电磁力滤波与快速反射镜光学补偿在潜航器光轴稳定控制中的应用

搭载在潜航器上的光电桅杆是光电跟瞄的重要装置.当潜航器在水下高速行进时,海水会在物体表面形成脱体边界层和涡街,涡街的生成和脱体会引起阻力和升力的大幅度波动,从而对光轴稳定性产生极大的扰动.本文首先基于电磁场和流体力学的基本控制方程,通过层次结构网格下的有限体积法探讨了电磁流体表面控制对潜航器绕流流场的影响和消涡减振效果;其次,分析并获得了快速反射镜(fast steering mirror,FSM)的结构特性、传递函数和PID控制策略;最后,以潜航器光路模型为研究背景,结合电磁流体的滤波特性和FSM的传递函数,论证了复合控制对潜载光电跟瞄系统稳定性提高的效果.结果表明,壁面流向电磁力能很好地调控潜航器绕流边界层,抑制涡激振动、减少光学系统的输入噪声,在此基础上通过FSM实现二次补偿,可以进一步提高光学系统跟踪的精度.本研究是电磁流体控制在光电领域的探索,也是对传统流体力学实验方法的拓展,因此具有一定的科学意义和实用价值.

Lorentz force filtering and fast steering mirror optical compensation in optical axis stability control for photoelectric mast

The photoelectric mast equipped on the underwater vehicle is the key equipment for photoelectric tracking. While the vehicle moves under water, especially, at high speed, more complex vortexes are generated at the surface, which will give rise to great disturbance to the stability of optical axis. In this paper, firstly, based on the basic control equations of electromagnetic field and fluid mechanics, the effects of the Lorentz force on flow field structure and vortex induced vibration are numerical simulated with using the finite volume method with hierarchy grids. Secondly, the structural characteristics, transfer functions and PID control strategies of fast steering mirror (FSM) are analyzed. Finally, combining the transfer function of FSM and the force characteristics, the effect of the composite control on the stability of submarine photoelectric tracking system is discussed by MATLAB. The results show that the Lorentz force can adjust the boundary layer and suppress vortex induced vibration, based on which the FSM can be used to further improve the accuracy of the optical tracking system. This research offers a new exploration in the field of electromagnetic fluid control, as well as a novel development of the traditional research direction of fluid mechanics. Therefore it appears to have a certain scientific significance and practical value.