's job is to store the excess energy from the pulse and give it back during the trough, so the shaft's speed fluctuates by only a small coefficient instead of surging and stalling. Stored energy goes as ½Iω², so doubling the speed quadruples the energy a flywheel can hold; a rim-heavy design concentrates the mass where it does the most good, at the cost of being the first shape to fly apart if it's spun past its burst speed. <div class="wt-sim" data-src="https://wikitube-3d-microsims.netlify.app/engineering/Flywheel.html" data-title="Flywheel"></div> *Try: raise the moment of inertia and watch the coefficient of speed fluctuation shrink; then switch from a disc to a rim-weighted design at equal mass and read the stored energy climb.* Connects to: [[#Hooke's law and the spring|Hooke's law]] · [[#Torsion|Torsion]] · [[#Gears and gear trains|Gears]] · [[#The four-stroke engine|Four-stroke engine]] · [[PORTAL_Robotics#The inverted pendulum|Inverted pendulum]] ## Part III — Motion, vibration and vehicles  *Microsims from the articles this section links:* <div class="wt-simrow"> <div class="wt-sim" data-src="https://editor.p5js.org/sciencenibber/full/TrjZRL5AZ" data-title="Dynamics (mechanics) · p5.js"></div> <div class="wt-sim" data-src="https://editor.p5js.org/sciencenibber/full/wEl75DPti" data-title="Dynamics (mechanics) · p5.js (2)"></div> <div class="wt-sim" data-src="https://wikitube-3d-microsims.netlify.app/Tribology.html" data-title="Tribology"></div> <div class="wt-sim" data-src="https://wikitube-3d-microsims.netlify.app/acoustics/Vibration.html" data-title="Vibration · acoustics"></div> <div class="wt-sim" data-src="https://editor.p5js.org/sciencenibber/full/TFprpY6vu" data-title="Vibration · p5.js"></div> </div>  *Serves the [[Automotive_engineering]], [[Dynamics_(mechanics)]], [[Tribology]], [[Vibration]] and [[Control_engineering]] shells.* Part III is where mechanisms meet the road: the friction that both drives a wheel and wears a bearing, the isolation that keeps a machine's vibration from reaching its mounts, and the suspension and steering geometry that turn a chassis into a vehicle with a personality. ### Friction, bearings and lubrication *Main article: [[Friction]] · See also: [[Stick–slip_phenomenon]], [[Bearing_(mechanical)]], [[Rolling-element_bearing]], [[Plain_bearing]], [[Lubrication]], [[Wear]]* A block on a tilting incline sits still until the incline angle reaches tan θ = μs, the static friction limit; past that it slides at a = g(sin θ − μk cos θ), and because the kinetic coefficient is usually lower than the static one, a spring-pulled block sticks and slips rather than sliding smoothly. A bearing's whole purpose is managing that same friction under load — a rolling-element bearing trades sliding for rolling and has a statistical life (ISO 281's L10) rather than a hard limit, while a plain bearing rides a full-film of lubricant whose friction, once the film forms, follows the Stribeck curve down and then back up as speed changes. <div class="wt-sim" data-src="https://wikitube-3d-microsims.netlify.app/engineering/Friction.html" data-title="Friction"></div> *Try: tilt the incline past tan⁻¹(μs) and watch the block break loose; then switch to the spring-pulled block and watch it stick and slip instead of sliding smoothly.* Connects to: [[#Fatigue and fracture|Fatigue and fracture]] · [[#Belts, chains and the capstan|Belts and chains]] · [[#Vehicle suspension|Vehicle suspension]] · [[#Steering geometry and handling|Steering geometry]] · [[PORTAL_Robotics#Haptics and teleoperation|Haptics]] ### Vibration isolation *Main article: [[Vibration_isolation]] · See also: [[Rotordynamics]], [[Critical_speed]]* Mount a vibrating machine on springs soft enough and the transmissibility — the fraction of its shake that reaches the floor — drops below one once the frequency ratio r passes √2; below that line, softer mounts actually make things worse. Damping is a double-edged tool here: it tames the resonance peak at r = 1 but, past the √2 crossover, it works against the mount by transmitting more, not less. A spinning shaft carries the same physics under a different name — a Jeffcott rotor whirls in a growing circle as its speed approaches a critical speed, then, pushed past it, self-centres and quiets back down. <div class="wt-sim" data-src="https://wikitube-3d-microsims.netlify.app/engineering/Vibration_isolation.html" data-title="Vibration isolation"></div> *Try: push the frequency ratio past √2 and watch transmissibility fall into the isolation band; then raise the damping ratio and see it help at resonance but hurt in the isolation region.* Connects to: [[#Hooke's law and the spring|Hooke's law]] · [[#Flywheels and inertia|Flywheels]] · [[#Vehicle suspension|Vehicle suspension]] · [[PORTAL_Robotics#Manipulator dynamics|Manipulator dynamics]] ### Vehicle suspension *Main article: [[Car_suspension]] · See also: [[Sprung_mass]], [[Unsprung_mass]], [[Weight_transfer]], [[Independent_suspension]]* The quarter-car model boils a corner of a vehicle down to two masses — the sprung body and the unsprung wheel — joined by a spring and damper above the wheel and a tire spring below it, and that pair of masses carries two natural frequencies: a slow body bounce and a fast wheel hop. Drive it over a bump or a sine-swept road and both show up in the body's acceleration trace; under braking or cornering, weight transfers longitudinally or laterally (ΔW = mah/L) between the axles or sides, changing how much grip each tire has left to give. <div class="wt-sim" data-src="https://wikitube-3d-microsims.netlify.app/engineering/Car_suspension.html" data-title="Car suspension"></div> *Try: drive the quarter-car over the bump and the sine road and read the body-bounce and wheel-hop frequencies apart; then raise braking deceleration and watch the weight-transfer bar grow.* Connects to: [[#Friction, bearings and lubrication|Friction]] · [[#Vibration isolation|Vibration isolation]] · [[#Steering geometry and handling|Steering geometry]] ### Steering geometry and handling *Main article: [[Ackermann_steering_geometry]] · See also: [[Understeer_and_oversteer]], [[Automobile_handling]], [[Toe_(automotive)]]* A car's two front wheels can't both point at the same turn centre unless the inner wheel steers more sharply than the outer one — Ackermann geometry gets both angles right from the wheelbase and track alone. At speed the simpler bicycle model takes over: a steer angle produces a lateral acceleration whose relationship to that angle is set by an understeer gradient K, positive for a car that needs more steer as speed rises (safer) and negative for one that needs less (twitchier, and eventually unstable). <div class="wt-sim" data-src="https://wikitube-3d-microsims.netlify.app/engineering/Ackermann_steering_geometry.html" data-title="Ackermann steering geometry"></div> *Try: tighten the turn and watch the inner and outer wheel angles diverge from the Ackermann geometry; then flip the understeer gradient's sign and watch the bicycle model's steer-vs-lateral-acceleration line change direction.* Connects to: [[#Friction, bearings and lubrication|Friction]] · [[#Vehicle suspension|Vehicle suspension]] · [[PORTAL_Robotics#Omnidirectional wheels|Omnidirectional wheels]] · [[PORTAL_Robotics#Self-driving cars|Self-driving cars]] ## Part IV — Heat and flow at work *Serves the [[Thermal_engineering]], [[Energy_engineering]], [[Chemical_engineering]], [[Hydraulic_engineering]] and [[Power_engineering]] shells.* Part IV turns heat and fluid into work: the Carnot limit every real cycle sits under, the four-stroke engine and the refrigerator that is the same cycle run in reverse, the heat transfer that sizes every wall and fin, and the pumps, turbines and hydraulic circuits that move fluid and power with it. ### Heat engines and the Carnot limit *Main article: [[Heat_engine]] · See also: [[Carnot_cycle]], [[Thermal_efficiency]]* No cycle operating between a hot reservoir at TH and a cold one at TC can beat the Carnot efficiency, 1 − TC/TH — a ceiling set by the two temperatures alone, with no dependence on what the working fluid is or how the cycle is built. This section has no dedicated Engineering sim of its own; it embeds the live Matter & Energy set's Carnot sim directly, and its two See-also variants (the p–V/T–s cycle, and efficiency plotted against the temperature ratio) are built into the `/engineering/` set with this portal as their home so they read naturally alongside Part IV's other sections. <div class="wt-sim" data-src="https://wikitube-3d-microsims.netlify.app/matter/Heat_engine.html" data-title="Heat engine"></div> *Try: separate TH and TC further and watch the Carnot ceiling rise; then compare it against a real cycle's efficiency on the same axes.* Connects to: [[#The four-stroke engine|Four-stroke engine]] · [[#Refrigeration and heat pumps|Refrigeration]] · [[#Heat transfer|Heat transfer]] · [[#Turbines|Turbines]] ### The four-stroke engine *Main article: — stub, article not yet written (W4) · See also: [[Otto_cycle]], [[Compression_ratio]], [[Diesel_cycle]], [[Diesel_engine]]* > **Stub.** *Four-stroke engine* has no Wikitube article yet; this placeholder stands in until the child-article > pass writes it. A four-stroke engine's piston, driven by the slider-crank mechanism of [[#The four-bar linkage|Part II]], > traces an Otto-cycle p–V diagram once per two crankshaft revolutions — intake, compression, power, exhaust — and > its ideal efficiency, η = 1 − r^(1−γ), rises with the compression ratio alone. A diesel engine runs the same > four strokes but compresses air alone to ignition temperature and injects fuel at nearly constant pressure, > trading the Otto cycle's constant-volume heat addition for the Diesel cycle's constant-pressure one, at a > different point on the same p–V axes. <div class="wt-sim" data-src="https://wikitube-3d-microsims.netlify.app/engineering/Four-stroke_engine.html" data-title="Four-stroke engine"></div> *Try: raise the compression ratio and watch the Otto efficiency climb toward 1 − r^(1−γ); switch to the Diesel cycle and compare where its heat addition happens on the p–V diagram.* Connects to: [[#The four-bar linkage|Four-bar linkage]] · [[#Cams and followers|Cams]] · [[#Flywheels and inertia|Flywheels]] · [[#Heat engines and the Carnot limit|Heat engines]] ### Refrigeration and heat pumps *Main article: [[Refrigeration]] · See also: [[Vapor-compression_refrigeration]], [[Heat_pump]], [[Coefficient_of_performance]]. Link only: [[Heating,_ventilation,_and_air_conditioning]]* Run a heat engine's cycle backward — compress a refrigerant, condense it hot, expand it cold, evaporate it back to a gas — and it pumps heat rather than producing work, at a coefficient of performance the compressor's electrical input buys many times over. Plotted on the refrigerant's own p–h saturation dome, the evaporator and condenser temperatures set the whole cycle's COP; run the same cycle as a heat pump rather than a refrigerator and its COP is exactly one more than the refrigeration COP, because the compressor's own work also ends up as delivered heat. <div class="wt-sim" data-src="https://wikitube-3d-microsims.netlify.app/engineering/Refrigeration.html" data-title="Refrigeration"></div> *Try: narrow the gap between evaporator and condenser temperature and watch COP climb toward the Carnot COP beside it; switch from refrigerator to heat-pump mode and read COP jump by exactly one.* Connects to: [[#Heat engines and the Carnot limit|Heat engines]] · [[#Heat transfer|Heat transfer]] · [[#Pumps|Pumps]] ### Heat transfer  *Microsims from the articles this section links:* <div class="wt-simrow"> <div class="wt-sim" data-src="https://wikitube-3d-microsims.netlify.app/matter/Heat_transfer.html" data-title="Heat transfer · matter"></div> <div class="wt-sim" data-src="https://editor.p5js.org/sciencenibber/full/QRea-7JU3" data-title="Heat transfer · p5.js"></div> </div>  *Main article: [[Heat_transfer]] · See also: [[Heat_exchanger]], [[Heat_sink]], [[Fin_(extended_surface)]]* A composite wall between two fluids resists heat the way a set of resistors in series resists current: conduction through each layer, convection films on either face and, where it matters, radiation, all combine into one thermal resistance that sets the temperature profile straight through the wall. A heat exchanger is that same resistance network turned into hardware, rated by an effectiveness against the maximum heat two streams could possibly exchange; a finned heat sink instead adds surface area, and a fin's efficiency says how much of that added area actually pulls its weight before its own tip cools too far to help. <div class="wt-sim" data-src="https://wikitube-3d-microsims.netlify.app/engineering/Heat_transfer.html" data-title="Heat transfer"></div> *Try: stack a poor insulator between two good conductors and watch the temperature profile bend sharply across it; lengthen a fin and watch its efficiency fall as its tip stops being effectively hot.* Connects to: [[#Heat engines and the Carnot limit|Heat engines]] · [[#Refrigeration and heat pumps|Refrigeration]] · [[#Turbines|Turbines]] · [[#Material selection|Material selection]] ### Pumps *Main article: — stub, article not yet written (W4) · See also: [[Centrifugal_pump]], [[Net_positive_suction_head]], [[Euler's_pump_and_turbine_equation]], [[Specific_speed]]* > **Stub.** *Pump* has no Wikitube article yet. A centrifugal pump's performance curve — head falling as flow rises > — is set by its impeller speed through the affinity laws, and where that curve crosses a system curve (a fixed > static head plus a flow-squared friction loss) is the pump's actual operating point: flow, head and shaft power > all read off that one intersection. Push the operating point too far and the suction side's pressure can drop > below the fluid's vapour pressure, cavitating; net positive suction head is the margin against that, and Euler's > pump-and-turbine equation is the velocity-triangle bookkeeping that predicts the head in the first place. <div class="wt-sim" data-src="https://wikitube-3d-microsims.netlify.app/engineering/Pump.html" data-title="Pump"></div> *Try: raise the system's static head and watch the operating point slide down the pump curve; then push flow up until the NPSH margin runs out and cavitation is called.* Connects to: [[#Refrigeration and heat pumps|Refrigeration]] · [[#Turbines|Turbines]] · [[#Hydraulics and pneumatics|Hydraulics]] ### Turbines  *Microsims from the articles this section links:* <div class="wt-simrow"> <div class="wt-sim" data-src="https://wikitube-3d-microsims.netlify.app/Pelton_wheel.html" data-title="Pelton wheel"></div> <div class="wt-sim" data-src="https://wikitube-3d-microsims.netlify.app/Francis_turbine.html" data-title="Francis turbine"></div> <div class="wt-sim" data-src="https://wikitube-3d-microsims.netlify.app/Water_turbine.html" data-title="Water turbine"></div> <div class="wt-sim" data-src="https://wikitube-3d-microsims.netlify.app/matter/Wind_turbine.html" data-title="Wind turbine"></div> </div>  *Main article: — stub, article not yet written (W4) · See also: [[Pelton_wheel]], [[Francis_turbine]], [[Water_turbine]], [[Steam_turbine]], [[Gas-turbine_engine]], [[Wind_turbine]]* > **Stub.** *Turbine* has no Wikitube article yet. Euler's turbine equation, the same velocity-triangle bookkeeping > that predicts a pump's head, predicts a turbine's power in reverse; a Pelton wheel is the cleanest case, an > impulse turbine whose bucket power peaks when the bucket speed u is exactly half the jet velocity V. Reaction > turbines (Francis, and the generality of water turbines) drop pressure across the moving blades rather than > before them, and the same energy-conversion argument extends to steam turbines, to the Brayton-cycle gas turbine, > and — where the fluid is air instead of steam — to a wind turbine, whose Betz limit caps how much of the wind's > kinetic energy any turbine can extract at 16/27. > > [[Pelton_wheel]], [[Francis_turbine]] and [[Water_turbine]] already exist as thin legacy pages and are promoted, > not replacing, once the article pass reaches them. <div class="wt-sim" data-src="https://wikitube-3d-microsims.netlify.app/engineering/Turbine.html" data-title="Turbine"></div> *Try: slide the Pelton bucket speed to u/V = ½ and watch power peak there; switch from impulse to reaction and compare where the pressure actually drops.