Triangulation of Airborne Three-line Images Using Unit Quaternion

In this paper the unit quaternion is used as a substitute for describing the attitude of a camera to overcome the shortcomings of Euler angles on the description and interpolation of orientation, corresponding collinearity equation is then derived and linearized. At the same time the Spherical linear Interpolation (Slerp) of unit quaternion is introduced into the bundle adjustment of three-line imagery with orientation image method. By making use of Slerp formula to accomplish uniform interpolation of camera attitude on the sampling cycles between two orientation images, new mathematic model based on unit quaternion for the reconstruction of the exterior orientation parameters of three-line images is set up. Two ADS40 datasets have been used for validating related algorithms proposed in this paper. Experimental results show that bundle adjustment based on unit quaternion achieves the accuracy of about one pixel both in horizontal and height directions when locating a full control point at each corner of the block. It provides us an ideal and robust approach for the calibration and triangulation of three-line array CCD sensor.