(A) wearable wrist-forearm rehabilitation orthosis using tendon driven mechanism

Abstract

Due to neurological diseases, more than 50 million people live with persistent upper limb impairments worldwide, and 40% of patients remain impaired even after intensive hospital care. Robot-assisted rehabilitation has seen growing interest in the last decades to help patients getting out of this predicament. In a series of activities of daily living (ADL) related to upper limb movement, the key role played by the forearm and wrist is often overlooked. There are few studies on wearable rehabilitation devices for forearm pronation/supination movement, since the coincidence of the rotation axis with the forearm presents design challenges. Also, due to the global pandemic of COVID-19, many stroke patients have difficulty or no access to specific facilities such as rehabilitation centers for treatment. The concept of remote treatment and home-based rehabilitation have received attention. Therefore, I propose a wrist-forearm wearable rehabilitation training/auxiliary exoskeleton with cable driven actuator for the forearm pronation/supination, wrist extension/flexion to help patients to complete ADL as well as perform rehabilitation training. The low-profile design that can fit the forearm like clothing combines features of a rail structure and tendon driving mechanism with high transfer efficiency. I conducted a biomechanical analysis to quantify the movement of wrist landmarks during forearm rotation, as well as a performance evaluation and user tests with our prototype. I demonstrate that it can provide patients with sufficient and compliant support in terms of range of motion and output torque. The user-friendly design allows patients to don and doff the device independently and quickly, as well as for individual customization. With the advantage of not restricting other joint movements, the device also shows the possibility of co-use with other rehabilitation devices.