Event-triggered Tracking Control For Nonlinear Systems

In recent decades, with the development of science and technology, the analysis nonlinear systems has attracted more and more attention. One of the important problems of nonlinear systems is the tracking control which has been widely applied in robot trajectory, missile guidance, bio-medical, economic etc. However, with the development of industry, resource consumption and communication cost saving have gradually become the main demand in many areas. The traditional time-triggered scheme and the periodic sampling control methods require the continuously detection and update of the systems which result in a huge consumption of resources. In this respect, the event-triggered scheme shows a great advantage that it allows the controller update only when the triggering condition is satisfied which will save the communication costs.This paper analyze a tracking control problem of nonlinear systems with an event-triggered scheme in which the controller update only when the triggering condition is satisfied. We analyze this problem on a networked system and design the controller as a combination of continuous-time feedforward controller and an event-triggered feedback controller in which the event-triggered scheme save the communication cost but make the feedback controller piecewise constant meanwhile which may lead to bad tracking results. To make up for this deficiency, we design the feedforward controller as continuous-time which guarantee the tracking accurate. The combination of these two parts make our algorithm efficient and accurate which could not be satisfied simultaneously in existing works.Comparing with the existing works, the main contribution of this paper is that this paper address the tracking problem of nonlinear systems with an event-triggered scheme which save the communication. This paper solve the tracking problem on a networked system in which the network transfers the event-triggered controller to the actuator. Moreover, the output of the controlled system tracks the reference trajectory accurately.In this paper, we study the tracking problem and transfer it to a stabilization problem by defining the tracking error. We design the event-triggered feedback control with the backstepping method and then analyze the stability with a Lyapunov function. We also prove that the output of the system will track the reference trajectory exactly without Zeno behavior. In the last part, we illustrate out theoretical results with a simulation example.