Authors: Sana Bembli; Nahla Khraief Haddad; Safya Belghith
Addresses: RISC Laboratory, National Engineering School of Tunis, University of Tunis El-Manar, Tunis, Tunisia ' RISC Laboratory, National Engineering School of Tunis, University of Tunis El-Manar, Tunis, Tunisia ' RISC Laboratory, National Engineering School of Tunis, University of Tunis El-Manar, Tunis, Tunisia
Abstract: This paper deals with a new control approach of an exoskeleton-upper limb system. The considered system is a two-DoF robot in interaction with an upper limb used for rehabilitation. The objective is to control the flexion/extension movement of the shoulder and the elbow joints in presence of disturbances. First, the modelling and the control of the system using different laws were made, and a stability study is realised. Then, a comparison study between these different algorithms was done. To prove the performance of the tested controllers, a robustness analysis was needed. For that, a state of the art of different robustness analysis methods was presented. The application and the comparison between these methods were realised to obtain the most robust one. Finally, the control of the exoskeleton-upper limb system by the model free terminal sliding mode is developed. A Monte Carlo study is done. The performance and the robustness of the model free terminal sliding mode algorithm in presence of disturbances and uncertainties are provided by simulation results.
Keywords: exoskeleton-upper limb system; dynamic model; rehabilitation; robust controller; robustness analysis; uncertainties and disturbances; stability study; Monte Carlo simulation.
International Journal of Mechatronics and Automation, 2021 Vol.8 No.4, pp.217 - 228
Received: 12 Nov 2020
Accepted: 27 Aug 2021
Published online: 18 Jan 2022 *