Simulation and Comparison of Event-Triggered Sliding-Mode Control Algorithms for Nonholonomic WMR

This paper focuses on the simulation and comparison of event-triggered sliding-mode control algorithms (ETSMCAs). From the previous works, two types of ETSMCAs were presented and applied to solve the tracking task. The first type is the first-order event-triggered sliding-mode control (SMC), and the second type is the traditional event-triggered super-twisting sliding mode algorithm (ET-STA). Then based on the two types, we propose a dynamic event-triggered super-twisting sliding mode algorithm (DET-STA), in which a novel dynamic event-triggering condition (DETC) is meticulously designed according to two scenarios of the sliding mode variable s(t) (i.e.,signs(t<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">i</inf>) = signs(t) and signs(t<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">i</inf>) ≠ signs(t)) and Lyapunov stability theorem. The analysis shows that the proposed method not only reduces the chattering effect but also enhances the rate of convergence during the reaching phase by incorporating both linear and integral terms. Simulation and comparison of all the presented ETSMCAs are given in detail to evaluate the theoretical results. Finally, based on the simulation results, the superiority of the proposed algorithm over the two types of algorithms mentioned above is demonstrated.