* Connects to: [[#Heat engines and the Carnot limit|Heat engines]] · [[#Pumps|Pumps]] · [[#Hydraulics and pneumatics|Hydraulics]] · [[#Flywheels and inertia|Flywheels]] ### Hydraulics and pneumatics *Main article: — stub, article not yet written (W4) · See also: [[Pascal's_law]], [[Hydraulic_press]], [[Hydraulic_cylinder]], [[Pneumatics]]* > **Stub.** *Hydraulics* has no Wikitube article yet. Pascal's law says a confined fluid transmits pressure equally > in every direction, so a hydraulic press multiplies force by the ratio of its two piston areas while dividing > stroke by the same ratio — the lever from [[#Simple machines and mechanical advantage|Part II]], done with fluid > instead of a beam. A hydraulic cylinder's speed follows directly from pump flow divided by piston area; swap the > incompressible fluid for air and a pneumatic cylinder behaves like a nonlinear spring instead, because the gas > itself compresses under load. `Hydraulic_cylinder`'s own worklist entry belongs to the Robotics spine's ROB6 > (Actuators), which this section only links to. <div class="wt-sim" data-src="https://wikitube-3d-microsims.netlify.app/engineering/Hydraulics.html" data-title="Hydraulics"></div> *Try: change the two piston areas on the press and read force multiply while stroke divides by the same ratio; switch the cylinder from hydraulic to pneumatic and watch it start behaving like a spring.* Connects to: [[#Simple machines and mechanical advantage|Simple machines]] · [[#Pumps|Pumps]] · [[PORTAL_Robotics#Actuators|Actuators]] *Cross-set variants, no section of their own:* [[Nozzle]], [[De_Laval_nozzle]] and [[Choked_flow]] extend the Thury Compendium's `Compressible_flow` sim with this portal as their home (area ratio → Mach number, choking, shock position) — three more built, un-staged sims that belong to Part IV's story without a Main article of their own to anchor a full section. ## Part V — Design and manufacturing  *Microsims from the articles this section links:* <div class="wt-sim" data-src="https://wikitube-3d-microsims.netlify.app/Reliability_engineering.html" data-title="Reliability engineering"></div>  *Serves the [[Manufacturing_engineering]], [[Industrial_engineering]], [[Engineering_drawing]], [[3D_printing]], [[Materials_science]] and [[Reliability_engineering]] shells.* The last part is where a design becomes a real, buildable part: the tolerances that say how loose a fit can be, the finite element method that predicts a shape's stiffness before it's cut, the machining and forming and printing processes that actually make it, and the material chart that closes the loop by saying which material a given shape should be made from. ### Tolerances and fits *Main article: — stub, article not yet written (W4) · See also: [[Interference_fit]], [[Allowance_(engineering)]], [[Tolerance_analysis]]* > **Stub.** *Engineering tolerance* has no Wikitube article yet. A shaft has to go in a hole, and the ISO tolerance > grade assigned to each sets the band each dimension is allowed to wander in; where those two bands land relative > to each other decides whether the result is a clearance fit (it slides), a transition fit (it might), or an > interference fit (it has to be pressed or shrunk in, and the resulting contact pressure follows a Lamé > thick-wall solution). Stack four toleranced parts end to end and the total tolerance either adds up worst-case > (every part at its limit at once) or, more realistically, combines by root-sum-square, since independent errors > rarely all land at their worst simultaneously. <div class="wt-sim" data-src="https://wikitube-3d-microsims.netlify.app/engineering/Engineering_tolerance.html" data-title="Engineering tolerance"></div> *Try: tighten the ISO grade and watch the clearance band narrow toward an interference fit; build a four-part stack and compare its worst-case total against the RSS estimate.* Connects to: [[#Buckling|Buckling]] · [[#Machining and CNC|Machining and CNC]] · [[#Metal forming|Metal forming]] · [[PORTAL_Robotics#Grippers and end effectors|Grippers]] ### The finite element method *Main article: [[Finite_element_method]] · See also: [[Direct_stiffness_method]], [[Stiffness_matrix]]* A tapered bar, or a small truss, can be solved exactly by hand, but the method that scales to a real part starts the same way: break the shape into elements, write each one's stiffness matrix, assemble them into one global matrix K, and solve Ku = F for every node's displacement at once. Refine the mesh — more, smaller elements — and the tip deflection converges on the exact answer from one side, which is the whole justification for trusting a coarse first mesh's trend even before a fine mesh confirms the number. <div class="wt-sim" data-src="https://wikitube-3d-microsims.netlify.app/engineering/Finite_element_method.html" data-title="Finite element method"></div> *Try: refine the mesh from two elements to twelve and watch the tip deflection converge; colour the elements by stress and find where the load concentrates.* Connects to: [[#Bending of beams|Bending]] · [[#Buckling|Buckling]] · [[#Material selection|Material selection]] ### Machining and CNC *Main article: — stub, article not yet written (W4) · See also: [[Machining]], [[G-code]], [[Computer-aided_manufacturing]]* > **Stub.** *Computer numerical control* has no Wikitube article yet. A cutting tool's spindle speed comes from the > material's recommended cutting speed and the tool diameter (RPM = CS·4/D), and the feed rate follows from RPM, > the number of teeth and the feed per tooth — two numbers a machinist once read off a shop table and a CNC > controller now computes automatically. G-code turns a toolpath into that same automation: G01 for a straight cut, > G02/G03 for an arc, each line moving the tool exactly as far and as fast as the program says. <div class="wt-sim" data-src="https://wikitube-3d-microsims.netlify.app/engineering/Computer_numerical_control.html" data-title="Computer numerical control"></div> *Try: change the tool diameter and material and watch the recommended spindle speed update; then step a G02 arc move and watch the tool follow it.* Connects to: [[#Tolerances and fits|Tolerances and fits]] · [[#Metal forming|Metal forming]] · [[#Design for additive manufacturing|Additive manufacturing]] · [[PORTAL_Robotics#Localization and mapping|Localization and mapping]] ### Metal forming *Main article: — stub, article not yet written (W4) · See also: [[Forging]], [[Extrusion]], [[Sheet_metal]]* > **Stub.** *Rolling (metalworking)* has no Wikitube article yet. Flat rolling squeezes a slab between two rolls > whose radius and the slab's draft set a contact angle; rolling only "bites" and pulls the slab in on its own when > friction is high enough that μ ≥ tan(contact angle), below which the rolls simply spin against the surface. Roll > force follows from that contact area times the material's flow stress — read straight off the stress–strain > curve's hardening law — and the same flow stress governs open-die forging (which barrels as it upsets) and > extrusion, where the pressure needed rises with the log of how much the cross-section is reduced. <div class="wt-sim" data-src="https://wikitube-3d-microsims.netlify.app/engineering/Rolling_(metalworking).html" data-title="Rolling (metalworking)"></div> *Try: raise the draft until the bite condition μ ≥ tan α fails and the rolls stop pulling the slab in; then compare roll force against a forging upset at the same flow stress.* Connects to: [[#The stress–strain curve|Stress–strain curve]] · [[#Machining and CNC|Machining and CNC]] · [[#Design for additive manufacturing|Additive manufacturing]] ### Design for additive manufacturing *Main article: — stub, article not yet written (W4) · See also: [[Design_for_manufacturability]]* > **Stub.** *Fused filament fabrication* has no Wikitube article yet. A 3-D printed part is built one layer at a > time, and the visible "staircase" on an angled surface is pure geometry: cusp height h = t·cos(α) for a layer > thickness t and a surface angle α, which is also why the common 45° rule of thumb marks where a face needs > printed support underneath it rather than printing over open air. Layer height trades that surface quality > against build time directly — thinner layers, smoother parts, longer prints. <div class="wt-sim" data-src="https://wikitube-3d-microsims.netlify.app/engineering/Fused_filament_fabrication.html" data-title="Fused filament fabrication"></div> *Try: tilt the part past 45° and watch the faces needing support light up; then thin the layer height and watch build time climb as the cusp shrinks.* Connects to: [[#Machining and CNC|Machining and CNC]] · [[#Metal forming|Metal forming]] · [[#Material selection|Material selection]] · [[PORTAL_Robotics#Legged locomotion and gaits|Legged locomotion]] ### Material selection *Main article: [[Material_selection]] · See also: [[Specific_strength]], [[Specific_modulus]]* Plot every candidate material's stiffness against its density on log–log axes (an Ashby chart) and a family of parallel lines — one performance index per line, E/ρ for a light stiff tie, E^½/ρ for a light stiff beam, E^⅓/ρ for a light stiff panel — picks out the best material for a given shape of loading, not just the strongest one in absolute terms. Slide the line across the chart and the ranking changes with the exponent, which is the Ashby method's whole point: the right material depends on how the part is loaded, not on a single strength number. <div class="wt-sim" data-src="https://wikitube-3d-microsims.netlify.app/engineering/Material_selection.html" data-title="Material selection"></div> *Try: switch the performance index from E/ρ to E^½/ρ to E^⅓/ρ and watch the ranked material list reorder itself on the same chart.* Connects to: [[#The stress–strain curve|Stress–strain curve]] · [[#Buckling|Buckling]] · [[#Heat transfer|Heat transfer]] · [[#Design for additive manufacturing|Additive manufacturing]] · [[PORTAL_Robotics#Legged locomotion and gaits|Legged locomotion]] ## Crossover with Robotics The two spines were planned together and cross at fourteen points, written into the Connects-to lines above and in [[PORTAL_Robotics]]'s own sections: gears and simple machines feed the [[PORTAL_Robotics#Actuators|actuator]] a robot joint runs on; the four-bar linkage's vector-loop kinematics and mobility count are the same mathematics as [[PORTAL_Robotics#Forward kinematics|forward kinematics]] and [[PORTAL_Robotics#Degrees of freedom and mobility|degrees of freedom]]; a cam's motion law is a [[PORTAL_Robotics#Grippers and end effectors|gripper]]'s motion profile; flywheel inertia is the inertia term in a manipulator's [[PORTAL_Robotics#Manipulator dynamics|equations of motion]]; friction closes a [[PORTAL_Robotics#Grippers and end effectors|grasp]] the same way it holds a block on an incline; vibration isolation is a servo's structural-resonance limit; the bicycle model of steering and suspension is exactly the plant a [[PORTAL_Robotics#Self-driving cars|self-driving car]] controls; hydraulics power an actuator directly; tolerances set what a robot can [[PORTAL_Robotics#Industrial robots|repeat]]; a CNC toolpath is a planned path in the same sense [[PORTAL_Robotics#Motion planning|motion planning]] means it; and material selection and additive manufacturing choose what a [[PORTAL_Robotics#Wearable robots|wearable robot]] is built from. `Mechatronics` is the named bridge article both portals point to. ## Book shelf Cited by section number above and in the full plan (`_registry/plans/ENGINEERING_SECTIONS.md`), by Portal Books PDF page: **109** Jensen (mobility, gears, linkages, cams, belts, screws — the mechanism backbone of Parts II–III), **077** (stress, strain, moduli, friction), **009** (buckling, torsion, fatigue — aerospace structures), **115** Yan (heat engines, refrigeration), **105** (pumps, turbines, Pelton), **111** (drawing and tolerancing), **110** (design for additive manufacturing), **094** (machining and cutting speeds), **021** and **073** (vibration and second-order machinery). Standard textbook forms not printed in the shelf (Mohr's circle, Hibbeler-form torsion, Shigley-form belts, Gillespie-form vehicle dynamics, Kalpakjian-form forming, Logan-form FEM, ISO 286 and ISO 281) are marked *standard* in the plan rather than cited to a page. ## Workproduct and work list Every section below already has its microsim built and bench-passing (**29 of 29** possible roots — Part IV's Section 18 has none by design, see below). What is still catching up is the *article* layer: this run minted 16 new Main articles in its first wave and the vault already carried 6 dense mechanical-engineering pages that only needed a sim dropped in, for **22 of 30 Main articles written**. The other **8 are stubs** — short placeholders below, standing in until the child-article pass (W4) writes them properly. Of the roughly 99 See-also variants the plan calls for, 97 are built; the remaining two are deliberate link-only cross-references to other portals, not gaps. Deploy state, as of this page's writing (2026-09-19): the first 18 roots plus their variants — **62 sims** — are staged *and live* on `wikitube-3d-microsims.netlify.app/engineering/`. The other 11 roots and their variants — 66 more sims, finished and gated the same day — are built in the framework's `site/engineering/` folder but not yet copied to the deploy stage; running `deploy_engineering_set.sh` again is what makes them playable. The table below marks every section **live**, **staged** (copied to the deploy folder, playable once the next `deploy_engineering_set.sh` run goes out — currently everything staged already **is** live) or **built** (finished, gated, waiting to be staged). | # | Section | Main article | Sim | Variants (built) | |---|---|---|---|---| | ENG1 | Stress and strain | [[Stress_(mechanics)]] | **live** | 2/2 live | | ENG2 | Hooke's law and the spring | [[Hooke's_law]] | **live** | 3/3 live | | ENG3 | The stress–strain curve | [[Stress–strain_curve]] | **live** | 4/4 live | | ENG4 | Bending of beams | [[Bending]] | **live** | 4/4 built | | ENG5 | Buckling | [[Buckling]] | **live** | 2/2 live | | ENG6 | Torsion | [[Torsion_(mechanics)]] | **live** | 2/2 live | | ENG7 | Fatigue and fracture | [[Fatigue_(material)]] | **live** | 2/2 live | | ENG8 | Simple machines | [[Simple_machine]] | **live** | 7/7 live | | ENG9 | Gears and gear trains | [[Gear]] | **live** | 5/5 built | | ENG10 | The four-bar linkage | [[Four-bar_linkage]] | **live** | 3/3 built | | ENG11 | Cams and followers | [[Cam_(mechanism)]] | **live** | 2/2 live | | ENG12 | Belts, chains, the capstan | [[Belt_(mechanical)]] | **live** | 3/3 live | | ENG13 | Flywheels and inertia | [[Flywheel]] | **live** | 2/2 live | | ENG14 | Friction, bearings, lubrication | [[Friction]] | **live** | 6/6 live | | ENG15 | Vibration isolation | [[Vibration_isolation]] | **live** | 2/2 live | | ENG16 | Vehicle suspension | [[Car_suspension]] | **live** | 4/4 live | | ENG17 | Steering geometry and handling | [[Ackermann_steering_geometry]] | **live** | 3/3 live | | ENG18 | Heat engines and the Carnot limit | [[Heat_engine]] | **live** (`/matter/`, no dedicated root) | 2/2 built | | ENG19 | The four-stroke engine | **stub** | **built** | 4/4 built | | ENG20 | Refrigeration and heat pumps | [[Refrigeration]] | **live** | 3/3 built, 1 link-only | | ENG21 | Heat transfer | [[Heat_transfer]] | **built** | 3/3 built | | ENG22 | Pumps | **stub** | **built** | 4/4 built | | ENG23 | Turbines | **stub** | **built** | 6/6 built | | ENG24 | Hydraulics and pneumatics | **stub** | **built** | 4/4 built | | ENG25 | Tolerances and fits | **stub** | **built** | 3/3 built | | ENG26 | The finite element method | [[Finite_element_method]] | **built** | 2/2 built | | ENG27 | Machining and CNC | **stub** | **built** | 3/3 built | | ENG28 | Metal forming | **stub** | **built** | 3/3 built | | ENG29 | Design for additive manufacturing | **stub** | **built** | 1/1 built | | ENG30 | Material selection | [[Material_selection]] | **built** | 2/2 built | **Totals:** 30 sections · 29 section sims (ENG18 has none by design) + 3 cross-set nozzle variants · ~97 See-also variants built · 22 Main articles written, 8 stubbed below · 62 sims live, 66 built and awaiting a deploy pass. The full roadmap — child articles, the g29 generator, media, the deploy handoff MTN still has to run — is `_registry/plans/ENGINEERING_ROBOTICS_HANDOFF.md`; a same-day publish checklist is `_registry/plans/PUBLISH_NOW_2026-09-19.md`. ## Work list — what is left 1. **W4 — child articles.