Multi-body Dynamics Analysis Of Tetrahedral Deployable Antenna Mechanism

With the application and development of space satellite technology,space deployable antenna mechanism,as an important part of space satellite technology,has also been developed.Compared with other deployable antenna mechanisms,large spaceborne tetrahedral deployable antenna mechanism has been widely used because of its simple structure,high stiffness,modular splicing and small volume after folding.In this paper,the basic unit mechanism of tetrahedral deployable antenna mechanism is taken as the research object,and the kinematics modeling method of tetrahedral deployable antenna mechanism is studied.The rigid body dynamics and rigid-flexible coupling dynamics modeling and analysis of tetrahedral deployable antenna mechanism are carried out.The main research contents of this paper are as follows :Firstly,the kinematics modeling method of the deployable antenna mechanism is studied.Based on the absolute node coordinate method,the rigid body kinematics equation is derived.The kinematics models of the tetrahedral deployable antenna mechanism and the combined unit deployable antenna mechanism are established by using the derived rigid body kinematics equation.Adams software and Matlab software are used to simulate and calculate the kinematics models of the two antenna mechanisms.The correctness of theoretical derivation and modeling is verified.The characteristics of different kinematics modeling methods are introduced and compared.Secondly,based on the Lagrange method,the rigid body dynamics equation of the motor-driven tetrahedral deployable antenna mechanism is established.The rigid body dynamics equation is theoretically calculated by Matlab software.The virtual prototype model is established by Adams software and compared with the theoretical calculation results.The influence of different driving modes and motor positions on the rigid body dynamic characteristics of deployable antenna mechanism is studied.Finally,based on the absolute nodal coordinate method and the natural coordinate method,the mass matrix,the generalized external force matrix and the elastic force matrix of the rigid and flexible components are derived.On this basis,the rigid-flexible coupling dynamic equation of the tetrahedral deployable antenna mechanism is established.The theoretical calculation and simulation analysis are carried out by using Adams software and Matlab software,and the correctness of the theoretical modeling is verified.The different dynamic characteristics of rigid model and rigid-flexible coupling model are compared and analyzed.The influence of gravity and material parameters on the dynamic characteristics of rigid-flexible coupling model is studied.