一种多目标引导成像参数和偏流角一体化计算方法

An Integrated Calculation Method of Multi-target Guided Imaging Parameters and Drift Angle

针对卫星执行多目标实时引导成像任务时,星上求解成像参数与偏流角补偿存在耦合,相机指向变化会带来偏流角和姿态变化,进而影响视线指向和偏流角修正精度的问题,文章基于携带一维摆镜的延时积分电荷耦合器件(TDICCD)相机的实时引导成像卫星,提出一种多目标引导成像参数及偏流角一体化计算方法,选择一致的坐标系和公共变量,推导了迭代计算成像参数求解和偏流角的计算过程,通过绕瞬时虚拟光轴旋转进行偏流角补偿,得到相对平缓的偏流角控制目标值用于姿控跟踪。该方法经浦江一号(PJ-1)卫星在轨验证,结果表明:在多目标成像的典型工况下,可在2个控制周期内将摆镜摆角改变引起的偏流角偏差修正到0°附近,摆镜动作引起的三轴姿态突变量小于0.5°,有利于控制系统在较短的时间内跟踪到位。

When satellites perform multi-target imaging tasks,there is a coupling between solving imaging parameters and drift angle compensation control.Changes in camera pointing will cause drift angle and attitude change,which will affect the accuracy of camera pointing and drift angle correction.In response to the above problems,this paper proposes an integrated calculation method for multi-target guided imaging parameters and drift angle based on a satellite carrying a one-dimensional pendulum mirror with a delay-integrated charge-coupled device(TDICCD)camera.The appropriate coordinate system and common variables are selected,the iterative calculation process of imaging parameters and drift angle is derived,and the drift angle is compensated by rotating around the instantaneous virtual optical axis,and a relatively smooth drift angle control target value is obtained for attitude control tracking.This method has been verified by Pujiang-1(PJ-1)satellite in orbit,and the results show that under the typical working conditions of multi-target imaging,this method can reduce the deviation of the drift angle caused by the swing angle of the swing mirror within 2 control periods.Corrected to near 0°,the three-axis attitude change caused by the swing mirror action is less than 0.5°,which is beneficial for the control system to track in place in a short time.