** Eight stub sections above (Four-stroke engine, Pumps, Turbines, Hydraulics, Tolerances and fits, Machining and CNC, Metal forming, Additive manufacturing) need Main articles at wt-article density; `Pelton_wheel`, `Francis_turbine` and `Water_turbine` need append-only promotion from their existing thin pages. The six dense pre-existing articles (Stress–strain curve, Fatigue, Heat transfer, FEM, Material selection, and Heat_engine itself) only need their generator-block sim embed, no rewrite. 2. **Flagship draft.** `_registry/plans/drafts/WT!Engineering_Compendium.draft.md` — thirty sections of flagship prose around these same sims, for MTN to place as a `WT!` page (automations do not write `WT!` pages). 3. **W5 — generator and registry.** `_tools/generate/g29_engineering_sims.py` places `` marker blocks in each article and writes the pending registry rows; it has not run yet for the 11 sections built after wave 1. 4. **W6/W7 — media and the remaining deploy.** The 66 built-but-unstaged sims (Sections 19, 21–30 and their variants) need `deploy_engineering_set.sh` run again to reach `_3d_deploy_stage/` and go live; thumbnails and two short films exist for wave 1 only. The full detail, including every agent report and every library fix along the way, is in `_registry/plans/ENGINEERING_ROBOTICS_HANDOFF.md`. --- *Created 2026-09-19 (wt-portal §6 pass) · sourced from `_registry/plans/ENGINEERING_SECTIONS.md`, the 2026-09-19 build ledger (`engrun_status_2026-09-18.tsv`, `_3d_deploy_stage/engineering/`) and `PUBLISH_NOW_2026-09-19.md` · sibling: [[PORTAL_Robotics]] · index: [[PORTAL_INDEX]]* --- *Repopulated 2026-09-19 · append-only · source: _tools/generate/g34_portal_section_sims.py@00a28cb2 (players of the linked articles, each URL 200-checked) · 68 added · 0 deletions*  ## In service of Space Mining in Minnesota · added 2026-09-22 > **Permissions to request up front (house rule, MTN 2026-09-22).** Any agent that works this page — its spine, the worklists at its foot, or its shard — states before its first tool call every permission the run will need and asks for all of them in one round: (1) browser-pane site access, scope *site*: en.wikipedia.org (title and oldid verification), wikitube-3d-microsims.netlify.app (200-checks of players), cdn.jsdelivr.net (library pins), and gutenberg.org / archive.org / ntrs.nasa.gov only if a book is re-fetched; (2) folder access to the vault root (`en.wikitube.io/`) and, for a deploy pass, to `_3d_deploy_stage/`; (3) no `WT!` authorization is needed for this page — it is an ordinary portal — but touching `WT!Space_Mining_In_Minnesota` or its `PORTAL_WT!` page needs MTN's (WIKI_RULES §1, §11); (4) no delete permission — everything here is append-only; (5) production deploy is MTN's: the run stages into `_3d_deploy_stage/<set>/` and hands over the deploy script. Nothing else. **Engineering in service of the apex.** The cutting wedge, machines and tolerances, radiators and thermal design, the mass driver's coils — the mechanical engineering under every digger, mill, cell and printer on the spine. This second spine sits beside the page's own: thirty sections chosen for what they supply to [[WT!Space_Mining_In_Minnesota]], one three.js microsim per section, and a hero — **The Watt Line**, an instance of the Master Portal Hero — with the two worklists at the foot. Apex: [[PORTAL_WT!Space_Mining_In_Minnesota]] · hub: [[PORTAL_Centers_of_Excellence]]. Files of this spine: plan `_registry/plans/ENGINEERING_IN_SERVICE_SECTIONS.md` (beside the page's own `ENGINEERING_SECTIONS.md`), shard `Style Guide and Worklist/PORTAL_Engineering.worklist.md`, record `Style Guide and Worklist/worklists/PORTAL_Engineering/jobs.json`, pack `specs/portals/PORTAL_Engineering.pack.json`, set `engineering/`.  <div class="wt-sim" data-src="https://wikitube-3d-microsims.netlify.app/engineering/Watt_Line.html" data-title="The Watt Line"></div>  *The Watt Line (ENG-HERO, `engineering/Watt_Line.html`, built and gated SHIP 2026-09-22, 36 URL states walked headless with an empty console; the player goes live with MTN's next production publish): the power at a machine's terminals walked through motor, gearbox, bearings, drivetrain, tool, work, heat on five machines. Every section below is a stage or a component of it, and a child article embeds the hero locked on its own state (`?body=<id>&stage=<id>&embed=1`) until its section sim ships.* ### Spine (in service) | # | Article | Reveal | Microsim | Node | |---|---|---|---|---| | ⊙ | [[PORTAL_Engineering]] | three | `engineering/Watt_Line.html` — The Watt Line, 36 URL states (`?body=&stage=&embed=1`); **built, SHIP** 2026-09-22, awaiting publish | ENG-HERO | | | **Part I — Loads and materials** | | | | | 1 | [[Stress_(mechanics)]] | three | `engineering/Stress_(mechanics).html` — this portal's existing player (re-verify, then add the in-service preset) | ENG-001 | | 2 | [[Hooke's_law]] | three | `engineering/Hooke's_law.html` — this portal's existing player (re-verify, then add the in-service preset) | ENG-002 | | 3 | [[Compressive_strength]] | three | `engineering/Compressive_strength.html` — queued (row ENG-003) — supersedes the apex's variant SMM-181 | ENG-003 | | 4 | [[Fatigue_(material)]] | three | `matter/Fatigue_(material).html` — this portal's existing player (re-verify, then add the in-service preset) | ENG-004 | | 5 | [[Beam_(structure)]] | three | `engineering/Beam_(structure).html` — queued (row ENG-005) | ENG-005 | | | **Part II — Machines and mechanisms** | | | | | 6 | [[Machine]] | three | `engineering/Machine.html` — queued (row ENG-006) | ENG-006 | | 7 | [[Gear]] | three | `engineering/Gear.html` — this portal's existing player (re-verify, then add the in-service preset) | ENG-007 | | 8 | [[Bearing_(mechanical)]] | three | `engineering/Bearing_(mechanical).html` — queued (row ENG-008) | ENG-008 | | 9 | [[Excavator]] | three | `engineering/Excavator.html` — queued (row ENG-009) | ENG-009 | | 10 | [[Conveyor_belt]] | three | `engineering/Conveyor_belt.html` — queued (row ENG-010) | ENG-010 | | | **Part III — Drives and power** | | | | | 11 | [[Electric_motor]] | three | `engineering/Electric_motor.html` — queued (row ENG-011) | ENG-011 | | 12 | [[Linear_motor]] | three | `engineering/Linear_motor.html` — queued (row ENG-012) | ENG-012 | | 13 | [[Solenoid]] | three | `engineering/Solenoid.html` — queued (row ENG-013) | ENG-013 | | 14 | [[Electric_battery]] | three | `engineering/Electric_battery.html` — queued (row ENG-014) | ENG-014 | | 15 | [[Hydraulics]] | three | `engineering/Hydraulics.html` — this portal's existing player (re-verify, then add the in-service preset) | ENG-015 | | | **Part IV — Heat and thermal design** | | | | | 16 | [[Radiator]] | three | `engineering/Radiator.html` — queued (row ENG-016) | ENG-016 | | 17 | [[Thermal_insulation]] | three | `engineering/Thermal_insulation.html` — queued (row ENG-017) | ENG-017 | | 18 | [[Heat_exchanger]] | three | `engineering/Heat_exchanger.html` — queued (row ENG-018) | ENG-018 | | 19 | [[Solar_furnace]] | three | `engineering/Solar_furnace.html` — queued (row ENG-019) — supersedes the apex's variant SMM-226 | ENG-019 | | 20 | [[Thermal_expansion]] | three | `engineering/Thermal_expansion.html` — queued (row ENG-020) | ENG-020 | | | **Part V — Precision, tolerance and control** | | | | | 21 | [[Engineering_tolerance]] | three | `engineering/Engineering_tolerance.html` — this portal's existing player (re-verify, then add the in-service preset) | ENG-021 | | 22 | [[Metrology]] | three | `engineering/Metrology.html` — queued (row ENG-022) — supersedes the apex's variant SMM-236 | ENG-022 | | 23 | [[Control_system]] | three | `engineering/Control_system.html` — queued (row ENG-023) | ENG-023 | | 24 | [[Finite_element_method]] | three | `engineering/Finite_element_method.html` — this portal's existing player (re-verify, then add the in-service preset) | ENG-024 | | 25 | [[Reliability_engineering]] | three | `Reliability_engineering.html` — this portal's existing player (re-verify, then add the in-service preset) | ENG-025 | | | **Part VI — Systems and the engineers on the shelf** | | | | | 26 | [[Systems_engineering]] | three | `engineering/Systems_engineering.html` — queued (row ENG-026) | ENG-026 | | 27 | [[Robotics]] | three | `engineering/Robotics.html` — queued (row ENG-027) | ENG-027 | | 28 | [[Mining_engineering]] | three | `engineering/Mining_engineering.html` — queued (row ENG-028) — supersedes the apex's variant SMM-161 | ENG-028 | | 29 | [[W._J._M._Rankine]] | three | `engineering/W._J._M._Rankine.html` — queued (row ENG-029) | ENG-029 | | 30 | [[Vitruvius]] | three | `engineering/Vitruvius.html` — queued (row ENG-030) | ENG-030 | ### The six parts (skeletal outline) #### Part I — Loads and materials 1. **Stress** — *Main article: [[Stress_(mechanics)]] · See also: [[Strain_(mechanics)]], [[Shear_stress]], [[Mohr's_circle]], [[Yield_(engineering)]].* A blade tip in rock: the normal and shear stress on a cut face, Mohr's circle turning to the worst plane — `sigma = F / A` (a ratio). Serves apex sections 15. 2. **Hooke's law** — *Main article: [[Hooke's_law]] · See also: [[Young's_modulus]], [[Spring_(device)]], [[Stiffness]].* A spring, a bar, a tether: force proportional to stretch until it is not — `F = k x` (a linear law). Serves apex sections 10, 24. 3. **Compressive strength** — *Main article: [[Compressive_strength]] · See also: [[Ultimate_tensile_strength]], [[Brittleness]], [[Rock_mass_rating]].* UCS 100 MPa rock against 250 MPa taconite against a sintered regolith brick: the strength that sets the cutting force — `sigma_c = F_max / A` (a threshold). Serves apex sections 15, 22. 4. **Fatigue** — *Main article: [[Fatigue_(material)]] · See also: [[Fracture_mechanics]].* A bucket tooth cycled a million times: the S-N curve and the crack that grows a little every dig — `N_f = f(sigma_a)` (a power law in cycles). Serves apex sections 15, 24. 5. **Beam** — *Main article: [[Beam_(structure)]] · See also: [[Bending]], [[Euler–Bernoulli_beam_theory]], [[Buckling]], [[Deflection_(engineering)]].* The excavator's boom and the radiator's strut: bending stress and deflection, buckling of a slender column at one-sixth g — `M = E I d2y/dx2` (a second-order ODE). Serves apex sections 15, 27. #### Part II — Machines and mechanisms 6. **Machine** — *Main article: [[Machine]] · See also: [[Simple_machine]], [[Mechanical_advantage]], [[Mechanism_(engineering)]].* Lever, wheel, screw: the six simple machines and the advantage each buys, the excavator as a chain of them — `MA = F_out / F_in` (a ratio). Serves apex sections 15. 7. **Gear** — *Main article: [[Gear]] · See also: [[Gear_train]], [[Involute_gear]], [[Torque]].* The mill's drive: ratio, torque and speed trading places through a gear train; efficiency per mesh — `T2/T1 = N2/N1` (a ratio). Serves apex sections 16, 24. 8. **Bearing** — *Main article: [[Bearing_(mechanical)]] · See also: [[Rolling-element_bearing]], [[Plain_bearing]], [[Lubrication]], [[Tribology]].* Friction in a rolling bearing and a plain bearing in vacuum: no oil film, dry lubricants, the heat that has nowhere to go — `T_f = mu F r` (a proportionality). Serves apex sections 24. 9. **Excavator** — *Main article: [[Excavator]] · See also: [[Bucket-wheel_excavator]], [[Dragline_excavator]], [[Loader_(equipment)]].* The digger's cycle: dig, swing, dump, return — the bucket force from the Delft model, the cycle time from the drives — `F_h = f(alpha, phi, h_i, g)` (a 2x2 equilibrium). Serves apex sections 11, 15. 10. **Conveyor belt** — *Main article: [[Conveyor_belt]] · See also: [[Bulk_material_handling]], [[Screw_conveyor]], [[Bucket_elevator]].* Tonnes per hour from belt speed, width and burden; the lunar case with a sixth of the weight to hold the rock down — `Q = rho A v` (a product). Serves apex sections 11, 16. #### Part III — Drives and power 11. **Electric motor** — *Main article: [[Electric_motor]] · See also: [[Brushless_DC_electric_motor]], [[Efficiency]].* Torque and speed from voltage and current: the motor curve, the efficiency map, the mill's 5 MW — `P = T omega` (a product). Serves apex sections 16, 24. 12. **Linear motor** — *Main article: [[Linear_motor]] · See also: [[Coilgun]], [[Railgun]], [[Maglev]].* The mass driver as a linear motor: coil by coil, the bucket accelerates; exit speed from track length and acceleration — `v = sqrt(2 a L)` (kinematics). Serves apex sections 10. 13. **Solenoid** — *Main article: [[Solenoid]] · See also: [[Inductor]], [[Inductance]], [[Magnetic_flux]].* The field inside a coil and the energy it stores: the capacitor bank's joules per shot — `B = mu0 n I` (a proportionality). Serves apex sections 10. 14. **Battery** — *Main article: [[Electric_battery]] · See also: [[Lithium-ion_battery]], [[Energy_density]], [[Specific_energy]].* The lunar night, 354 hours long: kilowatt-hours per kilogram against the night's demand; when fission beats batteries — `E = sum P dt` (an integral). Serves apex sections 26. 15. **Hydraulics** — *Main article: [[Hydraulics]] · See also: [[Hydraulic_cylinder]], [[Pascal's_law]], [[Hydraulic_machinery]].* Pascal's law in the excavator's arm: pressure times area, the cylinder's force, the fluid that freezes at the pole — `F = p A` (a product). Serves apex sections 15. #### Part IV — Heat and thermal design 16. **Radiator** — *Main article: [[Radiator]] · See also: [[Spacecraft_thermal_control]], [[Heat_pipe]], [[Radiator_(engine_cooling)]].* The radiator equation with a fin: area against temperature, the mass per kilowatt rejected — `A = Q / (eps sigma (T^4 - T_sink^4))` (a fourth-power law). Serves apex sections 27. 17. **Thermal insulation** — *Main article: [[Thermal_insulation]] · See also: [[Multi-layer_insulation]], [[Thermal_conductivity_and_resistivity]], [[R-value_(insulation)]].* Multi-layer insulation on a cold trap's reactor: layers against heat leak, regolith itself as insulation — `q = dT / R` (a gradient law). Serves apex sections 20, 27. 18. **Heat exchanger** — *Main article: [[Heat_exchanger]] · See also: [[Countercurrent_exchange]], [[Logarithmic_mean_temperature_difference]], [[Heat_recovery_ventilation]].* Recover the reactor's heat: counterflow, the log-mean temperature difference, the energy saved per kilogram — `Q = U A dT_lm` (a product). Serves apex sections 20. 19. **Furnace** — *Main article: [[Solar_furnace]] · See also: [[Induction_heating]], [[Electric_arc_furnace]], [[Kiln]].* The pellet plant's induration furnace and a solar furnace on the Moon: 1,300 C by fuel, by arc, by mirror — `Q = m c dT + m L` (an energy balance). Serves apex sections 22. 