基于车载平台的快反镜光轴稳定技术

摘要

为了满足车载平台光轴稳定的应用需求,采用压电陶瓷作为驱动器对快反镜进行了结构设计,将其作为仿真模型对快反镜进行了模态分析和力学仿真,并对结构进行了优化设计.采用高帧频相机探测的质心位置作为反馈信号,利用现在可编程门阵列进行高速图像处理,研制出适用于车载平台的光轴稳定快反镜.对快反镜的性能参量进行了全面测试,并参与了集成联调试验.结果表明,该快反镜的分辨率约0.4μrad,闭环带宽大于100Hz;三级公路上,汽车以40km/h行驶过程中,在无人值守模式下,由总控对快反镜进行控制,与开环相比,闭环后光轴x轴抖动均方根减小3.6倍,y轴减小2.1倍,20Hz以内的光轴抖动抑制效果明显,取得了较好的试验效果.该系统具有高带宽、高精度及高稳定性的特征,对车载平台的光轴稳定起着重要作用.%In order to meet application requirements of optical axis stabilization on a vehicle platform,compositions of the optical axis stabilization system were introduced and selection requirements of the driver of a fast steering mirror(FSM)were analyzed.With piezoelectric ceramics actuators as the drivers for the FSM,modal analysis and mechanical simulation of the FSM were carried out and the structure design was optimized.Using the position of centroid detected by high frequency camera as feedback signal,high speed image processing was made with field-programmable gate array,and a FSM for optical axis stabilization based on vehicle platform was developed.Performance parameters of the FSM were tested.After integration test,it is found that the resolution is about 0.4μrad and the bandwidth of the closed loop is more than 100Hz.With the car running at 40km/h on a three-level road,with the FSM controlled by the central computer in unattended mode,the root-mean-square jitters on x and y axes of the closed loop decreases 3.6 and 2.1 times of that of the open loop respectively.The suppression effect of optical axis jitter within 20Hz is obvious and preferable test result is obtained.The system has characteristics of high bandwidth,high accuracy and high stability,and plays an important role in the optical axis stabilization on a vehicle platform.