基于压电陶瓷直驱的前向像移补偿系统

摘要

Forward motion compensation (FMC)system for airborne area mapping camera is designed, and the working schedule is presented.The FMC system uses piezoceramic actuator to drive the focal plane module directly.The piezoceramic actuator works at position close loop mode whose given posi-tion is set incrementally.This makes focal plane module move at desired speed so that forward motion speed can be compensated.Experiments imply that the maximum FMC residual error of the FMC sys-tem is 0.38μm when the forward motion velocity is 2.5 mm/s and the maximum residual FMC error is 0.48μm when the forward motion velocity is 3.5 mm/s.The residual errors are far less than one third of the pitch dimension.The FMC frequency is 25 Hz which satisfies the demand of high frequency aerial FMC while the maximum exposure time is 20 ms.%为补偿面阵测绘相机航摄成像过程中的前向像移,设计了采用压电陶瓷驱动器直接驱动焦平面组件的前向像移补偿系统,给出了前向像移补偿系统工作时序.压电陶瓷驱动器工作于位置闭环模式,通过斜坡递增设置压电陶瓷驱动器位置给定,使压电陶瓷驱动器驱动焦平面组件以期望速度移动,补偿前向像移速度.实验结果表明,前向像移速度为2.5 mm/s时,前向像移补偿系统最大像移补偿残差为0．38μm；前向像移速度为3．5 mm/s 时,最大像移补偿残差为0.48μm,远小于1/3像元尺寸.相机最长曝光时间为20 ms时,前向像移补偿频率可达25 Hz,满足高频航测成像前向像移补偿需要.