In this study, a new development of knee exoskeleton is presented. This structure helps people who have difficulties in walking, especially those whose knee functions are broken or weak. The design includes 3 main components: motor, damper, and mechanical frame. | Science and Technology Development Journal Vol 21; Issue 01 Viet Nam National University Ho Chi Minh City, Viet Nam Science and Technology Development Journal ISSN: 1859-0128 Volume: 21 Issue: 01 Journal homepage: www. Dynamic analysis of knee-exoskeleton and its implementation in design of magnetorheological damper Bui Quoc Long Mai, Van Chi Le, Tran Huy Thang Le, Xuan Phu Do* MediRobotics Laboratory, Department of Mechatronics and Sensor Systems Technology, Vietnamese German University, Binh Duong, Viet Nam ARTICLE DETAILS History Received: 04 April 2018 Accepted: 12 May 2018 Published: 02 June 2018 Keywords ANSYS ADPL, Force analysis, Knee exoskeleton, Moment analysis, MR damper, Optimization ABSTRACT In this study, a new development of knee exoskeleton is presented. This structure helps people who have difficulties in walking, especially those whose knee functions are broken or weak. The design includes 3 main components: motor, damper, and mechanical frame. The user movement is controlled by using a magnetorheological (MR in short) fluid in the damper. The operation of the damper is based on the change of viscosity of MR fluid to variations in the magnetic environment. To design the damper, kinematic parameters of the proposed exoskeleton were analyzed to find relations among forces and torques. After analysis, the function of the damping force was established. The magnetic flux density and yield stress functions were also found; these functions are the basis for derivation of the damping force formulation. The forces from the exoskeleton are directly related to the damping force. Hence, these functions are used as an objective function to find the optimized geometry of the damper. The optimization process was done using ANSYS ADPL. Our study showed that the requirements for the design of the damper can be obtained and used in manufacturing in the future. © 2018 Viet Nam National University Ho Chi Minh City, Viet
