Pulleys with Tightening Mechanism
Resembles 1, with the addition of a movable tightening pulley, B. When this pulley is pressed against the band to take up the slack, the belt transmits motion from one of the larger pulleys to the other; but when it is not, the belt is so slack as not to transmit motion.
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
- belt (friction; 100-link elastic chain, 4 N) + tightening pulley B on a sprung handle, wrapping the back of the slack side
- Measured
- B in → ω_bot/ω_top 1.425 (0.1% creep); B withdrawn at 4 s → 0.001 (top pulley still at speed); B in again at 8 s → 1.410; withdrawn from start → |ω_bot| 0.002 rad/s; μ≈0 control 0.000; pen ≤1.25 mm
- Notes
- Only the top pulley is motor-driven. The operator's hand moves only B's spring (`hand:` schedule), shown in the render.
Film (MP4) · GIF · Still (PNG) · Spec (YAML) · Model (MJCF)
