Design of soft exosuit for elbow assistance using butyl rubber tubes and textile

Abstract

Soft materials show numerous advantages compared to rigid ones in exosuit devices. We present the design of a soft wearable elbow assistance device with flexion and extension actuations. Commercially available butyl rubber tubes have been used as a pneumatic actuator. Tubes are enveloped by a lightweight polyester fabric to eliminate a non-homogeneous expansion. The surrounding fabric in turn is mounted on a clothes fabric as zigzag paths. The exosuit is lightweight, shock resistant, simple to manufacture, and low cost. The subjective experiments show a reduction average of 48% in the Rectified & integrated raw electromyography signal of the brachialis muscle during a rhythmic flexion/extension sequence while lifting weights (3 and 5 [kg]). Results indicate a significant assistance with respect to the other existing soft elbow exosuits.