Narrow Results

It has been known that time delays may not only degrade the performance of the closed-loop control systems, but also induce instability due to the introduction of extra phase lag. The focus of this paper is to find out a way to design a robust controller for networked control systems (NCSs) with time-varying communication delays. To this aim, a mixed fuzzy-PID/neural network compensating scheme is proposed so as to alleviate the influence resulting from uncertain communication delays while maintaining system performance. A condition ensuring stability of the NCS is derived from the system's input–output viewpoint. The effectiveness and superiority of our proposed approach are fully verified in an experimentally networked pneumatic control system.

This paper studies affine formation control problem of general linear multi-agent systems (MASs) over undirected graph in the presence of time delays. Different delay conditions are considered and predictive observers are designed for the followers to predict the states in the future. Then, affine formation control laws are designed based on the predicted states, and sufficient conditions are derived to ensure the convergence of the formation errors. With an adaptive mechanism, the proposed control laws can be implemented without the usage of global information. Under the proposed protocols, the MASs can form a target formation shape and realize time-varying geometric transformations continuously. Finally, simulations are conducted to verify the effectiveness of the theoretical results.

Graphic simulation based on virtual reality technology is applied to the tele-operation robot system with tele-presence to make full use of the immersion feeling and the forecast property of the 3-D graphic stereoscopic display, which not only provides the operator with friendly work windows but also can overcome the effect of the communication time delay in tele-operation. In order to investigate the ineluctability communication time delay in force tele-presence of the tele-operation robot system, a tele-presence system based on the virtual reality is setup in this paper. The system structure, geometrical noumenon modeling, and man-machine interface are introduced in detail. In the tele-operation system, graphical robot technology is used to solve the time delay, and the relating experiments have proved the validity of the reappearance of the movement of an actual robot by a graphical robot.

In this paper, we consider the sliding mode control of delayed T-S fuzzy neural network with normbounded uncertainties. Based on the Lyapunov-Krasovskii stability theory, we originally research the sliding mode control method for T-S fuzzy neural network with time delay on the basis of the linear matrix inequalities (LMIs). A numerical example is given to validate the effectiveness of our method.