Stabilization Control Of Space Robots After Target-capture

With the growing number of human space activities,the demand and the difficulty for on-orbit capture missions is increasing,and the requirements for stability in the capture process are received more attention.After the space robot completes the capture of the target,they turn into a combination by a rigid connection with the change of their dynamic characteristics,resulting in the fail that the original control parameters meet the performance requirements,the unstable motion of the space robot and even the damage to the hardware and software systems.Therefore,the study on stabilization control of the space robot after capturing targets has important theoretical and practical significance.The main content of this research is as follows:Firstly,the modeling and stabilization control of the combination depending on known target kinetic parameters is proposed.The dynamics model without load is established,the system state of the space robot and the target before and after the capture is analyzed,and the new dynamic parameters of end of effector after forming connection between the end of effector and the target are derived.The stabilization control method of the combination for controllable base is put forward to realize the stabilization control of the space robot after the target capture is completed.Secondly,considering the influence of the flexible effect of the arms on the space robot after capturing the target,the stabilization control of the combination considering the flexibility of the arms is proposed.The dynamics model of the combination considering the flexibility of the arms is established,the initial state of the combination is analyzed and the dynamic equations are decomposed and reduced.A compound control method of stabilization control considering the flexibility is put forward to achieve the stability of the base attitude and the vibration suppression of the flexible arms.Then,the stabilization control of the combined system by unknown dynamic parameters of the target is proposed.An adaptive control method for the combination based on the inaccurate parameters of the target is put forward to achieve the stabilization control.An identification method of dynamics parameter of the target is designed to realize the acquisition of the target dynamic parameters,where the dynamic parameter identification equation is deduced,and the excitation trajectory is designed.Finally,the experiment on the stabilization of space robots after target-capture is carried out.The platform of the experiment for space robots was constructed,and the experiment program for stabilization control of the combination considering the flexibility was designed.By analyzing the results,the correctness and effectiveness of the methods are verified.