| Space net is an important method to capture high orbit non-cooperative target,which can adapt to different targets,also reduce the detection,recognition and racemic requirements.In This paper,the dynamic modeling and simulation of the space net on draging target is studied.The main contents include the following parts:(1)The flexible ropes have been used to a variety of space junk clean-up programs in recently.The dynamic modeling theory,method and spatial experiment progress of space net are studied.The importance and necessity of studying the drag dynamics of space net was clarity.(2)The flexible cable model was obtained based on the absolute node coordinate formulation(ANCF),and the dynamic model of space net was established.The research shows that ANCF is more suitable for the model of flexible net system with large deformation.(3)The equivalent bag dynamics model of the space net is established based on the ANCF,which reflected the contact collision continuously between space net and the target.Spacecraft dynamics model was established based on the mass point moment of Momentum and Euler equation.In order to describe the aircraft draging process,dynamic modeling of the combination was obtained.(4)The space net structure of square and cube frame is given.And the evaluation index of flying net draging performance was proposed.The evaluation index consists of the collision force of rope and the target,the spin angular velocity of the target,the displacement and velocity of the target.All of this can evaluate different program.(5)The simulation about draging the targets of different spin angular velocity and drag the target at different velocity is down.The effect of target spin and draging velocity was studied.Dynamics simulation results show that larger target spin angular velocity will cause serious winding of the rope-net and excessive speed may cause the target structure be destroyed.The target spin angular velocity should be monitored and adjust the drag velocity scientifically.(6)In order to adjust the rope tension of draging process,spring was gained between powered spacecraft and the target.The combination model of drag process is simplified to improve computational efficiency.The simulation only consider powered spacecraft,the rope of towing and target.Dynamic simulation shows that the spring can adjust the pulling force of the tow rope effectively.Also combined with powered spacecraft thrust control,the tension of the rope can take the initiative to adjust the process towing.This research can provide a reference for the future space towing mission. |
