Because of the close range photogrammetry has wide measuring range, high precision and high efficiency, the precision measurement of large size tasks take more and more important role Among them, the self-calibration measurement model based on adjustment optimization is the important reason to ensure the method to achieve high-precision measurement. However, with commercial grade SLR camera more and more applied to three-dimensional measurement, the measurement accuracy and the professional camera compared to a certain gap A large number of analyses have found that, in addition to the camera itself, the self -calibration model relies too much on the internal parameters of the camera, especially the distortion parameter, which is the important reason leading to the decrease of the measurement accuracy. In order to reduce the influence of the parameterized model on the measurement results, we propose a photogrammetric method that does not rely on the intrinsic parameters of the camera. Firstly, a non-parameterized calibration method for large field of view camera is designed by combining the perpendicular method and Zeiss calibration method. Then, the non-parameterized measurement model based on the angle information can be established after the matching of the same point and the initial value of the difference between different images. Finally, combined with adjustment optimization algorithm, the three-dimensional coordinate of the measured point in space is calculated accurately. Compared with the traditional photogrammetry results, it is proved that this method can effectively improve the photogrammetric accuracy of the large field SLR camera.
During the spacecraft assembly process, the posture of the aerospace camera to the spacecraft coordinate system needs to be measured precisely, because the posture data are very important for the earth observing. In order to measure the angles between the camera optical axis and the spacecraft coordinate system’s three axes x, y, z, a measurement scheme was designed. The scheme was based on the principle of space intersection measurement with theodolites. Three thodolites were used to respectively collimate the camera axis and two faces of a base cube. Then, through aiming at each other, a measurement network was built. Finally, the posture of the camera was measured. The error analysis and measurement experiments showed that the precision can reach 6″. This method has been used in the assembly of satellite GF-2 with satisfactory results.
During the development of the Lunar Rover, a posture tracking measurement scheme was designed to verify its movement control ability and path planning performance. The principle is based on the indoor GPS measurement system. Four iGPS transmitters were set around the test site. By tracking the positions of four receivers that were installed on the rover, the position and orientation of the rover can be acquired in real time. The rotation matrix and translation vector from the Lunar Rover coordinate system to the test site coordinate system were calculated by using the software. The measurement precision reached 0.25mm in the range of 30m2. The real time position and posture datum of the rover was overlaid onto 3-D terrain map of the test site. The trajectory of the rover was displayed, and the time-displacement curve, time-velocity curve, time-acceleration curve were analyzed. The rover’s performances were verified.