GAIN-SCHEDULED CONTROL OF DISCRETIZED SHIP AUTOPILOT SYSTEM SUBJECT TO POLE-ASSIGNMENT AND PASSIVITY CONSTRAINTS

Abstract

This paper addresses a control performance problem for discretized ship autopilot system with uncertainty. To completely express the uncertainty, Linear Parameter Varying (LPV) modelling technology is employed such that the ship autopilot system is described via several linear systems and weighting function. Furthermore, gain-scheduled scheme is applied to design a controller to achieve the passivity and pole-assignment constraints. Moreover, a Parameter-Dependent Lyapunov Function (PDLF) is used to derive some sufficient conditions. Through the proposed design method, the attenuation performance and stability of the system can be guaranteed. Besides, the transient responses are furtherly improved such that the ship autopilot system possesses short settling time for abominable operation. To demonstrate the proposed design method, some numerical simulations are finally provided.