Event-triggered sliding mode control using new triggering rules

We propose an event-triggered sliding mode control scheme for a class of nonlinear uncertain systems. The controller ensures f inite-time convergence of the system trajectories to a prescribed neighborhood of the sliding surface, followed by convergence to a neighborhood of the origin. The size of the sliding surface neighborhood is independent of the uncertainty bound, although it influences the event-triggering frequency. The combination of standard sign-based switching control with event-triggered implementation may give rise to Zeno behavior in the presence of system uncertainties. To prevent this behavior, we approximate the discontinuous switching functions by Lipschitz continuous ones and design the event-triggering rule to preserve stability while eliminating potential Zeno behavior. The effectiveness of the proposed approach is demonstrated through two examples, namely, an inverted pendulum and a flexible-joint manipulator.