基于固定时间扰动观测器的水面无人艇精确编队控制

在水面无人艇(USV)编队控制中,控制效果易受系统初始状态和内外部扰动的影响.为此,研究一类具有复杂干扰下的USV编队控制问题,结合固定时间扰动观测器提出一种领航-跟随编队控制方法.首先,提出一种基于固定时间滑模的跟踪控制(FTSM-TC)策略,在固定时间内保证领航艇快速跟踪期望轨迹;然后,为处理内外部未知干扰设计固定时间扰动观测器(FTDO),从而保证在固定时间内对编队系统中的未建模动态和外部复杂干扰进行精确辨识.所提出的基于FTDO的编队控制(FTDO-FC)策略,使编队控制系统在固定时间内收敛并保持稳定的期望队形,仿真结果表明,所设计控制方法能够有效解决存在复杂未知扰动情况下的USV编队控制问题,且收敛时间与系统初始状态无关.

Fixed-time disturbance observer-based accurate formation control of unmanned surface vehicles

In the formation control of unmanned surface vehicles (USV), the control performance is easily affected by the initial state of the system, internal and external disturbances. In this paper, a leader-follower formation control strategy, which combines with the fixed-time disturbance observer, is proposed to deal with the problem of USV formation control. First of all, a fixed-time sliding mode tracking control(FTSM-TC) strategy is proposed, which ensures the leader USV can track the desired trajectory within a fixed time. Secondly, a fixed-time disturbance observer(FTDO) is designed to estimate unmodeled dynamics and external disturbance, which achieves accurate estimation of disturbances. The proposed FTDO-based formation control(FTDO-FC) strategy can maintain a stable desired formation, and enables that the formation control system can converge in a fixed time. Simulation results show that the proposed control strategy can effectively handle unknown disturbances, and the convergence time is independent of the initial state of the system.