基于高阶滑模控制器的水下潜器运动控制

Underwater vehicle motion control based on high order sliding controller

水下环境复杂多变,由于水流的不可预知性和多变性,潜器的水动力系数往往无法准确获取,使得依赖这种参数的潜器运动控制算法的应用受到了很大的局限。为了解决控制器对模型参数的依赖,设计了一种基于高阶滑模控制算法的模型无关控制器,并通过设置合理的过渡过程,解决了这种控制算法依赖初值的弊端。仿真结果表明,位置和姿态的控制能够快速的收敛,误差很小并且不依赖于初始条件,控制器需调节参数很少,并且算法简单,适用于工程的实际需要。

Underwater environment is highly dynamic, presenting significant disturbances to the vehicle in the form of underwater cur- rents. Additionally, the main difficulties associated with underwater control are the parametric uncertainties. The model-based controller needs precise hydrodynamic coeffcients, but in practice it is very hard or impossible. In order to avoid this problem, a model-free high order sliding mode controller is proposed, and a reasonable transient process is designed to make the controller have a good performance for any initial error condition. Performance of the proposed controller is verified using numerical simulations, and is implemented in a four freedom nonlinear underwater vehicle model. Simulation results show that exponential convergence of position and attitude is fast and that overshooting is very small for any initial condition. And the controller proposed needs few parameters to adjust. Algorithm is very easy to meet the engineering needs.