本文针对海底地形测绘时自主水下航行器(autonomous underwater vehicle,AUV)的变深控制问题,提出具有PID增益调节的AUV深度控制方法,基于反馈增益的反步法设计控制器,避免了采用传统反步法导致控制器中存在虚拟控制量的高阶导数问题;基于李雅普诺夫稳定性理论设计控制器参数消除了部分非线性项,得到的控制器的线性部分为状态变量的线性组合,具有PID控制器参数调节的形式;针对存在建模不精确、外界干扰和测量噪声时的闭环系统鲁棒性进行分析,保证了误差系统在扰动作用时的一致最终有界性.最后通过仿真实验验证了本文设计的控制器的有效性.
To deal with the problem of diving control for an autonomous underwater vehicle (AUV) in oceanographic mapping survey, we propose a depth control method with PID gain tuning function. In designing the controller, the require- ment of the higher order derivative of virtual control variable is eliminated by adopting the backstepping method based on the feedback gain instead of the traditional backstepping method. Part of nonlinear terms is removed in the design of con- troller parameters by using Lyapunov stability theorem, resulting in a linear controller which is composed of state variables with PID gain tuning function. Robustness analysis is performed on the system which is uniformly ultimately bounded in the presence of model uncertainties, external disturbances and measurement noises. Simulation results show the validity and the effectiveness of the proposed controller.