The inflatable space antenna is gradually used in various spacecrafts because it is portable and foldaway. It is usually made of thin-film materials and has a flexible surface, so that measuring force is not tolerable in measurement process. Close-range photogrammetry is considered as an optimal solution because of its advantages of non-contact operation and fast data acquisition. To improve measuring precision, a method combining bundle adjustment algorithm and the distance constraint is presented in the paper. Two experiments under different conditions are accomplished and experiment results are compared. One experiment is completed with the distance constraint and another without. The experiment results are compared by two parameters: tightness and residuals. The measured object is an inflatable antenna with a 3.5-m diameter.

This paper presents a method to measure the deformation of large deployable mesh microwave antenna by using the photogrammetric technology. Because the mesh reflector surface is controlled by 79 nodes, measuring 3D coordinates of these nodes accurately is the key to test the deformation of antenna. The technique of camera calibration, the matching method of the image points, and the solution of measuring 3D points are introduced in this paper. The experimental data is also provided. This paper proposes a method to calculate the spatial coordinates of microwave antenna nodes by using the bundle adjustment with distance constraints. This method is capable of correcting the influences of the lens distortion and improving system measurement accuracy. In reference to the fact that the surface of this antenna is controlled by 79 nodes, and the design parameter of these nodes is already known, a method based on digital surface model constrain is used to solve the image points matching problem. This method efficiently simplifies the computation procedure and shortens the measurement time.