Abstract
Aiming at the decrease of tracking accuracy caused by nonlinear friction and strong coupling of the flexible upper-limb exoskeleton, an improved super-twisting sliding mode controller (ISTSMC) is proposed. Compared with the conventional super twisted sliding mode controller (STSMC), this method can replace the switching function under the integral term with a nonsmooth term, resulting in a faster response, less vibration when performing trajectory tracking, and reduced steady-state error. The introduction of the nonsmooth term causes the controller to have a stronger anti-interference ability. At the same time, the parameters of the ISTSMC can be adjusted in order to achieve the expected control performance. The effectiveness and feasibility of the proposed control algorithm are verified through experiments.
Funder
National Natural Science Foundation of China
Natural Science Foundation of Jiangsu Province, China
Subject
Control and Optimization,Control and Systems Engineering
Reference23 articles.
1. Changes in mortality in top 10 causes of death from 2011 to 2018;Rana;J. Gen. Intern. Med.,2021
2. Robotics-assisted mirror rehabilitation therapy: A therapist-in-the-loop assist-as-needed architecture;Shahbazi;IEEE/ASME Trans. Mechatron.,2016
3. A neurophysiological approach to nerve transfer to restore upper limb function in cervical spinal cord injury;Mandeville;Neurosurg. Focus,2017
4. Prange, G.B., Jannink, M.J., Groothuis-Oudshoorn, C.G., Hermens, H.J., and IJzerman, M.J. (2009). Rehabilitation Robotics, Gerdienke Prange.
5. SCRIPT passive orthosis: Design of interactive hand and wrist exoskeleton for rehabilitation at home after stroke;Ates;Auton. Robot.,2017