Experimental Comparison of Sliding Mode Control Dedicated Discretization Approaches

In this paper various explicit and implicit discretizations of first-order sliding mode control and super-twisting control are presented and tested in real-life experiments. At first, the performance of the discretizations is compared in experiments without any disturbances for one parameter selection. Furthermore, the accuracy of the super-twisting control discretizations is compared over varying controller gains. Finally, the discrete-time super-twisting controllers are compared in presence of a disturbance due to uncertain model parameters as well as an external disturbance. The results of the experiments demonstrate that recently published discretizations are able to avoid the undesired discretization chattering. The implicit discretization proves its constant performance independent of the selection of the parameters.