Dynamics And Stability For Deployment Of Tethered Satellite System

Tethered satellite system refers to a new type of space system that connects two or more spacecrafts together with tethers.It has important engineering prospects in the aerospace.However,even the simplest tethered spacecraft system still involves complex nonlinear dynamic phenomenon and control issues.Deployment process is the most critical in entire mission,and on-orbit missions may terminate due to the failure of deployment.Therefore,it is necessary to study the dynamic response and impact when the tethered system is out of control.At the same time,it is also necessary to study tethered spacecraft deployment control law,ejection deployment device and ground experiment.The research on these items will do a lot of help to improve the stability of tethered satellite system technology and increase success rate of satellite missions,which lays a sturdy foundation for the practical application of space technology research results.This paper mainly studies tethered spacecraft system.The research content is as follows:1.The Lagrange equation is used to establish mechanical model of the space tethered system,and the elasticity and damping of the tether are considered.The dynamic response of the deployment is analyzed,as well as the influence of system parameters and initial state on the impact when the system is out of control.Finally,global analysis of impact force is performed.2.The study analyzes two kinds of tethered system control laws respectively with open-loop and closed-loop.The analysis of linear feedback control is performed and the reasonable engineering application domains are given,as well as stability is proved.Then,the GUI interface for the deployment of tethered system is designed.3.A small ejection deployment device is designed for the satellite simulator deployment process in ground experiments.It has the functions of ejecting separation,cutting the tether,controlling tension and buffering,meanwhile it also has a simple structure and stable performance.4.The microgravity environment in space is simulated by air flotation method,and the space dynamics equation is equivalent to that on the ground test platform.The self-made ejection deployment device is used to perform ground experiments on the dynamic behavior of the tethered system.