Discrete-Time Implementation of Super-Twisting Control with Semi-Implicit Euler Method

In this brief, a new discrete-time implementation is proposed for the super-twisting control with a semi-implicit Euler method. In contrast to the conventional realization methods, the proposed implementation scheme exploits two signum functions in the super-twisting algorithm (STA) such that the numerical chattering is totally avoided and the control precision is enhanced in terms of smallest control errors in the steady state. It has an advantage that the control accuracy is insensitive to the gain overestimation of STA, which benefits the gain tuning of the STA in practice. These superiorities of the proposed scheme are demonstrated through simulations and comparisons with other state of the art relevant to STA realization methods.