Command Filter-Based Adaptive Fuzzy Tracking Control for Intelligent Ship Autopilot with Full-State Constraints

In this article, a command-filtered composite adaptive fuzzy tracking control problem is considered for intelligent ship autopilot with full-state constraints. Fuzzy logic systems (FLSs) are utilized to tackle the unknown nonlinear functions. By the method of inverse mapping to a tan-type function, the issue of full-state constraints for nonlinear systems is disposed. Through the use of serial-parallel estimation model (SPEM), the forecast bias and the track bias can change the weights of FLSs and the approximate characteristics of FLSs will be improved. Then, by constructing the command filter, the issue of complex explosion will be effectively solved. The designed control strategy can ensure the boundedness of all states in the considered system satisfies the state constraints. The output also can track the desire trajectory. Finally, the simulation example demonstrates the validity of the proposed control scheme.