时滞时变AUV的模糊变结构控制

针对自主水下航行器(autonomous underwater vehicle,AUV)具有时变的水动力学系数的现象,为了实现其鲁棒控制,设计了一个模糊变结构控制器.该控制器以变结构控制的切换函数及其变化率为模糊控制器的输入,以变结构控制律的变化率为模糊控制器的输出.为了提高控制器的性能,引入了压缩扩张隶属度函数.通过将该控制器和均分隶属度函数模糊变结构控制器、准滑模控制器的仿真对比,证明了设计的控制器具有更好的性能.数值仿真表明,该控制器能很好地实现对具有控制输入时滞和时变水动力系数AUV的深度控制,且稳定后基本无抖振现象.

Fuzzy sliding mode controller for time-delay and time-varying autonomous underwater vehicles

As an autonomous underwater vehicle(AUV) is a strongly nonlinear system with time-varying hydrodynamic parameters,a fuzzy sliding mode controller is presented to achieve the robust control.The switching function of variable structure control and its derivative are used as inputs of the fuzzy controller,and the derivative of variable structure control is used as outputs of the fuzzy controller.The design method of the controller offers a systematical means of constructing a set of shrinking-span and dilating-span membership functions for the controller.The contrast simulation results indicate that the proposed controller can achieve more satisfactory performance than the traditional fuzzy sliding mode controller and the quasi sliding mode controller.The controller is applied to dive plane control based on the models with hydrodynamic parameter uncertainties and input time-delay.Simulation results demonstrate the effectiveness of the controller with low energy consumption and chattering reduction.