Comparision of Joint Space and Task Space Integral Sliding Mode Controller Implementations for a 6DOF Parallel Robot

摘要

Controllers for parallel manipulators can be designed in task space or joint space, each having its own advantages and disadvantages. In this paper, integral sliding mode controllers designed in joint space and in task space are compared using MATLAB simulation. In both cases, genetic algorithm is used to determine optimal sliding surface gain. The performance and robustness, smoothness of control signal and ease of implementation of the controllers is compared using a smooth trajectory. The performance of the controllers is measured by the mean square value of the tracking error over the whole trajectory while robustness is compared by the percentage error increase in mean square error between no load and full load conditions. Extensive simulations showed that joint space implementation gives slightly bigger mean square error value but needs a small control effort. The control signal is also very smooth in case of joint space.