Simulation Model Establishment And Trajectory Planning Of Space Manipulator Based On Finite Element Analysis

In recent years,with the continuous improvement of Aerospace Science and technology in various countries,more and more space missions need to be completed by space manipulator.Due to the structural characteristics of light weight and long arm,the flexible vibration problem is relatively prominent,which has a great impact on the stability of the system.In this paper,the simulation model of space manipulator is established by using the finite element analysis method.The active control method of space manipulator is studied,and the trajectory planning algorithm is studied.The simulation based on the ANSYS Workbench platform verifies the validity of the model.The main contents of this paper are as follows:First of all,this paper introduces the research status of domestic and foreign scholars in the field of space manipulator.This paper discusses the modeling analysis and control system design method of space manipulator,and introduces the research results of trajectory planning of space manipulator.Secondly,the kinematic model of the manipulator system is established by using geometric method and D-H parameter method.By solving the Jacobian matrix,the relationship between the end velocity and joint velocity of the manipulator is established.Lagrange method is used to complete the dynamic modeling of manipulator system,and the relationship between moment and joint state variables is established.Thirdly,the simulation model of single degree of freedom manipulator system is established based on the ANSYS Workbench finite element simulation platform.The validity of the model is verified by modal analysis and instantaneous dynamics simulation.At the end of the manipulator,a mass point is applied to analyze the modal frequency and mode shape when the system grabs different weight loads.Active control methods such as PD control,differential advance PD control and variable gain control are studied and verified on the ANSYS platform.On this basis,the simulation model of the two degree of freedom manipulator system is established to verify the effectiveness of the control effect and model establishment.Finally,the trajectory planning method of space manipulator is studied.The research includes joint space quintic polynomial interpolation,trapezoid velocity interpolation,Cartesian space point-to-point trajectory planning.It is verified on the ANSYS finite element simulation model.For free floating space manipulator,the minimum trajectory planning method of base disturbance is studied.