Research On Collision Dynamics And Stability Of Space Manipulator

In the future space activities,many space operations need to be completed,and space manipulator will play an important role.The space borne manipulator is a kind of manipulator which is carried on the small man-made celestial body.Compared with the large manipulator,it has the advantages of low fuel consumption,long service life and low operation cost.Therefore,it is of great theoretical and practical significance to study the dynamics and the related collision stability of the space borne manipulator.The most commonly used method to solve the dynamics problem of space borne manipulator system is to use the second Lagrange equation to establish the dynamics equations.In this paper,the dynamic equations of the general space borne manipulator system are derived by using the second Lagrange equation.Then,the dynamic simulation models of the two DOF Manipulator System are established in ADAMS and MATLAB.The simulation results show that the dynamic model is correct.Collision problem widely exists in the production and life practice,and has always been an important problem in the engineering application research.The same is true for the onboard manipulator system.In this paper,with the aid of Adams dynamic simulation software,the end collision characteristics of the space borne manipulator system are studied from the perspective of engineering test.The virtual prototype of the system is built in the software,and the collision process is simulated by using the control variable method.Then,the experimental data is processed and analyzed by MATLAB,which is the reference for the collision problem of the system in practical application.In order to keep the system stable,the stability of the system should be considered in the system design.In this paper,the stability of a space borne manipulator system under external forces is discussed in two typical cases.When the joint is locked,a theoretical model of the external force related to the center of mass of the system is given by using the theory of rigid body in theoretical mechanics.On this basis,the angle of the external force at the end with the smallest angular displacement is given.In the case of uncontrolled joints,a dynamic model including damping suppression at joints is established.According to the actual needs and expected accuracy requirements,the appropriate evaluation index is selected and the appropriate damping coefficient is determined to minimize the impact of collision on the base.