A Soft Robotic Module with Pneumatic Actuation and Enhanced Controllability Using a Shape Memory Alloy Wire

The paper presents a soft robotic bending module driven by compressed air. To improve how accurately it can bend, the authors incorporate a shape memory alloy (SMA) wire into the module. They first fabricate a fiber-reinforced bending module with a strain-limiting layer made of polypropylene. They then replace that strain-limiting layer with a silicon matrix that holds the SMA wire, aiming to better regulate bending behavior. A simple closed-loop control algorithm uses camera measurements of the bending angle in the vertical plane. Experiments test bending angles from 0 to 65 degrees and show that the SMA wire improves control precision and speed, reducing angle error and rise time while also allowing more bending with less working pressure.