Research on lower limb exoskeleton suppleness control based on fuzzy variable impedance method

The lower limb rehabilitation exoskeleton is primarily used to assist patients with movement disorders in completing rehabilitation training using medical equipment, but due to its complex structure, and the need to interact with people in real time, the design of its control system has a high degree of difficulty. In this paper, the mechanical structure of the lower limb exoskeleton is designed, and then the human-machine coupled dynamics equation of the lower limb exoskeleton is established based on the Lagrange method. A fuzzy variable impedance control method is proposed for lower limb exoskeleton, which uses fuzzy mathematical theory to adjust the parameters of the impedance controller in real time to achieve the optimal control, and then regulates the interaction force between man and machine to increase the flexibility of the system. The designed fuzzy variable impedance control method is simulated and analysed on the joint simulation platform of ADAMS and MATLAB/Simulink to verify the superiority of the control system.