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Creative Workshop

Joint Actuator Anatomy Lab

Humanoid joint module · switch planetary, harmonic or cycloidal drive · 18/18/54T · 3 planets · 4:1

Motor1,200 rpm
Output300 rpm
Ratio4:1
Slow-mo91×
Torque gain×4
Turning

Gearbox

Sun in · ring fixed · carrier out

View

The whole joint module: electrics, motor, gear train, output and fasteners.

Explode

55%

Push the parts apart along the axis; 0 is assembled, 1 is fully exploded

Drive demo

1,200 rpm

Motor speed before reduction. The scene renders in slow motion — at 3000 rpm the teeth are a blur

Reduction
4:1
Output speed
300 rpm
Planet spin
-600 rpm
Torque gain
×4
η / backdrive
97% · yes

Rendered in slow motion: real speed ÷ slow-motion factor is what you see on screen

Camera

Parts

16 parts, listed in assembly order from the rear forward. Click one to highlight it and pull up its note.

Click a part in the scene, or pick one below, and its job plus one engineering fact show up here.

How this module is computed

Highest efficiency, back-drivable and shock tolerant: impacts pass through the gearbox to the motor, which is why QDD joints can afford dynamic motion. The price is 3–10:1 per stage, so a slow, strong joint has to buy speed from the motor.

Every part is generated procedurally — no CAD model is loaded. This is a representative joint module, not a scan of any one product. The teeth are stylised rather than involute, but the ratio comes from the analytic solution, so what meshes on screen and what the readouts say are always the same thing. All three gearboxes share the motor and output; only the four drivetrain parts change.