一种UUV水平运动非线性控制方法

Study on a nonlinear control method of UUV horizontal movement

针对UUV水平运动时干扰因素多,不能建立准确动力学模型,难以保证控制品质的问题,采用滑模模糊控制方法,根据直舵机阶跃响应曲线,确定模糊控制器规则表,将模糊控制器的每个规则确立为一个滑模控制器,由模糊控制器确定系统的控制量,并以某型UUV为例,设计滑模模糊控制器。经仿真并与比例控制进行对比,结果表明,当存在干扰时,比例控制下UUV水平运动产生较大幅度振荡甚至失稳,滑模模糊控制下UUV仍然能保持稳态航行,震颤很小,鲁棒性好。

The UUV dynamics model is hard to be built because it suffer from uncertain disturbances.The rules table of fuzzy controller is determined by open loop step response for maximal and minimal rudder.The system control function is determined by output of fuzzy controller.Taking a UUV for example,its controller is designed by this method and is tested by computer imitation.It is proved that when the liquid disturbances existing,the lateral movement's overshoot will become bigger and even lose stability under proportional control.But under sliding mode fuzzy control,the UUV will keep steady state and sailing as desired trajectory.The system's chattering is alleviated and robustness is improved.