Dynamic Simulation Research Of Space Rope Net Collision And Closing

Space net is a new on orbit capture technology,which is used to capture space debris to alleviate the increasingly tense space environmental problems.Because of the complex nonlinear behavior of space net,dynamic modeling and simulation of space net is of great significance.At present,scholars at home and abroad mostly focus on the development process of space net,this paper mainly focuses on the dynamic simulation of the collision and closure process of space net,the effect of the spin of target on the collision process and the effect of the closing velocity on the closing process are discussed in detail.Firstly,the key components of space net system are designed,including the launching mechanism,the net and the closing mechanism,especially,a new closure mechanism based on the principle of pyrotechnics is designed,and compared with the traditional mechanical energy storage closure mechanism and electric closure mechanism.The launching process of the net is tested to verify the rationality of the launching mechanism and the design of the parameters of the net.For evaluating the collision and closure process of space net,the evaluation indexes of space net collision and closure performance are put forward respectively.Secondly,the dynamic model of the net is established based on the truss element,and the correctness of the finite element simulation method is verified by comparing with the simulation of the launching process of the net based on the lumped-mass method.At the same time,the folding problem of the net in the finite element modeling is solved,and the simulation process of deployment of the net from the folding state is realized.In addition,the numerical calculation method of contact impact and its calculation process in the finite element program are described,and the solution process of display dynamics is summarized.Then,the collision between the net and the spinning dynamic target is studied.Based on ABAQUS/explicit module,the nonlinear finite element method is used to establish the finite element simulation model of the collision between space net and capture target,and the net collision simulation analysis is focused on the spinning target under different working conditions.The simulation results show that the spin of the target has little effect on the velocity and displacement of the target in the collision process;the larger spin angular velocity of the target is,the instantaneous collision force is greater,the rebound phenomenon of the mesh area is more remarkable,and the spinning and winding phenomenon of the net is more serious.Finally,based on the collision simulation model,the closure simulation model of space net and capture target is established,and the closing problems under different conditions of closing speed and target spin are studied.The simulation results show that the closing process can significantly accelerate the contraction of the net port and promote the wrapping of the net to the target.The larger the closing speed is,the closer the mesh opening is,and the better the closing effect is.However,the higher the closing speed is,the greater the peak tension of the closing rope is.In addition,the closing process is also effective for capturing large spin targets,which can effectively close the net port.At the same time,the ground closing test is carried out for the pyrotechnics closing mechanism.The test results show that the scheme of the pyrotechnics closing mechanism is reasonable and has the advantages of sufficient closing capacity,high triggering and good closing synchronization.