结合面阵成像的摆镜扫描系统设计研究

Study on Design of Scanning Mirror System for Area Array Imaging

为实现低轨卫星对地面热点区域快速、大范围的成像侦查,对面阵成像摆镜扫描系统的设计进行了研究。基于反射镜摆动扫描展宽相机视场的原理,根据卫星轨道高度、地面分辨率,确定扫描系统采用阶梯式的步进扫描,要求摆镜快速摆动快速稳定。给出了摆镜扫描系统的组成、技术指标和构型,采用TRUM-60旋转行波超声电机作为驱动电机。对设计的摆镜系统建立虚拟样机模型进行仿真,设计的摆镜模态满足系统使用要求。用ADAMS软件对摆镜系统进行动力学仿真分析,摆镜单步运动满足50ms快速摆动、50ms快速停止稳定成像的要求;1个运动周期内摆镜的运动状况与设计要求一致,前1 000 ms内完成10次快摆快稳的步进扫描,回程用时少于200ms,完成1行扫描的时间充裕。设计的摆镜扫描系统能完成面阵扫描,实现宽幅成像。

To realize fast and wide range imaging detection of hot spots on the ground with low earth orbit(LEO)satellite,the design of scanning mirror system for area array imaging was studied.Based on the principle of scanning mirror for expanding the camera field,stepped scan was used in the scanning system according to the orbit altitude and ground resolution,in which the scanning mirror would be fast swinging and fast steady.The composition,specification and structure of the scanning mirror system designed were given.The TRUM-60 traveling wave-type rotary ultrasonic motor was used as driving motor.Virtual prototype of the designed mirror system was modeled and simulation was carried.The modal of the designed mirror meets the system requirement.The dynamics of the scanning mirror system was analyzed by simulation with ADAMS software.The one step motion of the mirror meets the requirements which are fast swinging in 50 ms and fast steady and imaging in 50 ms.The mirror motion in one cycle is consistent with the design requirement.It can implement 10 times step scanning with fast swinging and fast steady in the first 1 000 ms and return time was less than 200 ms.There is plenty time to finish one line scanning.The scanning mirror system designed can realize area array imaging and wide swath imaging.