Theory 038/Robotics & Autonomy
Soft Actuators Are a Pressure Ratio
The claim
Soft actuator stroke is set by the ratio of chamber pressure to wall stiffness rather than by pressure alone, so a stiffer body can deliver less motion at higher pressure.
01The mechanism
Inflation competes with wall deformation; the ratio sets how much energy goes into bending versus stretching.
02Predictions
- P1Stroke should collapse onto the ratio.
- P2Stiffer walls should reduce stroke at fixed pressure.
03Refutation
Stroke tracking pressure at fixed stiffness would remove the ratio.