Modeling and Synergetic Simulation of a Lower Limb Exoskeleton Robot With the Human Subject

This paper conducts the study on the dynamic modeling and simulation of a lower limb exoskeleton with the human subject in the loop. Lagrangian method is used for the theoretical derivation and formulation of the dynamics of the synergetic human-exoskeleton system. The standing-up motion of the human subject from a chair is simulated for demonstration in MSC ADAMS software. The associated joint angles of both the human subject and exoskeleton robot are recorded and compared for studying the synergetic effect between the human subject and exoskeleton robot. The simulation results show that there are certain amount of motion discrepancy between the human subject and lower limb exoskeleton during operation, which makes accurate control difficult and could even lead to possible unbalance of the entire human-exoskeleton system.