Trajectory control of lower limb exoskeleton robot with variable forgetting factor

The paper designs an appropriate iterative learning control(ILC) algorithm based on the trajectory characteristics of lower extremity exoskeleton robot, and the algorithm utilizes variable forgetting factor not only does not affect the system in the convergence speed, but also it can enhance the robustness of the system. Considering the lower extremity exoskeleton robot trajectory is periodic motion, and it can use an iterative learning control to improve the following performance of the system. Meanwhile, in order to improve the robustness of the system, using a variable forgetting factor to improve system performance, at the cost of sacrificing the speed of iteration to improve the stability of the system, and since the introduction of the variable forgetting factor enables the system to filter in iterative direction, finally gets appropriate performance indicators. Simulation results verify the feasibility of the algorithm.