Simulation Platform for Dynamic Modeling of Lower Limb Rehabilitation Exoskeletons: Exo-H3 Case Study

Abstract

A flexible simulation platform for human gait with exoskeletons is presented to support the analysis of the human-robot interaction and performance assessment of control strategies design, e.g., assist-as-needed. The platform includes the dynamic modeling of the lower limb’s exoskeleton-human with six degrees of freedom in sagittal plane, actuated by servomotors, where the movement equations are explicitly obtained through the Euler-Lagrange approach. The full model is hybrid and it contains four sub-models that are switched between themselves according to the gait cycle phases; also, it comprises the joint actuators dynamics and the low level control system, this modeling was assembled in Simulink-Matlab. It is shown that the proposed platform is a useful tool for assistance control strategies in the gait rehabilitation. Furthermore, simulation results for the Exo-H3 exoskeleton show the successful tracking of angular trajectories, the level of human participation, and the realistic torques.