Rehabilitation Strategies for the Lower Limb Rehabilitation Robot with Magnetorheological Damper

Lower limb rehabilitation robot plays an important role in the rehabilitation of patients with lower limb disability, However, safety and controllability remain difficult to deal with. This article investigates a kind of exoskeleton robot with 4 Degrees of Freedom, which has adjustable length, magnetorheological dampers and wire-driven system for guarantee of safety and controllability. Then, a coupling strategy is proposed for interaction between the human and the robot utilizing AnyBody Modeling System. The driving function of the robot is designed based on the Fourier expansion. Kinematics analysis is carried out, and the results indicate that the correctness of the human-machine coupling and the lower limb rehabilitation robot meets the rehabilitation needs. Finally, the maximum muscle activity and the muscle contraction force, as the evaluation criteria for the effect of rehabilitation training, are measured under the combination of different limit angles and periods of lower limb motion. Simulation results show that 12°, 24° and 30° are more beneficial to the patients in the early, middle and late stages of rehabilitation during a 6-second training cycle.