| Solar panel deployment mechanism（hereinafter referred to as "deployment mechanism"）is an important part of space exploration projects.After years of research and development,its technology is relatively mature,but the problem that the deployment mechanism cannot be successfully deployed after lift-off still occurs from time to time.Due to the particularity of the working environment,once the deployment mechanism fails,it will affect the completion of the deployment action,or lead to the failure of the space exploration mission.Both fault detection and troubleshooting need to pay a huge price.In view of the above problems,this thesis effectively improves the reliability of the movement function of the deployment mechanism through in-depth and systematic research on the model and method for the identification/repair of the assembly clearance design defects of the deployment mechanism.Based on Hertz elastic contact theory,the hinge model with clearance under dry friction and the hinge model with clearance under lubrication condition are constructed,and the kinematics and dynamics of the unfolding process are analyzed.Through the dynamic simulation of the unfolding process of the unfolding mechanism with different assembly clearance values,the hinge collision condition during the unfoldingprocess is obtained.The aim of the research is to minimize the collision force and the number of collision accumulations as much as possible,and obtain the optimal design of the assembly clearance.The aim is achieved,which realizes the identification and repair of the design defects of the assembly gap of the deployment mechanism under the condition of considering the influence of lubrication.Based on the environmental thermal analysis,the thermal deformation equation of the unfolding hinge is deduced.Through the simulation of the thermal deformation of the unfolding hinge in the working environment,the minimum value of the assembly clearance is determined;Based on the thermal deformation caused by friction heating,the thermal deformation of ball screw assembly is studied.Through the analysis of bearing thermal deformation caused by friction,the minimum clearance value to be met in bearing assembly is obtained;The thermal deformation of ball screw assembly is analyzed,and the minimum clearance value to be met in ball screw assembly is determined;The range of assembly clearance is reduced,and the identification and repair of assembly clearance design defects of deployment mechanism considering the influence of thermal deformation are realized.By analyzing the Cell-Domain-Body（CDB）information of each topology level of parts in CAD system,a method for identifying and repairing the assembly design defects of the deployment mechanism based on the redundant information constraint network is proposed.By improving the traditional constraint relation network,the operation objects in the assembly process are converted from parts to cells,new nodes are added to the constraint relation network,a dedicated information storage node is constructed for assembly constraint information,and redundant information is injected into the constraint relation network as a verification condition,an improved constraint relationship network for the deployment mechanism is constructed,which realizes the synchronization and coordination of assembly and verification in the process of assembly design.After the assembly design is completed,based on the improved constraint relation network,the assembly defects can be identified and repaired quickly,and the efficiency and accuracy of defect identification and repair of assembly design of the deployment mechanism is improved. |
