Research On Key Technologies Of Integrative Flexible Joint Of Dynamically Tuned Gyroscopes

This dissertation, based on the eleventh 5-year explorative project 'research of precision maching techniques of flexible structural component used in satellite' (project code: 02413180901003, supported by China Aerospace Science and Technology Corporation, is a special exploration for the integrative flexible joint.The integrative flexible joint is made of a block of elastic material. It is unlike the combinative joint which is assembled of an inner joint and an outer joint. And that its inherent 2-gimbal configuration removes the drifting error caused by 2N angular vibration. Therefore, it is a perfect upgrading product of the combinative one. But the research of the integrative joint is still in start-up stage in the country. The dissertation has systemically and deeply studied the integrative flexible joint. As a result, the key technologies of the integrative joint such as design, manufacturing and test have been resolved basically.The "flutter" motion and the "dynamic tuning" principle of the joint are analyzed by using dynamics theory of rigid body within mechanics of Newton. The differential equations of motion and error factors of the joint are presented.The analytical expressions of tension (compression) stiffness, torsion stiffness, bend stiffness and rotation precision of the joint flexure are educed by using variable cross-section continuous beam theory and Castigliano's second theorem. Moreover, the conception of the effective angle zone is put forward for the first time. Thus the basic theory of the mechanical characters of integrative joint is founded systemically and also validated by simulation of finite element analysis (FEA).A mended Back Propagation-Genetic Algorithm (BP-GA) strategy, which integrates merits of neural network (NN) and genetic algorithm (GA), is developed to resolve multi-variable and multi-objective problem of structure optimization. The nonlinear global mapping relation between design variables of flexure and volume, angular stiffness of flexure is established by building a BP network whose sample set is obtained by FEA and analytical computation. This mapping relation is further used...