基于大倾角的角锥体空间后方交会研究

Research of pyramid space resection based on large angle of inclination

在摄影测量中,当倾角变大时,由于三角函数的多值性和奇异性导致传统的共线条件方程线性化的空间后方交会方法已经不能稳定地求解出摄影瞬间影像的外方位元素。文中通过对传统空间后方交会、基于单位四元素的空间后方交会和文中所用到的基于简化的DLT线性方程求解线元素初值的角锥体法比较发现,在像片倾角逐渐变大,传统方法和四元素法不能正确求解出外方位元素的情况下,基于角锥体法的空间后方交会仍能稳定、准确地求解出像片的外方位元素。

In photogrammetry,when the angle of inclination was large,elements of exterior orientationas could not be worked out steadily any more through method of space resection based on traditional collinearity equation linearization as a result of trigonometric function＇s ambiguity and singularity.In this paper,we proposed a pyramid method based on simplification DLT equation to calculate initial value of line elements.By comparison with traditional space resection and space resection based on unitquaterinon,we find that this method could obtain steady and accurate elements of exterior orientation.