The New Jersey Institute of Technology's
Electronic Theses & Dissertations Project

Title:	Cycloidal-drive joint design for wearable exoskeletons
Author:	Rawal, Abhi J.
View Online:	njit-etd2020-080 (xii, 76 pages ~ 3.2 MB pdf)
Department:	Department of Mechanical and Industrial Engineering
Degree:	Master of Science
Program:	Mechanical Engineering
Document Type:	Thesis
Advisory Committee:	Lu, Lu (Committee chair) Zhou, Xianlian Alex (Committee member) Ji, Zhiming (Committee member)
Date:	2020-12
Keywords:	Cycloidal transmission Backdrivability Compactness Rehabilitation robotics Wearable exoskeleton
Availability:	Unrestricted
Abstract:	This thesis's scope was to construct a highly back drivable and compact joint design that can be used for wearable exoskeletons specifically designed to assist with rehabilitation. A compact cycloidal gear transmission was designed to satisfy the compactness requirement while ensuring the minimum torque is required for backdriving the mechanism. The joint was designed based on the compact cycloidal drive specifications, and the backdrivability test was performed to measure the minimum torque required (1.20 Nm) to backdrive. The joint design incorporates various important features such as rotation lock feature to prevent hyperextension, a housing design that offers the benefit of using the joint for the left and right limb, a motor mount that securely holds a brushless DC motor, and a sensor bracket that securely positions a control sensor over the motor for controlling the motor position and speed. Successful evaluation of the 3D printed prototype validated the integrity of the design.