Network-based fuzzy decentralized sliding-mode control for car-like mobile robots

In this paper, the trajectory tracking of a car-like mobile robot (CLMR) using network-based fuzzy decentralized sliding-mode control (NBFDSMC) is developed. The scaling factors and the coefficients of the sliding surface for the control of the steering angle and forward-backward velocity of a CLMR are adopted by that for the control of two motors. Due to the delay transmission of a signal through an Internet and wireless module, a revision of fuzzy decentralized sliding-mode control (FDSMC) with suitable sampling time (i.e., NBFDSMC) is accomplished by the quality-of-service (QoS). The proposed control can track a reference trajectory without the requirement of a mathematical model.. Only the information of the upper bound of system knowledge (including the dynamics of the CLMR, the delay feature of Internet network, and wireless module) is required to select the suitable scaling factors and coefficients of sliding surface such that an excellent performance is obtained. In addition, the stability of the closed-loop system in the presence of time-varying delay is addressed. Finally, a sequence of experiments including the control of unloaded CLMR and the trajectory tracking of CLMR is carried out to consolidate the usefulness of the proposed control system.