Research On Mechanical Modeling And Experimental For Pulsed Detumbling Of Large Space Debris

With the development of the aerospace industry,more and more large space debris such as the final stage of rockets and failed satellites are trapped in space,which seriously threatens the reliability and safety of spacecraft in orbit.It is imperative to develop space debris active removal technology.The key lies in the implementation of on-orbit capture.However,large space debris has the characteristics of large mass,high-speed free rolling and unknown inertial characteristics and geometric dimensions,which limits the development of on-orbit operations of capture methods such as small robotic arms,flying nets,and flying claws.The premise of space debris capture is detumbling,the process of providing external control torque to attenuate the angular velocity of the target.In this paper,aiming at the problem of rapid attenuation under complex rolling motion of large non-cooperative targets,a non-cooperative impact force model considering non-linear factors is established,and the dynamic behavior of non-cooperative targets under non-ideal impact is analyzed.The design of the impact tip and the study of the detumbling method provide theoretical guidance.The mechanical pulse-type active detumbling method is adopted to comprehensively refer to the mechanical installation size and structural strength,and the optimal design of the variable pressure flexible impact terminal is developed.Considering the fluid-structure coupling effect in the tip,the nonlinear change of the stiffness of the flexible tip was analyzed by finite element simulation,and the working threshold of the tip pressure was determined.The LS-DYNA virtual prototype was used to analyze the strain and stress at the end during mechanical shock.A non-linear contact model for collision between flexible ends and space debris is established.The normal collision force calculation formula is derived based on the Hertzian contact theory.Considering the special friction characteristics of rubber materials,the nonlinear friction coefficient between friction pairs is analyzed based on energy conservation to obtain the cut Formula for calculating the frictional force.According to the conservation of momentum,in the free state,the motion state is divided into two types: uniaxial motion and triaxial motion according to the residual kinetic energy concentration of space debris.The research status of the space mechanism simulation device has been fully investigated.The five-degree-of-freedom air-floating platform simulates the movement of space debris.By using Euler angles to describe the transformation relationship,the moment in the centroid coordinate system is transformed into the robot arm coordinate system,and the final detumbling attenuation angular velocity is calculated through integration to obtain the impact distance of the robot arm.Through the statistical analysis of a large number of experimental data,the accuracy of the mechanical pulse detumbling force calculation model was verified.Combined with the experimental results,the friction force calculation formula caused by the structural deformation during the friction process was summarized and the friction calculation model was modified.The dynamic model of the air-floating platform is established,and the ground simulation verification test is carried out.Further,the manipulator and the internal pressure are controlled to apply a detumbling moment,and the motion parameters of the space debris are calculated and simulated by MATLAB programming simulation.Simulation experiments show that the design of the flexible end-effector is reasonable.As the impact torque increases,the detumbling efficiency increases.