Time-delay Analysis And Sliding Mode Control For Teleoperation System

Internet-based teleportation system is a complex time-delay system, which enable slave track master’s movement in order to carry out tasks in dangerous environments such as in the space, under the sea and in nuclear radiation environment ect. Thus teleoperation system in many fields has potential applications and great challenges in both application and theory. With the rapid improvements of computer network, the communication of teleoperation system is replaced by Internet. But the random time-delay of Internet always affects the performance of teleoperation system, and even makes the system unstable. To solve the problem, firstly, the time-delay of Internet was analyzed and tested, and then the research on teleoperation system was discussed. Main research works of this paper are as follows:Firstly, due to the impact of teleoperation system on Internet, the characteristics about network time-delay of the Internet were analyzed and researched. Test software is compiled by Visual C++in order to test the communication time-delay based on network. The probability density distribution on network time-delay was analyzed. One kind of gamma distribution and parameter estimation which meets the demand of network time-delay was pointed out. A time-delay generator was designed which used in simulation block diagram later.Secondly, system performance was affected by communication time-delay between master and slave. The application of the sliding mode control algorithm in teleoperation system is discussed. Chattering problem was solved which existed in sliding mode by using of saturation functions. The simulation carries out velocity track and force track between the master and the slave.Finally, combining the control of teleoperation system requirements, fuzzy theory is imported. A design method of fuzzy sliding controller is proposed which can resolve the chattering problem. It can establish a fuzzy system which based on fuzzy switching gain adjustment of the sliding mode control system by using fuzzy rules.The result of research indicates that the type of fuzzy sliding mode control algorithm has good performance and strong robustness.