A Rehabilitation Training Interactive Method for Lower Limb Exoskeleton Robot

Rehabilitation exoskeleton robot plays an important role in rehabilitation training for limb-disabled patients and exoskeleton robots are becoming popular in rehabilitation area. To encourage the patient's active participation, the patient's subjective motion intention needs to be considered. In this paper, a rehabilitation training interactive method of lower limb exoskeleton robot based on patient's intention is proposed. The proposed method benefits patients to adjust the training trajectory in a safe range of motion according to their intentions. That is, the patient can adjust the amplitude of the trajectory and even the initial point of the trajectory by applying external interaction force to the human-robot system. To identify the patient's intention, the classical momentum observer is introduced to detect the interaction force between the patient and the exoskeleton. In addition, joint space trajectories and Cartesian space trajectories with different amplitudes are designed to enrich the training contents. Then, a trajectory switching algorithm based on external interaction recognition and designed training trajectories is developed. Finally, the proposed method is supported by the simulation results on a lower limb exoskeleton with 2 degrees of freedom (DoF).