应用坐标变换动态修正光电经纬仪脱靶量

Dynamic correction of target deviations for photoelectric theodolites by coordinate transform

分析了目前采用的脱靶量修正模型的适用条件,采用坐标变换法推导出经纬仪脱靶量修正公式,获得了与球面三角学相一致的推导结果,并在此基础上推导出成像系统无照准轴平行约束条件的通用脱靶量合成公式。采用光学系统的物方焦点作为摄像机系统的投影中心,推导出投影中心与经纬仪回转中心不重合条件下摄像机投影中心在测量坐标系中的坐标值。经测量设备的实际验证表明,该修正方法突破了现有修正模型的局限性,适用于多传感器经纬仪成像系统。对于水平不平行度为6.13°,物方焦点到固联中心的距离为0.247m的成像系统,脱靶量合成修正误差<16.0″(高低角为65°);投影中心位置误差<0.04m。

A correction formula for target deviations is derived by using the coordinate transform and its suitable conditions are proposed. Experiments show that it is coincident with the spherical trigonometry well. A new correction model for the target deviation is deduced when the optical axis is not parallel to the collimating axis, and the coordinates of the camera projection center in measuring coordinate systems are calculated in conditions of the mismatching between the optical center and the theodolite rotation center by using the object focus optical system as the projective center of camera system. A practical test proves that the approach breaks through the limitation of existing model, and is suitable for multi-sensor imaging systems of theodolites. When the level parallelism.is 6. 13°and the distance is 0. 247 m between the object focus and the solid joint center, the target deviation of the imaging system is less than 16.0＂（ elevation is 65°） , and the projection center position error is less than 0.04 m.