20. **Thermal expansion** — *Main article: [[Thermal_expansion]] · See also: [[Thermal_stress]], [[Bimetallic_strip]].* A machine that sees 390 K by day and 100 K by night: expansion, thermal stress, the fit that binds — `dL = alpha L dT` (a linear law). Serves apex sections 24, 27. #### Part V — Precision, tolerance and control 21. **Engineering tolerance** — *Main article: [[Engineering_tolerance]] · See also: [[Tolerance_analysis]], [[Interchangeable_parts]], [[Engineering_fit]], [[Geometric_dimensioning_and_tolerancing]].* Ten parts in a stack: the root-sum-square against the worst case; the fit that a machinist a million kilometres away cannot adjust — `t_stack = sqrt(sum t_i^2)` (a root-sum-square). Serves apex sections 24. 22. **Metrology** — *Main article: [[Metrology]] · See also: [[Coordinate-measuring_machine]], [[Calibration]], [[Gauge_block]], [[Measurement_uncertainty]].* Measuring the part you made: the CMM, the gauge, the uncertainty budget — `u_c = sqrt(sum u_i^2)` (an uncertainty budget). Serves apex sections 24. 23. **Control system** — *Main article: [[Control_system]] · See also: [[Control_theory]], [[PID_controller]], [[Feedback]], [[Servomechanism]].* A furnace at 1,300 C and a lathe on a curve: the PID loop, its gains, its overshoot — `u = Kp e + Ki int e + Kd de/dt` (a feedback law). Serves apex sections 22, 24. 24. **Finite element method** — *Main article: [[Finite_element_method]] · See also: [[Mesh_generation]], [[Structural_analysis]], [[Computational_mechanics]].* The boom meshed and loaded: stress in every element, the picture the hand calculation approximates — `K u = f` (a linear system). Serves apex sections 15, 27. 25. **Reliability engineering** — *Main article: [[Reliability_engineering]] · See also: [[Failure_rate]], [[Mean_time_between_failures]], [[Redundancy_(engineering)]].* A machine with no repair shop: MTBF, the bathtub curve, the spare-part mass the printer replaces — `R(t) = exp(-lambda t)` (an exponential). Serves apex sections 21, 25. #### Part VI — Systems and the engineers on the shelf 26. **Systems engineering** — *Main article: [[Systems_engineering]] · See also: [[Requirement]], [[Verification_and_validation]], [[Trade_study]].* The ISRU plant as a system: requirements, interfaces, the trade between launch mass and complexity — `mass, power, cost, risk` (a trade table). Serves apex sections 1, 29. 27. **Robotics** — *Main article: [[Robotics]] · See also: [[Industrial_robot]], [[Autonomous_robot]], [[Teleoperation]], [[Robot_kinematics]].* A digger that nobody drives: light-time delay, autonomy, the arm's kinematics — `x = f(theta)` (forward kinematics). Serves apex sections 11, 25. 28. **Mining engineering** — *Main article: [[Mining_engineering]] · See also: [[Mining]], [[Rock_mechanics]], [[Mineral_processing]].* The discipline that owns the pit: Hoover's and Peele's engineering, applied where there is no air — `cost per ton` (a linear cost model). Serves apex sections 11. 29. **William John Macquorn Rankine** — *Main article: [[W._J._M._Rankine]] · See also: [[Rankine's_theory]], [[Lateral_earth_pressure]], [[Rankine_cycle]].* The Manual of Applied Mechanics: friction, earth pressure, the heap at its friction angle — Rankine's articles behind the regolith sim — `K_p = (1 + sin phi)/(1 - sin phi)` (a trigonometric ratio). Serves apex sections 14. 30. **Vitruvius** — *Main article: [[Vitruvius]] · See also: [[De_architectura]], [[Ancient_Roman_engineering]], [[Water_wheel]].* The Ten Books on Architecture: machines for lifting, water and the first engineering handbook on the shelf — `MA = d_in / d_out` (a ratio). Serves apex sections 15. ### Shelf (in service) | Book | Author, year | Licence | Where it serves | |---|---|---|---| | *The Ten Books on Architecture* | Vitruvius (tr. M. H. Morgan), c. 25 BCE (tr. 1914) | PD (Gutenberg) | `books/engineering` | | *A Manual of Applied Mechanics* | W. J. M. Rankine, 1858 (1877 ed.) | PD | `books/engineering` | ### Crosslinks (in service) **Apex:** [[PORTAL_WT!Space_Mining_In_Minnesota]] — the spine this portal serves — and its flagship [[WT!Space_Mining_In_Minnesota]] (MTN's room). **Siblings in service:** [[PORTAL_Computation]] · [[PORTAL_Physics]] · [[PORTAL_Chemistry]] · [[PORTAL_Space]] · [[PORTAL_Mining]] · [[PORTAL_Manufacturing]] · [[PORTAL_Minnesota]] — with [[PORTAL_Computation]] the megalith under all of them. **History · Lists · Glossaries** (verified against the English Wikipedia API on 2026-09-22 (exact titles)): [[History_of_structural_engineering]] · [[History_of_materials_science]] · [[History_of_measurement]] · [[Glossary_of_mechanical_engineering]] · [[Glossary_of_engineering:_A–L]] · [[Glossary_of_engineering:_M–Z]] · [[Glossary_of_mill_machinery]]. **Rooms already on the index** ([[PORTAL_INDEX]] rows): [[PORTAL_Centers_of_Excellence]] · [[PORTAL_WT!Thury_Hydrodynamics_Compendium]] · [[PORTAL_Solar_System]] · [[PORTAL_Rocketry]] · [[PORTAL_Energy]] · [[PORTAL_Materials_science]] · [[PORTAL_Robotics]] · [[PORTAL_Geometry]]. ### Notes (in service) 1. **What this page is.** The Engineering spine *in service of* [[PORTAL_WT!Space_Mining_In_Minnesota]]: thirty sections chosen for what they supply to the apex, each with its Main article, its See-also children, a one-line sim brief with the equation the sim runs and the apex sections it serves. It is a skeletal outline by design (MTN, 2026-09-22): less advanced models populate the child articles and their sims from the two worklists at the foot, with the hero as the model of the house pattern. 2. **Slugs.** Every article slug is the exact current English Wikipedia title, resolved through the API on 2026-09-22 (redirects followed to their targets, disambiguation and non-existent titles dropped before the spine was fixed); `rev:` on every worklist row pins the revision. 3. **Build state.** The hero `engineering/Watt_Line.html` is built and gated SHIP (rendered, zero console, sweep clean, 11 draw calls; `tools/gate.sh`, 2026-09-22) and its 36 URL states were walked headless; it is staged, not deployed — production is MTN's (style guide §12.10: a player replaces a placeholder only after a 200-check). Of the thirty section sims, 8 reuse a player a portal page already carries (Stress_(mechanics) on Engineering, Hooke's_law on Engineering, Fatigue_(material) on Engineering, Gear on Engineering, Hydraulics on Engineering, Engineering_tolerance on Engineering, Finite_element_method on Engineering, Reliability_engineering on Engineering), 0 reuse the apex spine's (none), and the other 22 are queued as specs of their own. 4. **One article, several portals.** A section whose Main article is also an apex Main article is a *reuse* row: the apex owns the article and the sim, this portal adds membership (shared contract §1); the same holds for See-also titles the apex already carries. Available reads 0 on this page for the same reason as on the apex: nothing is verified live yet. 5. **Append-only.** This block was appended to the existing `PORTAL_Engineering` page on 2026-09-22 under its own markers; nothing above the markers was edited. The in-service spine is a second spine on the page, not a replacement of the first. 6. **Worklist mechanics.** Rows are claimed, heart-beaten and closed only through the queue tool on the shard (`Style Guide and Worklist/PORTAL_Engineering.worklist.md`); a row turns ✅ only with a live URL. The two lists here, the shard and `worklists/PORTAL_Engineering/jobs.json` are projections of one record, regenerated together by `build_portals9.py` (kept with the item-9 checkpoint).  ## Microsim libraries and worklists Coverage: complete within declared bounds — the 30 sections and 93 See-also associations of this portal's spine (123 distinct titles), not a crawl of Wikipedia. Examined: every title against the English Wikipedia API on 2026-09-22 (redirects followed, missing and disambiguation titles dropped before the spine was fixed), the apex spine's rows (for shared articles), the three existing portal pages (for players already carried), the framework's `specs/sims/` (the hero built) and the run's book shelf. Pending/failed: the live 200-check of the hero and of the existing players is not performed — production deploy is MTN's and the sim host was not in this run's approved browser-pane sites (item 10). Last evaluated: 2026-09-22 (this run). Stopping rule: the spine's rows; no title outside them was scored. Published assets and pending work are counted separately. Unknown coverage is not zero opportunity. ### Reader-facing libraries | Library | Available artifacts | Ready jobs | In progress/review | Needs enrichment | Candidates | Failed/stale | Worklist | |---|---:|---:|---:|---:|---:|---:|---| | Three.js (primary presentation; the spine rule, style guide §7.5) | 0 (no current artifact verified live) | 22 (section sims with a brief and a pinned revision) | 1 (The Watt Line, the hero: built and gated SHIP, staged, awaiting MTN's publish) | 14 (6 rows owned by the apex or a sibling portal awaiting that build, 8 existing players and the shared rows awaiting a 200-check) | 87 (See-also variants) | 0 | `worklists/PORTAL_Engineering/threejs/worklist.md` | | p5.js (primary presentation) | 0 | 0 | 0 | 0 | 0 — 0 found within this scan: the spine rule routes every section sim to three.js | 0 | `worklists/PORTAL_Engineering/p5js/worklist.md` | | Native portrait (asset, no JavaScript) | 0 | 0 | 0 | 2 (biography rows: Commons portrait, licence and credit not yet verified, §14) | 0 | 0 | `worklists/PORTAL_Engineering/native-portrait/worklist.md` | | 30 other registered libraries | Not scanned | Not scanned | — | — | — | — | `worklists/PORTAL_Engineering/INDEX.md` (one folder each; the profile's `other` list names jscad, rapier, matterjs, plotly, d3 as candidates — no job proposed this run) | ### Integration and platform services | Library/service | Approved components | Open work | Blocked work | Consumers | Worklist | |---|---:|---:|---:|---|---| | `libs/wt-hero.js` (integration: the Master Portal Hero) | 1 (the template; nine instances built and gated SHIP across the nine portals) | 0 | 0 | ENG-HERO | `worklists/PORTAL_Engineering/threejs/worklist.md` § Integration | | `libs/wt-isru.js` (integration: the ISRU model library, 190 checks) | 1 | 0 | 0 | ENG-HERO and the section sims that name `isru` | same | | `libs/wt-mech.js` (integration: machines, gravity, orbits) | 1 (existing framework module) | 0 | 0 | ENG-HERO | same | | `specs/portals/PORTAL_Engineering.pack.json` (integration: kicker, palette, camera, `permissions_up_front`; set `engineering/`) | 1 | 0 | 0 | every `engineering/` spec | same | | `tools/shots_hero.mjs` + `tools/bench.js` (service: the headless state walk and the gate) | 1 | 0 | 0 | the hero (36 states walked, console empty) | same | | `_3d_deploy_stage/deploy_spacemining.sh` (service: stage + MTN's production publish + URL verification, one script for all nine sets) | 0 | 1 (item 10) | 1 (production is MTN's) | the hero and every player above | same | Full index: `Style Guide and Worklist/worklists/PORTAL_Engineering/INDEX.md` (resolved local vault path; no public URL is claimed for it). This section indexes existing outputs and proposed work; it does not itself publish a microsim. ## Microsim Worklist > **Permissions to request up front:** see the block at the head of this page — ask for all of them in one round before the first tool call (browser-pane sites, vault folder, no WT! scope needed here, no deletes, deploy is MTN's). Row grammar (style guide §11.1): ``- [ ] [[Slug]] — engine · pattern · `equation` · what the viewer does · id · prio · type · rev``. Lifecycle markers (§11.2) are appended, never edited into the row. `type:` is `hero` (the Master Portal Hero instance), `section sim` (a spec of its own in `specs/sims/`, set `engineering/`), `existing sim` (a player one of the portal pages already carries — the row names which — to re-verify), `reuse` (a section whose article and sim belong to the apex spine `WT!Space_Mining_In_Minnesota` — this portal adds membership, never a second build), `variant` (a See-also article's sim, `extends` the section's spec) and, on the Computation page, `brief` (a reviewer-sourced brief with book locators). `serves:SMM n` names the apex sections the row is in service of. The canonical record is `worklists/PORTAL_Engineering/jobs.json`; this list and the shard `Style Guide and Worklist/PORTAL_Engineering.worklist.md` are projections of it, regenerated together by `build_portals9.py`. ### Microsim To Do #### The hero - [ ] [[PORTAL_Engineering]] — three · Master Portal Hero (chain+bars+ledger) · `ledger per stage` · the power at a machine's terminals walked through motor, gearbox, bearings, drivetrain, tool, work, heat on five machines; 36 URL states · id:ENG-HERO · prio:A · type:hero · libs:isru,mech,hero *🧪 built SHIP 2026-09-22 — 36 states walked headless (`tools/shots_hero.mjs`), staged in `Style Guide and Worklist/MICROSIM_GUIDE/site/engineering/Watt_Line.html`, awaiting MTN's production publish* #### Priority A — the thirty section sims (22 new, 0 reused from the apex or a sibling portal, 8 existing players) - [ ] [[Stress_(mechanics)]] — three · existing player + in-service preset · `sigma = F / A` · a blade tip in rock: the normal and shear stress on a cut face, Mohr's circle turning to the worst plane · id:ENG-001 · prio:A · type:existing sim · rev:1370311866 · section:1 (Stress) · serves:SMM 15 · existing:`engineering/Stress_(mechanics).html` (this portal's existing player; 200-check before reuse) - [ ] [[Hooke's_law]] — three · existing player + in-service preset · `F = k x` · a spring, a bar, a tether: force proportional to stretch until it is not · id:ENG-002 · prio:A · type:existing sim · rev:1375736650 · section:2 (Hooke's law) · serves:SMM 10,24 · existing:`engineering/Hooke's_law.html` (this portal's existing player; 200-check before reuse) - [ ] [[Compressive_strength]] — three · section sim · `sigma_c = F_max / A` · UCS 100 MPa rock against 250 MPa taconite against a sintered regolith brick: the strength that sets the cutting force · id:ENG-003 · prio:A · type:section sim · rev:1366678192 · section:3 (Compressive strength) · serves:SMM 15,22 · apex:SMM-181 (the apex lists this title as a See-also variant, candidate; this section sim supersedes it — when it ships, close the apex row as a reuse of this one) - [ ] [[Fatigue_(material)]] — three · existing player + in-service preset · `N_f = f(sigma_a)` · a bucket tooth cycled a million times: the S-N curve and the crack that grows a little every dig · id:ENG-004 · prio:A · type:existing sim · rev:1372946764 · section:4 (Fatigue) · serves:SMM 15,24 · existing:`matter/Fatigue_(material).html` (this portal's existing player; 200-check before reuse) - [ ] [[Beam_(structure)]] — three · section sim · `M = E I d2y/dx2` · the excavator's boom and the radiator's strut: bending stress and deflection, buckling of a slender column at one-sixth g · id:ENG-005 · prio:A · type:section sim · rev:1359179589 · section:5 (Beam) · serves:SMM 15,27 - [ ] [[Machine]] — three · section sim · `MA = F_out / F_in` · lever, wheel, screw: the six simple machines and the advantage each buys, the excavator as a chain of them · id:ENG-006 · prio:A · type:section sim · rev:1372733160 · section:6 (Machine) · serves:SMM 15 - [ ] [[Gear]] — three · existing player + in-service preset · `T2/T1 = N2/N1` · the mill's drive: ratio, torque and speed trading places through a gear train; efficiency per mesh · id:ENG-007 · prio:A · type:existing sim · rev:1376154750 · section:7 (Gear) · serves:SMM 16,24 · existing:`engineering/Gear.html` (this portal's existing player; 200-check before reuse) - [ ] [[Bearing_(mechanical)]] — three · section sim · `T_f = mu F r` · friction in a rolling bearing and a plain bearing in vacuum: no oil film, dry lubricants, the heat that has nowhere to go · id:ENG-008 · prio:A · type:section