“Multiple gearing”—a recent invention
“Multiple gearing”—a recent invention. The smaller triangular wheel drives the larger one by the movement of its attached friction-rollers in the radial grooves.
Only the input is driven; every other part of this model moves by physics (MuJoCo), and its ratios are measured. Run it live, change its parameters, or switch the friction off to see the output stop.
- Modelled as
- triangular driver with three pin-mounted friction-rollers, on a shaft 4 cm from the wheel's centre (Cardan 3:6: pins at r 4, six parallel radial grooves half-width 0.72 open through to a central hole)
- Measured
- wheel/driver 0.5000 vs the internal-gear count 3/6 = 1/2, window 3 whole driver turns (ripple ±1.6%, wheel 1.53–1.58 rad/s, driver 3.09/π rad/s), wheel never runs back, pen ≤ 0.02 mm
- Notes
- Only the driver's crank is driven (velocity, 30 rpm). Drive is roller-on-groove-flank contact only; at rest all three rollers stand dead-centre in their grooves. Negative control: rollers' contact switched off → the wheel stays perfectly still (spin −0.0000, no drift).
Film (MP4) · GIF · Still (PNG) · Spec (YAML) · Model (MJCF)
