Research On Space Manipulator Assisted Docking Based On Impedance Control

With the development of China’s manned space program, the construction ofChina’s own space laboratory and space station systems are Chinese space exploration’sa crucial step. Especially after the Temple One’s rendezvous and docking is successfullycompleted, the construction of the space station seems even more imminent. Whenlaunching spacecraft and target spacecraft rendezvous and docking successfully, weneed transfer the launching spacecraft to other interface or assemble to a predeterminedposition, while leaving to the subsequent docking spacecraft the docking position. Herethe spacecraft moved to a predetermined position is called Translocation, aftertranslocation the launching spacecraft docking with the target spacecraft againsuccessfully called re-docking. During re-docking process, due to the spacecraft totransfer weight a significant dozens or even hundreds of tons, it is a large mass load.Furthermore strong systemic, and strong coupling between systems, but alsoconsidering the process of the Translocation and re-docking, spacecraft, targetspacecraft and auxiliary systems, such as the manipulator system’s influences andconstraints, technical difficulties are very huge.In this paper, under the background of construction and assembling of the spacestation with the use of manipulator, especially the process of translocation andre-docking. considering the minimal impact on the space station system, impedancecontrol method was proposed. First, progress at home and abroad is introduced intranslocation and re-docking, and summarizes the key issues in re-docking. Then basedon Newton-Euler recursive algorithm established seven DOF space manipulatordynamics model. In the follow according to the principles and characteristics ofimpedance control, impedance controller is designed and simplified. Using Matlab’sSIMULINK module controller model by two-link planar dynamics model is build,verification algorithm effect. Finally by combining the seven degrees of freedommanipulator dynamics model, controller model with dynamic model of the dockingmechanism, based on Adams and Matlab co-simulation to analyze the effect of auxiliarysecondary docking. Then based on an analysis of the effects to propose the controlwith Constant force in compare., but also consider the seven redundant degrees offreedom conformational change may be relatively large, thus making the six degrees offreedom manipulator impedance control, and six degrees of freedom manipulatorConstant force control. Meanwhile according to the project implementation,rationalization proposals are given in the six-dimensional force installation locationselection.