基于修正平行投影法的飞行姿态测量

摄影系统的成像满足透视投影模型,使用平行投影法做飞行姿态交会存在模型误差。依据在目标成像的中轴线通过像面中心的时候,平行投影法和透视投影法有相同的成像特征这一事实,提出了一种无模型误差的修正平行投影法。在判读出目标图像中轴线的斜率K和截距L的情况下,假设摄影系统的高低角再旋转atan(L/K)度,使得旋转后图像的中轴线过像面的中心点。依据透视投影模型,计算出旋转后图像中轴线的斜率,再使用此斜率做平行投影交会。仿真结果表明,该方法可以很好的消除由平行投影模型带来的模型误差,为空间目标姿态交会提供了更精确的计算结果。

Flying pose measurement based on modified parallel projection method

Imaging of photography system satisfies the perspective projection model. Flying pose measurement based on parallel projection method would bring model error. Based on perspective projection model,a modified parallel projection method for flying pose measurement is proposed. This approach utilizes the fact that if the centerline of target image gets through the center point of the image plane,perspective projection and parallel projection must have the same image-forming property. According to the slope value K and intercept value L which are interpreted through target image,elevation of the photography system was supposed to rotate by atan(L/K) degree,then the centerline of target image should get through the center of image plane. The new slope value K＇of the target image's centerline can be recalculated by perspective projection model. With this new slope value K＇,the parallel projection method can produce an accurate result with no model error. Simulation results show that model errors can be eliminated by this method commendably,and more accurate pose measurement result can be gained.