Assembly precision prediction method for spacecraft based on 3D model

Aiming at the problem of assembly precision prediction for spacecraft, a new method based on 3D model was proposed. By summarizing the features of spacecraft assembly, the integrated assembly tolerance information model including assembly model, part model, structure model and tolerance model was constructed. Based on the construction of 3D model coordinate system, the tolerance variation effects of critical assembly node along with the tolerance variation transformation among different coordinate systems were analyzed. With the use of minimum deviation path, the deviation propagation path of spacecraft assembly was obtained and the prediction of the assembly precision was implemented by using extreme value method. Results from the tests on spacecraft section docking and equipment installation validated this new approach.