sim · rev:1366672841 · section:8 (Bearing) · serves:SMM 24 - [ ] [[Excavator]] — three · section sim · `F_h = f(alpha, phi, h_i, g)` · the digger's cycle: dig, swing, dump, return — the bucket force from the Delft model, the cycle time from the drives · id:ENG-009 · prio:A · type:section sim · rev:1375580667 · section:9 (Excavator) · serves:SMM 11,15 - [ ] [[Conveyor_belt]] — three · section sim · `Q = rho A v` · tonnes per hour from belt speed, width and burden; the lunar case with a sixth of the weight to hold the rock down · id:ENG-010 · prio:A · type:section sim · rev:1373776099 · section:10 (Conveyor belt) · serves:SMM 11,16 - [ ] [[Electric_motor]] — three · section sim · `P = T omega` · torque and speed from voltage and current: the motor curve, the efficiency map, the mill's 5 MW · id:ENG-011 · prio:A · type:section sim · rev:1374766051 · section:11 (Electric motor) · serves:SMM 16,24 - [ ] [[Linear_motor]] — three · section sim · `v = sqrt(2 a L)` · the mass driver as a linear motor: coil by coil, the bucket accelerates; exit speed from track length and acceleration · id:ENG-012 · prio:A · type:section sim · rev:1374761198 · section:12 (Linear motor) · serves:SMM 10 - [ ] [[Solenoid]] — three · section sim · `B = mu0 n I` · the field inside a coil and the energy it stores: the capacitor bank's joules per shot · id:ENG-013 · prio:A · type:section sim · rev:1375710896 · section:13 (Solenoid) · serves:SMM 10 - [ ] [[Electric_battery]] — three · section sim · `E = sum P dt` · the lunar night, 354 hours long: kilowatt-hours per kilogram against the night's demand; when fission beats batteries · id:ENG-014 · prio:A · type:section sim · rev:1373978617 · section:14 (Battery) · serves:SMM 26 - [ ] [[Hydraulics]] — three · existing player + in-service preset · `F = p A` · Pascal's law in the excavator's arm: pressure times area, the cylinder's force, the fluid that freezes at the pole · id:ENG-015 · prio:A · type:existing sim · rev:1367051871 · section:15 (Hydraulics) · serves:SMM 15 · existing:`engineering/Hydraulics.html` (this portal's existing player; 200-check before reuse) - [ ] [[Radiator]] — three · section sim · `A = Q / (eps sigma (T^4 - T_sink^4))` · the radiator equation with a fin: area against temperature, the mass per kilowatt rejected · id:ENG-016 · prio:A · type:section sim · rev:1373629056 · section:16 (Radiator) · serves:SMM 27 - [ ] [[Thermal_insulation]] — three · section sim · `q = dT / R` · multi-layer insulation on a cold trap's reactor: layers against heat leak, regolith itself as insulation · id:ENG-017 · prio:A · type:section sim · rev:1375683766 · section:17 (Thermal insulation) · serves:SMM 20,27 - [ ] [[Heat_exchanger]] — three · section sim · `Q = U A dT_lm` · recover the reactor's heat: counterflow, the log-mean temperature difference, the energy saved per kilogram · id:ENG-018 · prio:A · type:section sim · rev:1375531639 · section:18 (Heat exchanger) · serves:SMM 20 - [ ] [[Solar_furnace]] — three · section sim · `Q = m c dT + m L` · the pellet plant's induration furnace and a solar furnace on the Moon: 1,300 C by fuel, by arc, by mirror · id:ENG-019 · prio:A · type:section sim · rev:1311736603 · section:19 (Furnace) · serves:SMM 22 · apex:SMM-226 (the apex lists this title as a See-also variant, candidate; this section sim supersedes it — when it ships, close the apex row as a reuse of this one) - [ ] [[Thermal_expansion]] — three · section sim · `dL = alpha L dT` · a machine that sees 390 K by day and 100 K by night: expansion, thermal stress, the fit that binds · id:ENG-020 · prio:A · type:section sim · rev:1368853368 · section:20 (Thermal expansion) · serves:SMM 24,27 - [ ] [[Engineering_tolerance]] — three · existing player + in-service preset · `t_stack = sqrt(sum t_i^2)` · ten parts in a stack: the root-sum-square against the worst case; the fit that a machinist a million kilometres away cannot adjust · id:ENG-021 · prio:A · type:existing sim · rev:1315161613 · section:21 (Engineering tolerance) · serves:SMM 24 · existing:`engineering/Engineering_tolerance.html` (this portal's existing player; 200-check before reuse) - [ ] [[Metrology]] — three · section sim · `u_c = sqrt(sum u_i^2)` · measuring the part you made: the CMM, the gauge, the uncertainty budget · id:ENG-022 · prio:A · type:section sim · rev:1373568765 · section:22 (Metrology) · serves:SMM 24 · apex:SMM-236 (the apex lists this title as a See-also variant, candidate; this section sim supersedes it — when it ships, close the apex row as a reuse of this one) - [ ] [[Control_system]] — three · section sim · `u = Kp e + Ki int e + Kd de/dt` · a furnace at 1,300 C and a lathe on a curve: the PID loop, its gains, its overshoot · id:ENG-023 · prio:A · type:section sim · rev:1364618081 · section:23 (Control system) · serves:SMM 22,24 - [ ] [[Finite_element_method]] — three · existing player + in-service preset · `K u = f` · the boom meshed and loaded: stress in every element, the picture the hand calculation approximates · id:ENG-024 · prio:A · type:existing sim · rev:1373533703 · section:24 (Finite element method) · serves:SMM 15,27 · existing:`engineering/Finite_element_method.html` (this portal's existing player; 200-check before reuse) - [ ] [[Reliability_engineering]] — three · existing player + in-service preset · `R(t) = exp(-lambda t)` · a machine with no repair shop: MTBF, the bathtub curve, the spare-part mass the printer replaces · id:ENG-025 · prio:A · type:existing sim · rev:1344593273 · section:25 (Reliability engineering) · serves:SMM 21,25 · existing:`Reliability_engineering.html` (this portal's existing player; 200-check before reuse) - [ ] [[Systems_engineering]] — three · section sim · `mass, power, cost, risk` · the ISRU plant as a system: requirements, interfaces, the trade between launch mass and complexity · id:ENG-026 · prio:A · type:section sim · rev:1374062683 · section:26 (Systems engineering) · serves:SMM 1,29 - [ ] [[Robotics]] — three · section sim · `x = f(theta)` · a digger that nobody drives: light-time delay, autonomy, the arm's kinematics · id:ENG-027 · prio:A · type:section sim · rev:1375005708 · section:27 (Robotics) · serves:SMM 11,25 - [ ] [[Mining_engineering]] — three · section sim · `cost per ton` · the discipline that owns the pit: Hoover's and Peele's engineering, applied where there is no air · id:ENG-028 · prio:A · type:section sim · rev:1368378670 · section:28 (Mining engineering) · serves:SMM 11 · apex:SMM-161 (the apex lists this title as a See-also variant, candidate; this section sim supersedes it — when it ships, close the apex row as a reuse of this one) - [ ] [[W._J._M._Rankine]] — three · section sim · `K_p = (1 + sin phi)/(1 - sin phi)` · the Manual of Applied Mechanics: friction, earth pressure, the heap at its friction angle — Rankine's articles behind the regolith sim · id:ENG-029 · prio:A · type:section sim · rev:1372006024 · section:29 (William John Macquorn Rankine) · serves:SMM 14 - [ ] [[Vitruvius]] — three · section sim · `MA = d_in / d_out` · the Ten Books on Architecture: machines for lifting, water and the first engineering handbook on the shelf · id:ENG-030 · prio:A · type:section sim · rev:1371786545 · section:30 (Vitruvius) · serves:SMM 15 #### Priority B — See-also variants (93 rows, one per distinct title) - [ ] [[Strain_(mechanics)]] — three · variant of ENG-001 · `sigma = F / A` · the Stress sim (ENG-001) opened on a preset or annotation for Strain (mechanics) — `extends specs/sims/Stress_(mechanics).json` as `specs/variants/Strain_(mechanics).json` · id:ENG-101 · prio:B · type:variant · rev:1365996368 · section:1 (Stress) - [ ] [[Shear_stress]] — three · variant of ENG-001 · `sigma = F / A` · the Stress sim (ENG-001) opened on a preset or annotation for Shear stress — `extends specs/sims/Stress_(mechanics).json` as `specs/variants/Shear_stress.json` · id:ENG-102 · prio:B · type:variant · rev:1343187277 · section:1 (Stress) - [ ] [[Mohr's_circle]] — three · variant of ENG-001 · `sigma = F / A` · the Stress sim (ENG-001) opened on a preset or annotation for Mohr's circle — `extends specs/sims/Stress_(mechanics).json` as `specs/variants/Mohr's_circle.json` · id:ENG-103 · prio:B · type:variant · rev:1330528049 · section:1 (Stress) - [ ] [[Yield_(engineering)]] — three · variant of ENG-001 · `sigma = F / A` · the Stress sim (ENG-001) opened on a preset or annotation for Yield (engineering) — `extends specs/sims/Stress_(mechanics).json` as `specs/variants/Yield_(engineering).json` · id:ENG-104 · prio:B · type:variant · rev:1368584646 · section:1 (Stress) - [ ] [[Young's_modulus]] — three · variant of ENG-002 · `F = k x` · the Hooke's law sim (ENG-002) opened on a preset or annotation for Young's modulus — `extends specs/sims/Hooke's_law.json` as `specs/variants/Young's_modulus.json` · id:ENG-105 · prio:B · type:variant · rev:1368470046 · section:2 (Hooke's law) - [ ] [[Spring_(device)]] — three · variant of ENG-002 · `F = k x` · the Hooke's law sim (ENG-002) opened on a preset or annotation for Spring (device) — `extends specs/sims/Hooke's_law.json` as `specs/variants/Spring_(device).json` · id:ENG-106 · prio:B · type:variant · rev:1367387211 · section:2 (Hooke's law) - [ ] [[Stiffness]] — three · variant of ENG-002 · `F = k x` · the Hooke's law sim (ENG-002) opened on a preset or annotation for Stiffness — `extends specs/sims/Hooke's_law.json` as `specs/variants/Stiffness.json` · id:ENG-107 · prio:B · type:variant · rev:1369105655 · section:2 (Hooke's law) - [ ] [[Ultimate_tensile_strength]] — three · variant of ENG-003 · `sigma_c = F_max / A` · the Compressive strength sim (ENG-003) opened on a preset or annotation for Ultimate tensile strength — `extends specs/sims/Compressive_strength.json` as `specs/variants/Ultimate_tensile_strength.json` · id:ENG-108 · prio:B · type:variant · rev:1356978255 · section:3 (Compressive strength) - [ ] [[Brittleness]] — three · variant of ENG-003 · `sigma_c = F_max / A` · the Compressive strength sim (ENG-003) opened on a preset or annotation for Brittleness — `extends specs/sims/Compressive_strength.json` as `specs/variants/Brittleness.json` · id:ENG-109 · prio:B · type:variant · rev:1348177754 · section:3 (Compressive strength) - [ ] [[Rock_mass_rating]] — three · variant of ENG-003 · `sigma_c = F_max / A` · the Compressive strength sim (ENG-003) opened on a preset or annotation for Rock mass rating — `extends specs/sims/Compressive_strength.json` as `specs/variants/Rock_mass_rating.json` · id:ENG-110 · prio:B · type:variant · rev:1333206116 · section:3 (Compressive strength) - [ ] [[Fracture_mechanics]] — three · variant of ENG-004 · `N_f = f(sigma_a)` · the Fatigue sim (ENG-004) opened on a preset or annotation for Fracture mechanics — `extends specs/sims/Fatigue_(material).json` as `specs/variants/Fracture_mechanics.json` · id:ENG-111 · prio:B · type:variant · rev:1362286178 · section:4 (Fatigue) - [ ] [[Bending]] — three · variant of ENG-005 · `M = E I d2y/dx2` · the Beam sim (ENG-005) opened on a preset or annotation for Bending — `extends specs/sims/Beam_(structure).json` as `specs/variants/Bending.json` · id:ENG-112 · prio:B · type:variant · rev:1351473367 · section:5 (Beam) - [ ] [[Euler–Bernoulli_beam_theory]] — three · variant of ENG-005 · `M = E I d2y/dx2` · the Beam sim (ENG-005) opened on a preset or annotation for Euler–Bernoulli beam theory — `extends specs/sims/Beam_(structure).json` as `specs/variants/Euler–Bernoulli_beam_theory.json` · id:ENG-113 · prio:B · type:variant · rev:1373956269 · section:5 (Beam) - [ ] [[Buckling]] — three · variant of ENG-005 · `M = E I d2y/dx2` · the Beam sim (ENG-005) opened on a preset or annotation for Buckling — `extends specs/sims/Beam_(structure).json` as `specs/variants/Buckling.json` · id:ENG-114 · prio:B · type:variant · rev:1362996017 · section:5 (Beam) - [ ] [[Deflection_(engineering)]] — three · variant of ENG-005 · `M = E I d2y/dx2` · the Beam sim (ENG-005) opened on a preset or annotation for Deflection (engineering) — `extends specs/sims/Beam_(structure).json` as `specs/variants/Deflection_(engineering).json` · id:ENG-115 · prio:B · type:variant · rev:1315389755 · section:5 (Beam) - [ ] [[Simple_machine]] — three · variant of ENG-006 · `MA = F_out / F_in` · the Machine sim (ENG-006) opened on a preset or annotation for Simple machine — `extends specs/sims/Machine.json` as `specs/variants/Simple_machine.json` · id:ENG-116 · prio:B · type:variant · rev:1369419169 · section:6 (Machine) - [ ] [[Mechanical_advantage]] — three · variant of ENG-006 · `MA = F_out / F_in` · the Machine sim (ENG-006) opened on a preset or annotation for Mechanical advantage — `extends specs/sims/Machine.json` as `specs/variants/Mechanical_advantage.json` · id:ENG-117 · prio:B · type:variant · rev:1374324181 · section:6 (Machine) - [ ] [[Mechanism_(engineering)]] — three · variant of ENG-006 · `MA = F_out / F_in` · the Machine sim (ENG-006) opened on a preset or annotation for Mechanism (engineering) — `extends specs/sims/Machine.json` as `specs/variants/Mechanism_(engineering).json` · id:ENG-118 · prio:B · type:variant · rev:1373781083 · section:6 (Machine) - [ ] [[Gear_train]] — three · variant of ENG-007 · `T2/T1 = N2/N1` · the Gear sim (ENG-007) opened on a preset or annotation for Gear train — `extends specs/sims/Gear.json` as `specs/variants/Gear_train.json` · id:ENG-119 · prio:B · type:variant · rev:1362680818 · section:7 (Gear) - [ ] [[Involute_gear]] — three · variant of ENG-007 · `T2/T1 = N2/N1` · the Gear sim (ENG-007) opened on a preset or annotation for Involute gear — `extends specs/sims/Gear.json` as `specs/variants/Involute_gear.json` · id:ENG-120 · prio:B · type:variant · rev:1357422837 · section:7 (Gear) - [ ] [[Torque]] — three · variant of ENG-007 · `T2/T1 = N2/N1` · the Gear sim (ENG-007) opened on a preset or annotation for Torque — `extends specs/sims/Gear.json` as `specs/variants/Torque.json` · id:ENG-121 · prio:B · type:variant · rev:1373522769 · section:7 (Gear) - [ ] [[Rolling-element_bearing]] — three · variant of ENG-008 · `T_f = mu F r` · the Bearing sim (ENG-008) opened on a preset or annotation for Rolling-element bearing — `extends specs/sims/Bearing_(mechanical).json` as `specs/variants/Rolling-element_bearing.json` · id:ENG-122 · prio:B · type:variant · rev:1361059116 · section:8 (Bearing) - [ ] [[Plain_bearing]] — three · variant of ENG-008 · `T_f = mu F r` · the Bearing sim (ENG-008) opened on a preset or annotation for Plain bearing — `extends specs/sims/Bearing_(mechanical).json` as `specs/variants/Plain_bearing.json` · id:ENG-123 · prio:B · type:variant · rev:1370581706 · section:8 (Bearing) - [ ] [[Lubrication]] — three · variant of ENG-008 · `T_f = mu F r` · the Bearing sim (ENG-008) opened on a preset or annotation for Lubrication — `extends specs/sims/Bearing_(mechanical).json` as `specs/variants/Lubrication.json` · id:ENG-124 · prio:B · type:variant · rev:1368801522 · section:8 (Bearing) - [ ] [[Tribology]] — three · variant of ENG-008 · `T_f = mu F r` · the Bearing sim (ENG-008) opened on a preset or annotation for Tribology — `extends specs/sims/Bearing_(mechanical).json` as `specs/variants/Tribology.json` · id:ENG-125 · prio:B · type:variant · rev:1373312982 · section:8 (Bearing) - [ ] [[Bucket-wheel_excavator]] — three · variant of ENG-009 · `F_h = f(alpha, phi, h_i, g)` · the Excavator sim (ENG-009) opened on a preset or annotation for Bucket-wheel excavator — `extends specs/sims/Excavator.json` as `specs/variants/Bucket-wheel_excavator.json` · id:ENG-126 · prio:B · type:variant · rev:1375073893 · section:9 (Excavator) - [ ] [[Dragline_excavator]] — three · variant of ENG-009 · `F_h = f(alpha, phi, h_i, g)` · the Excavator sim (ENG-009) opened on a preset or annotation for Dragline excavator — `extends specs/sims/Excavator.json` as `specs/variants/Dragline_excavator.json` · id:ENG-127 · prio:B · type:variant · rev:1353631617 · section:9 (Excavator) - [ ] [[Loader_(equipment)]] — three · variant of ENG-009 · `F_h = f(alpha, phi, h_i, g)` · the Excavator sim (ENG-009) opened on a preset or annotation for Loader (equipment) — `extends specs/sims/Excavator.json` as `specs/variants/Loader_(equipment).json` · id:ENG-128 · prio:B · type:variant · rev:1361997893 · section:9 (Excavator) - [ ] [[Bulk_material_handling]] — three · variant of ENG-010 · `Q = rho A v` · the Conveyor belt sim (ENG-010) opened on a preset or annotation for Bulk material handling — `extends specs/sims/Conveyor_belt.json` as `specs/variants/Bulk_material_handling.json` · id:ENG-129 · prio:B · type:variant · rev:1275024064 · section:10 (Conveyor belt) - [ ] [[Screw_conveyor]] — three · variant of ENG-010 · `Q = rho A v` · the Conveyor belt sim (ENG-010) opened on a preset or annotation for Screw conveyor — `extends specs/sims/Conveyor_belt.json` as `specs/variants/Screw_conveyor.json` · id:ENG-130 · prio:B · type:variant · rev:1360734827 · section:10 (Conveyor belt) - [ ] [[Bucket_elevator]] — three · variant of ENG-010 · `Q = rho A v` · the Conveyor belt sim (ENG-010) opened on a preset or annotation for Bucket elevator — `extends specs/sims/Conveyor_belt.json` as `specs/variants/Bucket_elevator.json` · id:ENG-131 · prio:B · type:variant · rev:1325712395 · section:10 (Conveyor belt) - [ ] [[Brushless_DC_electric_motor]] — three · variant of ENG-011 · `P = T omega` · the Electric motor sim (ENG-011) opened on a preset or annotation for Brushless DC electric motor — `extends specs/sims/Electric_motor.json` as `specs/variants/Brushless_DC_electric_motor.json` · id:ENG-132 · prio:B · type:variant · rev:1375439361 · section:11 (Electric motor) - [ ] [[Efficiency]] — three · variant of ENG-011 · `P = T omega` · the Electric motor sim (ENG-011) opened on a preset or annotation for Efficiency — `extends specs/sims/Electric_motor.json` as `specs/variants/Efficiency.json` · id:ENG-133 · prio:B · type:variant · rev:1365456617 · section:11 (Electric motor) - [ ] [[Coilgun]] — three · variant of ENG-012 · `v = sqrt(2 a L)` · the Linear motor sim (ENG-012) opened on a preset or annotation for Coilgun — `extends specs/sims/Linear_motor.json` as `specs/variants/Coilgun.json` · id:ENG-134 · prio:B · type:variant · rev:1354179401 · section:12 (Linear motor) - [ ] [[Railgun]] — three · variant of ENG-012 · `v = sqrt(2 a L)` · the Linear motor sim (ENG-012) opened on a preset or annotation for Railgun — `extends specs/sims/Linear_motor.json` as `specs/variants/Railgun.json` · id:ENG-135 · prio:B · type:variant · rev:1376205319 · section:12 (Linear motor) - [ ] [[Maglev]] — three · variant of ENG-012 · `v = sqrt(2 a L)` · the Linear motor sim (ENG-012) opened on a preset or annotation for Maglev — `extends specs/sims/Linear_motor.json` as `specs/variants/Maglev.json` · id:ENG-136 · prio:B · type:variant · rev:1375450083 · section:12 (Linear motor) - [ ] [[Inductor]] — three · variant of ENG-013 · `B = mu0 n I` · the Solenoid sim (ENG-013) opened on a preset or annotation for Inductor — `extends specs/sims/Solenoid.json` as `specs/variants/Inductor.json` · id:ENG-137 · prio:B · type:variant · rev:1375788705 · section:13 (Solenoid) - [ ] [[Inductance]] — three · variant of ENG-013 · `B = mu0 n I` · the Solenoid sim (ENG-013) opened on a preset or annotation for Inductance — `extends specs/sims/Solenoid.json` as `specs/variants/Inductance.json` · id:ENG-138 · prio:B · type:variant · rev:1372308482 · section:13 (Solenoid) - [ ] [[Magnetic_flux]] — three · variant of ENG-013 · `B = mu0 n I` · the Solenoid sim (ENG-013) opened on a preset or annotation for Magnetic flux — `extends specs/sims/Solenoid.json` as `specs/variants/Magnetic_flux.json` · id:ENG-139 · prio:B · type:variant · rev:1367678492 · section:13 (Solenoid) - [ ] [[Lithium-ion_battery]] — three · variant of ENG-014 · `E = sum P dt` · the Battery sim (ENG-014) opened on a preset or annotation for Lithium-ion battery — `extends specs/sims/Electric_battery.json` as `specs/variants/Lithium-ion_battery.json` · id:ENG-140 · prio:B · type:variant · rev:1375830392 · section:14 (Battery) - [ ] [[Energy_density]] — three · variant of ENG-014 · `E = sum P dt` · the Battery sim (ENG-014) opened on a preset or annotation for Energy density — `extends specs/sims/Electric_battery.json` as `specs/variants/Energy_density.json` · id:ENG-141 · prio:B · type:variant · rev:1366889538 · section:14 (Battery) - [ ] [[Specific_energy]] — three · variant of ENG-014 · `E = sum P dt` · the Battery sim (ENG-014) opened on a preset or annotation for Specific energy — `extends specs/sims/Electric_battery.json` as `specs/variants/Specific_energy.json` · id:ENG-142 · prio:B · type:variant · rev:1325119006 · section:14 (Battery) - [ ] [[Hydraulic_cylinder]] — three · variant of ENG-015 · `F = p A` · the Hydraulics sim (ENG-015) opened on a preset or annotation for Hydraulic cylinder — `extends specs/sims/Hydraulics.json` as `specs/variants/Hydraulic_cylinder.json` · id:ENG-143 · prio:B · type:variant · rev:1373421738 · section:15 (Hydraulics) - [ ] [[Pascal's_law]] — three · variant of ENG-015 · `F = p A` · the Hydraulics sim (ENG-015) opened on a preset or annotation for Pascal's law — `extends specs/sims/Hydraulics.json` as `specs/variants/Pascal's_law.json` · id:ENG-144 · prio:B · type:variant · rev:1363145553 · section:15 (Hydraulics) - [ ] [[Hydraulic_machinery]] — three · variant of ENG-015 · `F = p A` · the Hydraulics sim (ENG-015) opened on a preset or annotation for Hydraulic machinery — `extends specs/sims/Hydraulics.json` as `specs/variants/Hydraulic_machinery.json` · id:ENG-145 · prio:B · type:variant · rev:1374318756 · section:15 (Hydraulics) - [ ] [[Spacecraft_thermal_control]] — three · reuse of SMM-027 · `A = Q / (eps sigma (T^4 - T_sink^4))` · owned by the apex spine as SMM-027 (Main article); this portal adds membership only · id:ENG-146 · prio:B · type:reuse · rev:1344666664 · section:16 (Radiator) - [ ] [[Heat_pipe]] — three · variant of ENG-016 · `A = Q / (eps sigma (T^4 - T_sink^4))` · the Radiator sim (ENG-016) opened on a preset or annotation for Heat pipe — `extends specs/sims/Radiator.json` as `specs/variants/Heat_pipe.json` · id:ENG-147 · prio:B · type:variant · rev:1368764634 · section:16 (Radiator) - [ ] [[Radiator_(engine_cooling)]] — three · variant of ENG-016 · `A = Q / (eps sigma (T^4 - T_sink^4))` · the Radiator sim (ENG-016) opened on a preset or annotation for Radiator (engine cooling) — `extends specs/sims/Radiator.json` as `specs/variants/Radiator_(engine_cooling).json` · id:ENG-148 · prio:B · type:variant · rev:1375606111 · section:16 (Radiator) - [ ] [[Multi-layer_insulation]] — three · variant of ENG-017 · `q = dT / R` · the Thermal insulation sim (ENG-017) opened on a preset or annotation for Multi-layer insulation — `extends specs/sims/Thermal_insulation.json` as `specs/variants/Multi-layer_insulation.json` · id:ENG-149 · prio:B · type:variant · rev:1373023315 · section:17 (Thermal insulation) - [ ] [[Thermal_conductivity_and_resistivity]] — three · variant of ENG-017 · `q = dT / R` · the Thermal insulation sim (ENG-017) opened on a preset or annotation for Thermal conductivity and resistivity — `extends specs/sims/Thermal_insulation.json` as `specs/variants/Thermal_conductivity_and_resistivity.json` · id:ENG-150 · prio:B · type:variant · rev:1374231229 · section:17 (Thermal insulation) - [ ] [[R-value_(insulation)]] — three · variant of ENG-017 · `q = dT / R` · the Thermal insulation sim (ENG-017) opened on a preset or annotation for R-value (insulation) — `extends specs/sims/Thermal_insulation.json` as `specs/variants/R-value_(insulation).json` · id:ENG-151 · prio:B · type:variant · rev:1375683636 · section:17 (Thermal insulation) - [ ] [[Countercurrent_exchange]] — three · variant of ENG-018 · `Q = U A dT_lm` · the Heat exchanger sim (ENG-018) opened on a preset or annotation for Countercurrent exchange — `extends specs/sims/Heat_exchanger.json` as `specs/variants/Countercurrent_exchange.json` · id:ENG-152 · prio:B · type:variant · rev:1365558993 · section:18 (Heat exchanger) - [ ] [[Logarithmic_mean_temperature_difference]] — three · variant of ENG-018 · `Q = U A dT_lm` · the Heat exchanger sim (ENG-018) opened on a preset or annotation for Logarithmic mean temperature difference — `extends specs/sims/Heat_exchanger.json` as `specs/variants/Logarithmic_mean_temperature_difference.json` · id:ENG-153 · prio:B · type:variant · rev:1369555987 · section:18 (Heat exchanger) - [ ] [[Heat_recovery_ventilation]] — three · variant of ENG-018 · `Q = U A dT_lm` · the Heat exchanger sim (ENG-018) opened on a preset or annotation for Heat recovery ventilation — `extends specs/sims/Heat_exchanger.json` as `specs/variants/Heat_recovery_ventilation.json` · id:ENG-154 · prio:B · type:variant · rev:1369528708 · section:18 (Heat exchanger) - [ ] [[Induction_heating]] — three · variant of ENG-019 · `Q = m c dT + m L` · the Furnace sim (ENG-019) opened on a preset or annotation for Induction heating — `extends specs/sims/Solar_furnace.json` as `specs/variants/Induction_heating.json` · id:ENG-155 · prio:B · type:variant · rev:1364504193 · section:19 (Furnace) - [ ] [[Electric_arc_furnace]] — three · variant of ENG-019 · `Q = m c dT + m L` · the Furnace sim (ENG-019) opened on a preset or annotation for Electric arc furnace — `extends specs/sims/Solar_furnace.json` as `specs/variants/Electric_arc_furnace.json` · id:ENG-156 · prio:B · type:variant · rev:1359507483 · section:19 (Furnace) - [ ] [[Kiln]] — three · variant of ENG-019 · `Q = m c dT + m L` · the Furnace sim (ENG-019) opened on a preset or annotation for Kiln — `extends specs/sims/Solar_furnace.json` as `specs/variants/Kiln.json` · id:ENG-157 · prio:B · type:variant · rev:1373821245 · section:19 (Furnace) - [ ] [[Thermal_stress]] — three · variant of ENG-020 · `dL = alpha L dT` · the Thermal expansion sim (ENG-020) opened on a preset or annotation for Thermal stress — `extends specs/sims/Thermal_expansion.json` as `specs/variants/Thermal_stress.json` · id:ENG-158 · prio:B · type:variant · rev:1328627048 · section:20 (Thermal expansion) - [ ] [[Bimetallic_strip]] — three · variant of ENG-020 · `dL = alpha L dT` · the Thermal expansion sim (ENG-020) opened on a preset or annotation for Bimetallic strip — `extends specs/sims/Thermal_expansion.json` as `specs/variants/Bimetallic_strip.json` · id:ENG-159 · prio:B · type:variant · rev:1367990031 · section:20 (Thermal expansion) - [ ] [[Tolerance_analysis]] — three · variant of ENG-021 · `t_stack = sqrt(sum t_i^2)` · the Engineering tolerance sim (ENG-021) opened on a preset or annotation for Tolerance analysis — `extends specs/sims/Engineering_tolerance.json` as `specs/variants/Tolerance_analysis.json` · id:ENG-160 · prio:B · type:variant · rev:1347049327 · section:21 (Engineering tolerance) - [ ] [[Interchangeable_parts]] — three · variant of ENG-021 · `t_stack = sqrt(sum t_i^2)` · the Engineering tolerance sim (ENG-021) opened on a preset or annotation for Interchangeable parts — `extends specs/sims/Engineering_tolerance.json` as `specs/variants/Interchangeable_parts.json` · id:ENG-161 · prio:B · type:variant · rev:1364850391 · section:21 (Engineering tolerance) - [ ] [[Engineering_fit]] — three · variant of ENG-021 · `t_stack = sqrt(sum t_i^2)` · the Engineering tolerance sim (ENG-021) opened on a preset or annotation for Engineering fit — `extends specs/sims/Engineering_tolerance.json` as `specs/variants/Engineering_fit.json` · id:ENG-162 · prio:B · type:variant · rev:1338122685 · section:21 (Engineering tolerance) - [ ] [[Geometric_dimensioning_and_tolerancing]] — three · variant of ENG-021 · `t_stack = sqrt(sum t_i^2)` · the Engineering tolerance sim (ENG-021) opened on a preset or annotation for Geometric dimensioning and tolerancing — `extends specs/sims/Engineering_tolerance.json` as `specs/variants/Geometric_dimensioning_and_tolerancing.json` · id:ENG-163 · prio:B · type:variant · rev:1362286596 · section:21 (Engineering tolerance) - [ ] [[Coordinate-measuring_machine]] — three · variant of ENG-022 · `u_c = sqrt(sum u_i^2)` · the Metrology sim (ENG-022) opened on a preset or annotation for Coordinate-measuring machine — `extends specs/sims/Metrology.json` as `specs/variants/Coordinate-measuring_machine.json` · id:ENG-164 · prio:B · type:variant · rev:1333129344 · section:22 (Metrology) - [ ] [[Calibration]] — three · variant of ENG-022 · `u_c = sqrt(sum u_i^2)` · the Metrology sim (ENG-022) opened on a preset or annotation for Calibration — `extends specs/sims/Metrology.json` as `specs/variants/Calibration.json` · id:ENG-165 · prio:B · type:variant · rev:1355776629 · section:22 (Metrology) - [ ] [[Gauge_block]] — three · variant of ENG-022 · `u_c = sqrt(sum u_i^2)` · the Metrology sim (ENG-022) opened on a preset or annotation for Gauge block — `extends specs/sims/Metrology.json` as `specs/variants/Gauge_block.json` · id:ENG-166 · prio:B · type:variant · rev:1367013863 · section:22 (Metrology) - [ ] [[Measurement_uncertainty]] — three · reuse of CMP-001 · `u_c = sqrt(sum u_i^2)` · owned by PORTAL_Computation as row CMP-001 — `computation/Measurement_uncertainty.html` (PORTAL_Computation's section sim, in its queue); this portal adds membership only · id:ENG-167 · prio:B · type:reuse · rev:1367370535 · section:22 (Metrology) - [ ] [[Control_theory]] — three · variant of ENG-023 · `u = Kp e + Ki int e + Kd de/dt` · the Control system sim (ENG-023) opened on a preset or annotation for Control theory — `extends specs/sims/Control_system.json` as `specs/variants/Control_theory.json` · id:ENG-168 · prio:B · type:variant · rev:1373944568 · section:23 (Control system) - [ ] [[PID_controller]] — three · variant of ENG-023 · `u = Kp e + Ki int e + Kd de/dt` · the Control system sim (ENG-023) opened on a preset or annotation for PID controller — `extends specs/sims/Control_system.json` as `specs/variants/PID_controller.json` · id:ENG-169 · prio:B · type:variant · rev:1375289373 · section:23 (Control system) - [ ] [[Feedback]] — three · variant of ENG-023 · `u = Kp e + Ki int e + Kd de/dt` · the Control system sim (ENG-023) opened on a preset or annotation for Feedback — `extends specs/sims/Control_system.json` as `specs/variants/Feedback.json` · id:ENG-170 · prio:B · type:variant · rev:1368412534 · section:23 (Control system) - [ ] [[Servomechanism]] — three · variant of ENG-023 · `u = Kp e + Ki int e + Kd de/dt` · the Control system sim (ENG-023) opened on a preset or annotation for Servomechanism — `extends specs/sims/Control_system.json` as `specs/variants/Servomechanism.json` · id:ENG-171 · prio:B · type:variant · rev:1358730157 · section:23 (Control system) - [ ] [[Mesh_generation]] — three · variant of ENG-024 · `K u = f` · the Finite element method sim (ENG-024) opened on a preset or annotation for Mesh generation — `extends specs/sims/Finite_element_method.json` as `specs/variants/Mesh_generation.json` · id:ENG-172 · prio:B · type:variant · rev:1348218866 · section:24 (Finite element method) - [ ] [[Structural_analysis]] — three · variant of ENG-024 · `K u = f` · the Finite element method sim (ENG-024) opened on a preset or annotation for Structural analysis — `extends specs/sims/Finite_element_method.json` as `specs/variants/Structural_analysis.json` · id:ENG-173 · prio:B · type:variant · rev:1352696427 · section:24 (Finite element method) - [ ] [[Computational_mechanics]] — three · variant of ENG-024 · `K u = f` · the Finite element method sim (ENG-024) opened on a preset or annotation for Computational mechanics — `extends specs/sims/Finite_element_method.json` as `specs/variants/Computational_mechanics.json` · id:ENG-174 · prio:B · type:variant · rev:1373953718 · section:24 (Finite element method) - [ ] [[Failure_rate]] — three · variant of ENG-025 · `R(t) = exp(-lambda t)` · the Reliability engineering sim (ENG-025) opened on a preset or annotation for Failure rate — `extends