Textile-based Soft Wearable Robots for Upper-Limb Rehabilitation and Assistance

Abstract

Soft-wearable robots for the upper-limb have been developed in recent years for both rehabilitative and assistive purposes. Soft wearable robots are of particular interest due to their inherent compliance and lightweight nature. However they face several challenges in effectively delivering assistance to the target joints, a lack of intuitive control, and sparse on-body evaluations for target populations. This dissertation details my contributions to the field of soft wearable upper-limb robots, in particular to address several of these challenges. To start, unfolding textile-based pneumatic actuators were developed to deliver the torques directly to the target joint, and the actuation mechanisms of the actuators were modelled and validated using an array of physical prototypes. The control of these actuators was then improved through the development of a low-level fluidic controller to enable high-bandwidth pressure modulation of the actuators. These advancements in low-level control enabled the implementation of various high level control strategies, in particular gravity compensation of the upper-limbs. The robot developed during this thesis intuitively responds to the wearer’s motions and provides the gross motive force to compensate for the effects of gravity on the limb, thus allowing the wearer to focus primarily on fine motor functions. Finally, this thesis includes several on-body evaluations to determine the biomechanical and physiological effects of soft wearable robots on healthy and clinical populations. This includes evaluation on stroke survivors and individuals with ALS, both who experienced significant improvements in their functional range of motion and ability to perform activities of daily living when wearing a soft wearable robot. Overall these on-body evaluations also improved our understanding of the challenges of effectively anchoring these textile-based actuators to the body, particularly with clinical populations. The thesis seeks to address some of the current challenges facing soft wearable robots for the upper limb; and forms a foundation for the creation of more advanced and capable soft wearable robots for use by clinical populations in the near future.