A Textile-Based Pneumatic Soft Suit for Elbow Joint Rehabilitation

Abstract

Stroke is a disease with a very high mortality rate, and most patients will experience upper limb dysfunction after the disease. Traditional solutions, commonly rigid exoskeletons, have been explored extensively but often fall short due to safety concerns, discomfort, and potential for skin damage owing to their hard attachment mechanisms. To overcome these limitations, this article proposes a textile pneumatic soft suit for elbow joint rehabilitation. This soft suit consists of a modular pneumatic actuator that can help patients with elbow joint flexion and extension rehabilitation training. The design principle is based on the deformation of the textile-based pneumatic bag. The actuator is made of flexible fabric sheets of woven nylon with thermoplastic polyurethane (TPU) coating and 3D printing technology. A mathematical model was developed to describe the relationship between flexion angle and cable length, which could guide the design of the actuator. Experimental validation involved both static and dynamic assessments, confirming the soft suit's capability to meet the requirements of torque and range of the motions. The actuator can provide a starting torque of 7.18 Nm under a pressure of 160 kPa. The suit can provide a range of flexion motion of over 100° for a 1650 g forearm. In the future, we will conduct modeling and further experimental verification of the robot system to complete its control.