specs/sims/Reliability_engineering.json` as `specs/variants/Failure_rate.json` · id:ENG-175 · prio:B · type:variant · rev:1369999026 · section:25 (Reliability engineering) - [ ] [[Mean_time_between_failures]] — three · variant of ENG-025 · `R(t) = exp(-lambda t)` · the Reliability engineering sim (ENG-025) opened on a preset or annotation for Mean time between failures — `extends specs/sims/Reliability_engineering.json` as `specs/variants/Mean_time_between_failures.json` · id:ENG-176 · prio:B · type:variant · rev:1365344539 · section:25 (Reliability engineering) - [ ] [[Redundancy_(engineering)]] — three · variant of ENG-025 · `R(t) = exp(-lambda t)` · the Reliability engineering sim (ENG-025) opened on a preset or annotation for Redundancy (engineering) — `extends specs/sims/Reliability_engineering.json` as `specs/variants/Redundancy_(engineering).json` · id:ENG-177 · prio:B · type:variant · rev:1368420639 · section:25 (Reliability engineering) - [ ] [[Requirement]] — three · variant of ENG-026 · `mass, power, cost, risk` · the Systems engineering sim (ENG-026) opened on a preset or annotation for Requirement — `extends specs/sims/Systems_engineering.json` as `specs/variants/Requirement.json` · id:ENG-178 · prio:B · type:variant · rev:1361141061 · section:26 (Systems engineering) - [ ] [[Verification_and_validation]] — three · variant of ENG-026 · `mass, power, cost, risk` · the Systems engineering sim (ENG-026) opened on a preset or annotation for Verification and validation — `extends specs/sims/Systems_engineering.json` as `specs/variants/Verification_and_validation.json` · id:ENG-179 · prio:B · type:variant · rev:1362535329 · section:26 (Systems engineering) - [ ] [[Trade_study]] — three · variant of ENG-026 · `mass, power, cost, risk` · the Systems engineering sim (ENG-026) opened on a preset or annotation for Trade study — `extends specs/sims/Systems_engineering.json` as `specs/variants/Trade_study.json` · id:ENG-180 · prio:B · type:variant · rev:1368945584 · section:26 (Systems engineering) - [ ] [[Industrial_robot]] — three · reuse of MFG-022 · `x = f(theta)` · owned by PORTAL_Manufacturing as row MFG-022 — `manufacturing/Industrial_robot.html` (PORTAL_Manufacturing's section sim, in its queue); this portal adds membership only · id:ENG-181 · prio:B · type:reuse · rev:1376108896 · section:27 (Robotics) - [ ] [[Autonomous_robot]] — three · variant of ENG-027 · `x = f(theta)` · the Robotics sim (ENG-027) opened on a preset or annotation for Autonomous robot — `extends specs/sims/Robotics.json` as `specs/variants/Autonomous_robot.json` · id:ENG-182 · prio:B · type:variant · rev:1373000909 · section:27 (Robotics) - [ ] [[Teleoperation]] — three · variant of ENG-027 · `x = f(theta)` · the Robotics sim (ENG-027) opened on a preset or annotation for Teleoperation — `extends specs/sims/Robotics.json` as `specs/variants/Teleoperation.json` · id:ENG-183 · prio:B · type:variant · rev:1355792680 · section:27 (Robotics) - [ ] [[Robot_kinematics]] — three · variant of ENG-027 · `x = f(theta)` · the Robotics sim (ENG-027) opened on a preset or annotation for Robot kinematics — `extends specs/sims/Robotics.json` as `specs/variants/Robot_kinematics.json` · id:ENG-184 · prio:B · type:variant · rev:1341546050 · section:27 (Robotics) - [ ] [[Mining]] — three · reuse of SMM-011 · `cost per ton` · owned by the apex spine as SMM-011 (Main article); this portal adds membership only · id:ENG-185 · prio:B · type:reuse · rev:1375793834 · section:28 (Mining engineering) - [ ] [[Rock_mechanics]] — three · reuse of SMM-015 · `cost per ton` · owned by the apex spine as SMM-015 (Main article); this portal adds membership only · id:ENG-186 · prio:B · type:reuse · rev:1346482975 · section:28 (Mining engineering) - [ ] [[Mineral_processing]] — three · reuse of SMM-017 · `cost per ton` · owned by the apex spine as SMM-017 (Main article); this portal adds membership only · id:ENG-187 · prio:B · type:reuse · rev:1373534988 · section:28 (Mining engineering) - [ ] [[Rankine's_theory]] — three · variant of ENG-029 · `K_p = (1 + sin phi)/(1 - sin phi)` · the William John Macquorn Rankine sim (ENG-029) opened on a preset or annotation for Rankine's theory — `extends specs/sims/W._J._M._Rankine.json` as `specs/variants/Rankine's_theory.json` · id:ENG-188 · prio:B · type:variant · rev:1361307728 · section:29 (William John Macquorn Rankine) - [ ] [[Lateral_earth_pressure]] — three · variant of ENG-029 · `K_p = (1 + sin phi)/(1 - sin phi)` · the William John Macquorn Rankine sim (ENG-029) opened on a preset or annotation for Lateral earth pressure — `extends specs/sims/W._J._M._Rankine.json` as `specs/variants/Lateral_earth_pressure.json` · id:ENG-189 · prio:B · type:variant · rev:1345469329 · section:29 (William John Macquorn Rankine) - [ ] [[Rankine_cycle]] — three · variant of ENG-029 · `K_p = (1 + sin phi)/(1 - sin phi)` · the William John Macquorn Rankine sim (ENG-029) opened on a preset or annotation for Rankine cycle — `extends specs/sims/W._J._M._Rankine.json` as `specs/variants/Rankine_cycle.json` · id:ENG-190 · prio:B · type:variant · rev:1360731359 · section:29 (William John Macquorn Rankine) - [ ] [[De_architectura]] — three · variant of ENG-030 · `MA = d_in / d_out` · the Vitruvius sim (ENG-030) opened on a preset or annotation for De architectura — `extends specs/sims/Vitruvius.json` as `specs/variants/De_architectura.json` · id:ENG-191 · prio:B · type:variant · rev:1355930312 · section:30 (Vitruvius) - [ ] [[Ancient_Roman_engineering]] — three · variant of ENG-030 · `MA = d_in / d_out` · the Vitruvius sim (ENG-030) opened on a preset or annotation for Ancient Roman engineering — `extends specs/sims/Vitruvius.json` as `specs/variants/Ancient_Roman_engineering.json` · id:ENG-192 · prio:B · type:variant · rev:1374122411 · section:30 (Vitruvius) - [ ] [[Water_wheel]] — three · variant of ENG-030 · `MA = d_in / d_out` · the Vitruvius sim (ENG-030) opened on a preset or annotation for Water wheel — `extends specs/sims/Vitruvius.json` as `specs/variants/Water_wheel.json` · id:ENG-193 · prio:B · type:variant · rev:1375600466 · section:30 (Vitruvius) ## Article Worklist > **Permissions to request up front:** see the block at the head of this page — ask for all of them in one round before the first tool call (browser-pane sites, vault folder, no WT! scope needed here, no deletes, deploy is MTN's). Row grammar: `- [ ] [[Slug]] — action · vault state · rev (bytes) · sim · id · prio · type`. `action` is `mint` (no page in `wiki/` on the 2026-09-22 scan of the vault), `densify` (a page exists below wt-article density: bring it up, append-only), or `place` (a dense page exists, or the article is owned by the apex spine: add this portal's membership and the sim by generator block, no rewrite). Every article follows style guide §2–§6 and §13: slug = the verified Wikipedia title, `oldid` pinned to `rev:`, the H2 skeleton mirrored from that revision, a lead that defines in bold and names the microsim, every figure footnoted to the shelf, a `Wikipedia : Wikitube` section, and a registry row. `WT!` pages sit outside this list. ### Article To Do #### Priority A — Main articles (30) - [ ] [[Stress_(mechanics)]] — place · page exists: 13 H2, 28.6 KB, 1 embed already · rev:1370311866 (45,614 B on Wikipedia) · sim:ENG-001 · id:ENG-A001 · prio:A · type:place · section:1 (Stress) - [ ] [[Hooke's_law]] — place · page exists: 11 H2, 26.2 KB, 1 embed already · rev:1375736650 (57,407 B on Wikipedia) · sim:ENG-002 · id:ENG-A002 · prio:A · type:place · section:2 (Hooke's law) - [ ] [[Compressive_strength]] — mint · no page in wiki/ on 2026-09-22 · rev:1366678192 (29,043 B on Wikipedia) · sim:ENG-003 · id:ENG-A003 · prio:A · type:mint · section:3 (Compressive strength) - [ ] [[Fatigue_(material)]] — place · page exists: 7 H2, 28.6 KB, 2 embeds already · rev:1372946764 (67,152 B on Wikipedia) · sim:ENG-004 · id:ENG-A004 · prio:A · type:place · section:4 (Fatigue) - [ ] [[Beam_(structure)]] — mint · no page in wiki/ on 2026-09-22 · rev:1359179589 (17,738 B on Wikipedia) · sim:ENG-005 · id:ENG-A005 · prio:A · type:mint · section:5 (Beam) - [ ] [[Machine]] — mint · no page in wiki/ on 2026-09-22 · rev:1372733160 (58,612 B on Wikipedia) · sim:ENG-006 · id:ENG-A006 · prio:A · type:mint · section:6 (Machine) - [ ] [[Gear]] — place · page exists: 22 H2, 33.8 KB, 1 embed already · rev:1376154750 (88,939 B on Wikipedia) · sim:ENG-007 · id:ENG-A007 · prio:A · type:place · section:7 (Gear) - [ ] [[Bearing_(mechanical)]] — mint · no page in wiki/ on 2026-09-22 · rev:1366672841 (47,326 B on Wikipedia) · sim:ENG-008 · id:ENG-A008 · prio:A · type:mint · section:8 (Bearing) - [ ] [[Excavator]] — mint · no page in wiki/ on 2026-09-22 · rev:1375580667 (22,784 B on Wikipedia) · sim:ENG-009 · id:ENG-A009 · prio:A · type:mint · section:9 (Excavator) - [ ] [[Conveyor_belt]] — mint · no page in wiki/ on 2026-09-22 · rev:1373776099 (25,364 B on Wikipedia) · sim:ENG-010 · id:ENG-A010 · prio:A · type:mint · section:10 (Conveyor belt) - [ ] [[Electric_motor]] — place · page exists: 10 H2, 57.7 KB, 1 embed already · rev:1374766051 (123,089 B on Wikipedia) · sim:ENG-011 · id:ENG-A011 · prio:A · type:place · section:11 (Electric motor) - [ ] [[Linear_motor]] — mint · no page in wiki/ on 2026-09-22 · rev:1374761198 (29,506 B on Wikipedia) · sim:ENG-012 · id:ENG-A012 · prio:A · type:mint · section:12 (Linear motor) - [ ] [[Solenoid]] — mint · no page in wiki/ on 2026-09-22 · rev:1375710896 (21,651 B on Wikipedia) · sim:ENG-013 · id:ENG-A013 · prio:A · type:mint · section:13 (Solenoid) - [ ] [[Electric_battery]] — place · page exists: 13 H2, 23.4 KB, 1 embed already · rev:1373978617 (67,160 B on Wikipedia) · sim:ENG-014 · id:ENG-A014 · prio:A · type:place · section:14 (Battery) - [ ] [[Hydraulics]] — mint · no page in wiki/ on 2026-09-22 · rev:1367051871 (26,019 B on Wikipedia) · sim:ENG-015 · id:ENG-A015 · prio:A · type:mint · section:15 (Hydraulics) - [ ] [[Radiator]] — mint · no page in wiki/ on 2026-09-22 · rev:1373629056 (10,117 B on Wikipedia) · sim:ENG-016 · id:ENG-A016 · prio:A · type:mint · section:16 (Radiator) - [ ] [[Thermal_insulation]] — mint · no page in wiki/ on 2026-09-22 · rev:1375683766 (17,908 B on Wikipedia) · sim:ENG-017 · id:ENG-A017 · prio:A · type:mint · section:17 (Thermal insulation) - [ ] [[Heat_exchanger]] — mint · no page in wiki/ on 2026-09-22 · rev:1375531639 (81,672 B on Wikipedia) · sim:ENG-018 · id:ENG-A018 · prio:A · type:mint · section:18 (Heat exchanger) - [ ] [[Solar_furnace]] — mint · no page in wiki/ on 2026-09-22 · rev:1311736603 (7,628 B on Wikipedia) · sim:ENG-019 · id:ENG-A019 · prio:A · type:mint · section:19 (Furnace) - [ ] [[Thermal_expansion]] — place · page exists: 14 H2, 21.4 KB, 1 embed already · rev:1368853368 (51,511 B on Wikipedia) · sim:ENG-020 · id:ENG-A020 · prio:A · type:place · section:20 (Thermal expansion) - [ ] [[Engineering_tolerance]] — mint · no page in wiki/ on 2026-09-22 · rev:1315161613 (14,324 B on Wikipedia) · sim:ENG-021 · id:ENG-A021 · prio:A · type:mint · section:21 (Engineering tolerance) - [ ] [[Metrology]] — mint · no page in wiki/ on 2026-09-22 · rev:1373568765 (59,563 B on Wikipedia) · sim:ENG-022 · id:ENG-A022 · prio:A · type:mint · section:22 (Metrology) - [ ] [[Control_system]] — place · page exists: 10 H2, 7.8 KB, no embed · rev:1364618081 (9,124 B on Wikipedia) · sim:ENG-023 · id:ENG-A023 · prio:A · type:place · section:23 (Control system) - [ ] [[Finite_element_method]] — place · page exists: 14 H2, 22.5 KB, 1 embed already · rev:1373533703 (62,143 B on Wikipedia) · sim:ENG-024 · id:ENG-A024 · prio:A · type:place · section:24 (Finite element method) - [ ] [[Reliability_engineering]] — place · page exists: 7 H2, 5.5 KB, no embed · rev:1344593273 (101,150 B on Wikipedia) · sim:ENG-025 · id:ENG-A025 · prio:A · type:place · section:25 (Reliability engineering) - [ ] [[Systems_engineering]] — densify · stub exists: 4 H2, 2.4 KB · rev:1374062683 (57,896 B on Wikipedia) · sim:ENG-026 · id:ENG-A026 · prio:A · type:densify · section:26 (Systems engineering) - [ ] [[Robotics]] — place · page exists: 8 H2, 17.7 KB, no embed · rev:1375005708 (109,144 B on Wikipedia) · sim:ENG-027 · id:ENG-A027 · prio:A · type:place · section:27 (Robotics) - [ ] [[Mining_engineering]] — place · page exists: 9 H2, 12.8 KB, no embed · rev:1368378670 (40,028 B on Wikipedia) · sim:ENG-028 · id:ENG-A028 · prio:A · type:place · section:28 (Mining engineering) - [ ] [[W._J._M._Rankine]] — mint · no page in wiki/ on 2026-09-22 · rev:1372006024 (23,657 B on Wikipedia) · sim:ENG-029 · id:ENG-A029 · prio:A · type:mint · section:29 (William John Macquorn Rankine) - [ ] [[Vitruvius]] — mint · no page in wiki/ on 2026-09-22 · rev:1371786545 (46,335 B on Wikipedia) · sim:ENG-030 · id:ENG-A030 · prio:A · type:mint · section:30 (Vitruvius) #### Priority B — See-also children (93) - [ ] [[Strain_(mechanics)]] — mint · no page in wiki/ on 2026-09-22 · rev:1365996368 (17,784 B on Wikipedia) · sim:ENG-101 · See-also of section 1 (Stress) · id:ENG-A101 · prio:B · type:mint - [ ] [[Shear_stress]] — mint · no page in wiki/ on 2026-09-22 · rev:1343187277 (14,040 B on Wikipedia) · sim:ENG-102 · See-also of section 1 (Stress) · id:ENG-A102 · prio:B · type:mint - [ ] [[Mohr's_circle]] — mint · no page in wiki/ on 2026-09-22 · rev:1330528049 (45,138 B on Wikipedia) · sim:ENG-103 · See-also of section 1 (Stress) · id:ENG-A103 · prio:B · type:mint - [ ] [[Yield_(engineering)]] — mint · no page in wiki/ on 2026-09-22 · rev:1368584646 (22,982 B on Wikipedia) · sim:ENG-104 · See-also of section 1 (Stress) · id:ENG-A104 · prio:B · type:mint - [ ] [[Young's_modulus]] — mint · no page in wiki/ on 2026-09-22 · rev:1368470046 (44,516 B on Wikipedia) · sim:ENG-105 · See-also of section 2 (Hooke's law) · id:ENG-A105 · prio:B · type:mint - [ ] [[Spring_(device)]] — mint · no page in wiki/ on 2026-09-22 · rev:1367387211 (27,032 B on Wikipedia) · sim:ENG-106 · See-also of section 2 (Hooke's law) · id:ENG-A106 · prio:B · type:mint - [ ] [[Stiffness]] — mint · no page in wiki/ on 2026-09-22 · rev:1369105655 (10,911 B on Wikipedia) · sim:ENG-107 · See-also of section 2 (Hooke's law) · id:ENG-A107 · prio:B · type:mint - [ ] [[Ultimate_tensile_strength]] — mint · no page in wiki/ on 2026-09-22 · rev:1356978255 (32,582 B on Wikipedia) · sim:ENG-108 · See-also of section 3 (Compressive strength) · id:ENG-A108 · prio:B · type:mint - [ ] [[Brittleness]] — mint · no page in wiki/ on 2026-09-22 · rev:1348177754 (7,194 B on Wikipedia) · sim:ENG-109 · See-also of section 3 (Compressive strength) · id:ENG-A109 · prio:B · type:mint - [ ] [[Rock_mass_rating]] — mint · no page in wiki/ on 2026-09-22 · rev:1333206116 (10,780 B on Wikipedia) · sim:ENG-110 · See-also of section 3 (Compressive strength) · id:ENG-A110 · prio:B · type:mint - [ ] [[Fracture_mechanics]] — place · page exists: 6 H2, 9.4 KB, 2 embeds already · rev:1362286178 (41,668 B on Wikipedia) · sim:ENG-111 · See-also of section 4 (Fatigue) · id:ENG-A111 · prio:B · type:place - [ ] [[Bending]] — place · page exists: 9 H2, 25.1 KB, 1 embed already · rev:1351473367 (27,430 B on Wikipedia) · sim:ENG-112 · See-also of section 5 (Beam) · id:ENG-A112 · prio:B · type:place - [ ] [[Euler–Bernoulli_beam_theory]] — mint · no page in wiki/ on 2026-09-22 · rev:1373956269 (50,595 B on Wikipedia) · sim:ENG-113 · See-also of section 5 (Beam) · id:ENG-A113 · prio:B · type:mint - [ ] [[Buckling]] — place · page exists: 7 H2, 36.9 KB, 1 embed already · rev:1362996017 (42,235 B on Wikipedia) · sim:ENG-114 · See-also of section 5 (Beam) · id:ENG-A114 · prio:B · type:place - [ ] [[Deflection_(engineering)]] — mint · no page in wiki/ on 2026-09-22 · rev:1315389755 (12,830 B on Wikipedia) · sim:ENG-115 · See-also of section 5 (Beam) · id:ENG-A115 · prio:B · type:mint - [ ] [[Simple_machine]] — place · page exists: 9 H2, 21.9 KB, 1 embed already · rev:1369419169 (34,234 B on Wikipedia) · sim:ENG-116 · See-also of section 6 (Machine) · id:ENG-A116 · prio:B · type:place - [ ] [[Mechanical_advantage]] — mint · no page in wiki/ on 2026-09-22 · rev:1374324181 (19,794 B on Wikipedia) · sim:ENG-117 · See-also of section 6 (Machine) · id:ENG-A117 · prio:B · type:mint - [ ] [[Mechanism_(engineering)]] — mint · no page in wiki/ on 2026-09-22 · rev:1373781083 (19,968 B on Wikipedia) · sim:ENG-118 · See-also of section 6 (Machine) · id:ENG-A118 · prio:B · type:mint - [ ] [[Gear_train]] — mint · no page in wiki/ on 2026-09-22 · rev:1362680818 (33,204 B on Wikipedia) · sim:ENG-119 · See-also of section 7 (Gear) · id:ENG-A119 · prio:B · type:mint - [ ] [[Involute_gear]] — mint · no page in wiki/ on 2026-09-22 · rev:1357422837 (8,603 B on Wikipedia) · sim:ENG-120 · See-also of section 7 (Gear) · id:ENG-A120 · prio:B · type:mint - [ ] [[Torque]] — mint · no page in wiki/ on 2026-09-22 · rev:1373522769 (35,064 B on Wikipedia) · sim:ENG-121 · See-also of section 7 (Gear) · id:ENG-A121 · prio:B · type:mint - [ ] [[Rolling-element_bearing]] — mint · no page in wiki/ on 2026-09-22 · rev:1361059116 (38,869 B on Wikipedia) · sim:ENG-122 · See-also of section 8 (Bearing) · id:ENG-A122 · prio:B · type:mint - [ ] [[Plain_bearing]] — mint · no page in wiki/ on 2026-09-22 · rev:1370581706 (37,383 B on Wikipedia) · sim:ENG-123 · See-also of section 8 (Bearing) · id:ENG-A123 · prio:B · type:mint - [ ] [[Lubrication]] — mint · no page in wiki/ on 2026-09-22 · rev:1368801522 (9,669 B on Wikipedia) · sim:ENG-124 · See-also of section 8 (Bearing) · id:ENG-A124 · prio:B · type:mint - [ ] [[Tribology]] — place · page exists: 10 H2, 6.9 KB, no embed · rev:1373312982 (64,313 B on Wikipedia) · sim:ENG-125 · See-also of section 8 (Bearing) · id:ENG-A125 · prio:B · type:place - [ ] [[Bucket-wheel_excavator]] — mint · no page in wiki/ on 2026-09-22 · rev:1375073893 (13,690 B on Wikipedia) · sim:ENG-126 · See-also of section 9 (Excavator) · id:ENG-A126 · prio:B · type:mint - [ ] [[Dragline_excavator]] — mint · no page in wiki/ on 2026-09-22 · rev:1353631617 (22,382 B on Wikipedia) · sim:ENG-127 · See-also of section 9 (Excavator) · id:ENG-A127 · prio:B · type:mint - [ ] [[Loader_(equipment)]] — mint · no page in wiki/ on 2026-09-22 · rev:1361997893 (20,937 B on Wikipedia) · sim:ENG-128 · See-also of section 9 (Excavator) · id:ENG-A128 · prio:B · type:mint - [ ] [[Bulk_material_handling]] — mint · no page in wiki/ on 2026-09-22 · rev:1275024064 (3,988 B on Wikipedia) · sim:ENG-129 · See-also of section 10 (Conveyor belt) · id:ENG-A129 · prio:B · type:mint - [ ] [[Screw_conveyor]] — mint · no page in wiki/ on 2026-09-22 · rev:1360734827 (13,495 B on Wikipedia) · sim:ENG-130 · See-also of section 10 (Conveyor belt) · id:ENG-A130 · prio:B · type:mint - [ ] [[Bucket_elevator]] — mint · no page in wiki/ on 2026-09-22 · rev:1325712395 (4,422 B on Wikipedia) · sim:ENG-131 · See-also of section 10 (Conveyor belt) · id:ENG-A131 · prio:B · type:mint - [ ] [[Brushless_DC_electric_motor]] — mint · no page in wiki/ on 2026-09-22 · rev:1375439361 (32,751 B on Wikipedia) · sim:ENG-132 · See-also of section 11 (Electric motor) · id:ENG-A132 · prio:B · type:mint - [ ] [[Efficiency]] — mint · no page in wiki/ on 2026-09-22 · rev:1365456617 (12,212 B on Wikipedia) · sim:ENG-133 · See-also of section 11 (Electric motor) · id:ENG-A133 · prio:B · type:mint - [ ] [[Coilgun]] — mint · no page in wiki/ on 2026-09-22 · rev:1354179401 (35,077 B on Wikipedia) · sim:ENG-134 · See-also of section 12 (Linear motor) · id:ENG-A134 · prio:B · type:mint - [ ] [[Railgun]] — mint · no page in wiki/ on 2026-09-22 · rev:1376205319 (110,381 B on Wikipedia) · sim:ENG-135 · See-also of section 12 (Linear motor) · id:ENG-A135 · prio:B · type:mint - [ ] [[Maglev]] — mint · no page in wiki/ on 2026-09-22 · rev:1375450083 (152,036 B on Wikipedia) · sim:ENG-136 · See-also of section 12 (Linear motor) · id:ENG-A136 · prio:B · type:mint - [ ] [[Inductor]] — place · page exists: 12 H2, 11.6 KB, 1 embed already · rev:1375788705 (66,250 B on Wikipedia) · sim:ENG-137 · See-also of section 13 (Solenoid) · id:ENG-A137 · prio:B · type:place - [ ] [[Inductance]] — mint · no page in wiki/ on 2026-09-22 · rev:1372308482 (61,898 B on Wikipedia) · sim:ENG-138 · See-also of section 13 (Solenoid) · id:ENG-A138 · prio:B · type:mint - [ ] [[Magnetic_flux]] — mint · no page in wiki/ on 2026-09-22 · rev:1367678492 (10,396 B on Wikipedia) · sim:ENG-139 · See-also of section 13 (Solenoid) · id:ENG-A139 · prio:B · type:mint - [ ] [[Lithium-ion_battery]] — place · page exists: 16 H2, 23.1 KB, 1 embed already · rev:1375830392 (162,770 B on Wikipedia) · sim:ENG-140 · See-also of section 14 (Battery) · id:ENG-A140 · prio:B · type:place - [ ] [[Energy_density]] — mint · no page in wiki/ on 2026-09-22 · rev:1366889538 (69,566 B on Wikipedia) · sim:ENG-141 · See-also of section 14 (Battery) · id:ENG-A141 · prio:B · type:mint - [ ] [[Specific_energy]] — mint · no page in wiki/ on 2026-09-22 · rev:1325119006 (10,996 B on Wikipedia) · sim:ENG-142 · See-also of section 14 (Battery) · id:ENG-A142 · prio:B · type:mint - [ ] [[Hydraulic_cylinder]] — mint · no page in wiki/ on 2026-09-22 · rev:1373421738 (27,690 B on Wikipedia) · sim:ENG-143 · See-also of section 15 (Hydraulics) · id:ENG-A143 · prio:B · type:mint - [ ] [[Pascal's_law]] — mint · no page in wiki/ on 2026-09-22 · rev:1363145553 (10,844 B on Wikipedia) · sim:ENG-144 · See-also of section 15 (Hydraulics) · id:ENG-A144 · prio:B · type:mint - [ ] [[Hydraulic_machinery]] — mint · no page in wiki/ on 2026-09-22 · rev:1374318756 (34,458 B on Wikipedia) · sim:ENG-145 · See-also of section 15 (Hydraulics) · id:ENG-A145 · prio:B · type:mint - [ ] [[Spacecraft_thermal_control]] — mint · owned by the apex spine (SMM-027: mint) · rev:1344666664 (28,603 B on Wikipedia) · sim:ENG-146 · See-also of section 16 (Radiator) · id:ENG-A146 · prio:B · type:mint - [ ] [[Heat_pipe]] — mint · no page in wiki/ on 2026-09-22 · rev:1368764634 (59,418 B on Wikipedia) · sim:ENG-147 · See-also of section 16 (Radiator) · id:ENG-A147 · prio:B · type:mint - [ ] [[Radiator_(engine_cooling)]] — mint · no page in wiki/ on 2026-09-22 · rev:1375606111 (27,572 B on Wikipedia) · sim:ENG-148 · See-also of section 16 (Radiator) · id:ENG-A148 · prio:B · type:mint - [ ] [[Multi-layer_insulation]] — mint · no page in wiki/ on 2026-09-22 · rev:1373023315 (12,788 B on Wikipedia) · sim:ENG-149 · See-also of section 17 (Thermal insulation) · id:ENG-A149 · prio:B · type:mint - [ ] [[Thermal_conductivity_and_resistivity]] — place · page exists: 13 H2, 24.4 KB, 1 embed already · rev:1374231229 (66,840 B on Wikipedia) · sim:ENG-150 · See-also of section 17 (Thermal insulation) · id:ENG-A150 · prio:B · type:place - [ ] [[R-value_(insulation)]] — mint · no page in wiki/ on 2026-09-22 · rev:1375683636 (62,202 B on Wikipedia) · sim:ENG-151 · See-also of section 17 (Thermal insulation) · id:ENG-A151 · prio:B · type:mint - [ ] [[Countercurrent_exchange]] — mint · no page in wiki/ on 2026-09-22 · rev:1365558993 (39,833 B on Wikipedia) · sim:ENG-152 · See-also of section 18 (Heat exchanger) · id:ENG-A152 · prio:B · type:mint - [ ] [[Logarithmic_mean_temperature_difference]] — mint · no page in wiki/ on 2026-09-22 · rev:1369555987 (7,406 B on Wikipedia) · sim:ENG-153 · See-also of section 18 (Heat exchanger) · id:ENG-A153 · prio:B · type:mint - [ ] [[Heat_recovery_ventilation]] — mint · no page in wiki/ on 2026-09-22 · rev:1369528708 (45,568 B on Wikipedia) · sim:ENG-154 · See-also of section 18 (Heat exchanger) · id:ENG-A154 · prio:B · type:mint - [ ] [[Induction_heating]] — mint · no page in wiki/ on 2026-09-22 · rev:1364504193 (16,356 B on Wikipedia) · sim:ENG-155 · See-also of section 19 (Furnace) · id:ENG-A155 · prio:B · type:mint - [ ] [[Electric_arc_furnace]] — mint · no page in wiki/ on 2026-09-22 · rev:1359507483 (37,367 B on Wikipedia) · sim:ENG-156 · See-also of section 19 (Furnace) · id:ENG-A156 · prio:B · type:mint - [ ] [[Kiln]] — mint · no page in wiki/ on 2026-09-22 · rev:1373821245 (26,714 B on Wikipedia) · sim:ENG-157 · See-also of section 19 (Furnace) · id:ENG-A157 · prio:B · type:mint - [ ] [[Thermal_stress]] — mint · no page in wiki/ on 2026-09-22 · rev:1328627048 (4,583 B on Wikipedia) · sim:ENG-158 · See-also of section 20 (Thermal expansion) · id:ENG-A158 · prio:B · type:mint - [ ] [[Bimetallic_strip]] — mint · no page in wiki/ on 2026-09-22 · rev:1367990031 (14,410 B on Wikipedia) · sim:ENG-159 · See-also of section 20 (Thermal expansion) · id:ENG-A159 · prio:B · type:mint - [ ] [[Tolerance_analysis]] — mint · no page in wiki/ on 2026-09-22 · rev:1347049327 (9,847 B on Wikipedia) · sim:ENG-160 · See-also of section 21 (Engineering tolerance) · id:ENG-A160 · prio:B · type:mint - [ ] [[Interchangeable_parts]] — mint · no page in wiki/ on 2026-09-22 · rev:1364850391 (26,904 B on Wikipedia) · sim:ENG-161 · See-also of section 21 (Engineering tolerance) · id:ENG-A161 · prio:B · type:mint - [ ] [[Engineering_fit]] — mint · no page in wiki/ on 2026-09-22 · rev:1338122685 (17,803 B on Wikipedia) · sim:ENG-162 · See-also of section 21 (Engineering tolerance) · id:ENG-A162 · prio:B · type:mint - [ ] [[Geometric_dimensioning_and_tolerancing]] — mint · no page in wiki/ on 2026-09-22 · rev:1362286596 (31,674 B on Wikipedia) · sim:ENG-163 · See-also of section 21 (Engineering tolerance) · id:ENG-A163 · prio:B · type:mint - [ ] [[Coordinate-measuring_machine]] — mint · no page in wiki/ on 2026-09-22 · rev:1333129344 (19,557 B on Wikipedia) · sim:ENG-164 · See-also of section 22 (Metrology) · id:ENG-A164 · prio:B · type:mint - [ ] [[Calibration]] — mint · no page in wiki/ on 2026-09-22 · rev:1355776629 (31,674 B on Wikipedia) · sim:ENG-165 · See-also of section 22 (Metrology) · id:ENG-A165 · prio:B · type:mint - [ ] [[Gauge_block]] — mint · no page in wiki/ on 2026-09-22 · rev:1367013863 (25,056 B on Wikipedia) · sim:ENG-166 · See-also of section 22 (Metrology) · id:ENG-A166 · prio:B · type:mint - [ ] [[Measurement_uncertainty]] — mint · no page in wiki/ on 2026-09-22 · rev:1367370535 (28,386 B on Wikipedia) · sim:ENG-167 · See-also of section 22 (Metrology) · id:ENG-A167 · prio:B · type:mint - [ ] [[Control_theory]] — place · page exists: 7 H2, 6.8 KB, no embed · rev:1373944568 (45,844 B on Wikipedia) · sim:ENG-168 · See-also of section 23 (Control system) · id:ENG-A168 · prio:B · type:place - [ ] [[PID_controller]] — place · page exists: 12 H2, 8.8 KB, no embed · rev:1375289373 (86,498 B on Wikipedia) · sim:ENG-169 · See-also of section 23 (Control system) · id:ENG-A169 · prio:B · type:place - [ ] [[Feedback]] — place · page exists: 8 H2, 6.0 KB, no embed · rev:1368412534 (51,773 B on Wikipedia) · sim:ENG-170 · See-also of section 23 (Control system) · id:ENG-A170 · prio:B · type:place - [ ] [[Servomechanism]] — mint · no page in wiki/ on 2026-09-22 · rev:1358730157 (14,073 B on Wikipedia) · sim:ENG-171 · See-also of section 23 (Control system) · id:ENG-A171 · prio:B · type:mint - [ ] [[Mesh_generation]] — mint · no page in wiki/ on 2026-09-22 · rev:1348218866 (48,502 B on Wikipedia) · sim:ENG-172 · See-also of section 24 (Finite element method) · id:ENG-A172 · prio:B · type:mint - [ ] [[Structural_analysis]] — mint · no page in wiki/ on 2026-09-22 · rev:1352696427 (19,052 B on Wikipedia) · sim:ENG-173 · See-also of section 24 (Finite element method) · id:ENG-A173 · prio:B · type:mint - [ ] [[Computational_mechanics]] — mint · no page in wiki/ on 2026-09-22 · rev:1373953718 (5,764 B on Wikipedia) · sim:ENG-174 · See-also of section 24 (Finite element method) · id:ENG-A174 · prio:B · type:mint - [ ] [[Failure_rate]] — mint · no page in wiki/ on 2026-09-22 · rev:1369999026 (25,353 B on Wikipedia) · sim:ENG-175 · See-also of section 25 (Reliability engineering) · id:ENG-A175 · prio:B · type:mint - [ ] [[Mean_time_between_failures]] — mint · no page in wiki/ on 2026-09-22 · rev:1365344539 (19,857 B on Wikipedia) · sim:ENG-176 · See-also of section 25 (Reliability engineering) · id:ENG-A176 · prio:B · type:mint - [ ] [[Redundancy_(engineering)]] — place · page exists: 8 H2, 35.8 KB, no embed · rev:1368420639 (20,660 B on Wikipedia) · sim:ENG-177 · See-also of section 25 (Reliability engineering) · id:ENG-A177 · prio:B · type:place - [ ] [[Requirement]] — mint · no page in wiki/ on 2026-09-22 · rev:1361141061 (24,639 B on Wikipedia) · sim:ENG-178 · See-also of section 26 (Systems engineering) · id:ENG-A178 · prio:B · type:mint - [ ] [[Verification_and_validation]] — mint · no page in wiki/ on 2026-09-22 · rev:1362535329 (54,746 B on Wikipedia) · sim:ENG-179 · See-also of section 26 (Systems engineering) · id:ENG-A179 · prio:B · type:mint - [ ] [[Trade_study]] — mint · no page in wiki/ on 2026-09-22 · rev:1368945584 (3,611 B on Wikipedia) · sim:ENG-180 · See-also of section 26 (Systems engineering) · id:ENG-A180 · prio:B · type:mint - [ ] [[Industrial_robot]] — mint · no page in wiki/ on 2026-09-22 · rev:1376108896 (46,503 B on Wikipedia) · sim:ENG-181 · See-also of section 27 (Robotics) · id:ENG-A181 · prio:B · type:mint - [ ] [[Autonomous_robot]] — mint · no page in wiki/ on 2026-09-22 · rev:1373000909 (47,778 B on Wikipedia) · sim:ENG-182 · See-also of section 27 (Robotics) · id:ENG-A182 · prio:B · type:mint - [ ] [[Teleoperation]] — mint · no page in wiki/ on 2026-09-22 · rev:1355792680 (7,322 B on Wikipedia) · sim:ENG-183 · See-also of section 27 (Robotics) · id:ENG-A183 · prio:B · type:mint - [ ] [[Robot_kinematics]] — mint · no page in wiki/ on 2026-09-22 · rev:1341546050 (6,342 B on Wikipedia) · sim:ENG-184 · See-also of section 27 (Robotics) · id:ENG-A184 · prio:B · type:mint - [ ] [[Mining]] — mint · owned by the apex spine (SMM-011: mint) · rev:1375793834 (149,481 B on Wikipedia) · sim:ENG-185 · See-also of section 28 (Mining engineering) · id:ENG-A185 · prio:B · type:mint - [ ] [[Rock_mechanics]] — mint · owned by the apex spine (SMM-015: mint) · rev:1346482975 (7,847 B on Wikipedia) · sim:ENG-186 · See-also of section 28 (Mining engineering) · id:ENG-A186 · prio:B · type:mint - [ ] [[Mineral_processing]] — mint · owned by the apex spine (SMM-017: mint) · rev:1373534988 (40,595 B on Wikipedia) · sim:ENG-187 · See-also of section 28 (Mining engineering) · id:ENG-A187 · prio:B · type:mint - [ ] [[Rankine's_theory]] — mint · no page in wiki/ on 2026-09-22 · rev:1361307728 (4,340 B on Wikipedia) · sim:ENG-188 · See-also of section 29 (William John Macquorn Rankine) · id:ENG-A188 · prio:B · type:mint - [ ] [[Lateral_earth_pressure]] — mint · no page in wiki/ on 2026-09-22 · rev:1345469329 (34,832 B on Wikipedia) · sim:ENG-189 · See-also of section 29 (William John Macquorn Rankine) · id:ENG-A189 · prio:B · type:mint - [ ] [[Rankine_cycle]] — place · page exists: 12 H2, 21.0 KB, 1 embed already · rev:1360731359 (19,131 B on Wikipedia) · sim:ENG-190 · See-also of section 29 (William John Macquorn Rankine) · id:ENG-A190 · prio:B · type:place - [ ] [[De_architectura]] — mint · no page in wiki/ on 2026-09-22 · rev:1355930312 (30,201 B on Wikipedia) · sim:ENG-191 · See-also of section 30 (Vitruvius) · id:ENG-A191 · prio:B · type:mint - [ ] [[Ancient_Roman_engineering]] — mint · no page in wiki/ on 2026-09-22 · rev:1374122411 (19,956 B on Wikipedia) · sim:ENG-192 · See-also of section 30 (Vitruvius) · id:ENG-A192 · prio:B · type:mint - [ ] [[Water_wheel]] — place · page exists: 12 H2, 10.3 KB, no embed · rev:1375600466 (84,676 B on Wikipedia) · sim:ENG-193 · See-also of section 30 (Vitruvius) · id:ENG-A193 · prio:B · type:place *Generated 2026-09-22 by `build_portals9.py` (Space Mining Pt 1, item 9) from `jobs.json`; 124 microsim rows (1 hero + 30 section + 93 variant) · 123 article rows · 0 deletions. Do not hand-edit inside this region; rerun the builder or use `wtq.py` on the shard.*  --- *In-service block appended 2026-09-22 (Space Mining Pt 1 run, item 9) · append-only · 0 deletions · the page's own spine, gallery and blocks above are untouched*