针对超空泡航行体的弱阻尼和耦合特性,提出采用内外回路的设计思想.用俯仰角反馈来对弱阻尼的动态特性进行镇定,并与运动学进行解耦.再根据深度信号作为输出,对以运动学方程为主的主回路进行设计.对所设计的系统用Nyquist法进行了理论分析,结论是这种用回路和带宽来确定反馈增益的做法是很有效的,既能满足深度控制的良好性能要求,又能保证姿态回路的稳定性.通过在扰动作用下的仿真对这个结论进行了验证.所提出的这种设计的每一步都有明确的物理解释,为状态反馈设计提供了一种新的思路,具有推广价值.
Because of the coupling effect and lightly damped dynamics of the high-speed supercavitating vehicle(HSSV),a decoupling inner-outer loop design is proposed.The pitch angle can be considered as a feedback signal of the inner loop which is used to stabilize the lightly damped mode and to decouple the vehicle dynamics from the kinematic movement.The depth signal was then used as an output for the main loop which was dominated by the kinematic equations of the vehicle.The resulting design was theoretically verified by the Nyquist theory.It is noticed that the determination of system gain by using the concepts of loops and bandwidth is proved to be useful.Simulation result for HSSV under external disturbances was presented.It is noticed that there are explicit physical meanings in each of the design steps,so the proposed method may be further used as an alternative approach for state feedback design.