Dynamics Parameter Identification And Control Of Space Robot

Accompanied China’s space increasing exploration activities, the space robotwill play an important role in the establishment and maintenance of the space station,satellite recovery, arrest, release. when manufacturing of space robot, Due toprocessing, assembly errors and in-orbit tasks fuel consumption, as well as captureunknown target, the corresponding dynamic parameters of space robot have to causevariation. But precise dynamic parameters will be indispensable for path planning,dynamic control and robot body attitude control on space robot. So the identificationof the dynamic parameters is a key technology.Unlike ground robots, space environment of the space robot remain complexand special and maintain conservation of angular momentum on space robot system.In this paper，identification model is established base on angular momentumprinciple, and unknown dynamic parameters are respectively identified with leastsquares and constrained genetic algorithm. Offline identification does not requirecomplex calculations, only need to measure the changes in value of the angularmomentum with the reaction flywheel, joint angle. To verify identification principle,two plane system are adopted, the results basically meet the actual needs, but thegenetic algorithm is much better than the least squares. In addition, this paperproposed identification method based on joint torque. Mathematical model ofparameter identification are established base on the Newton-Euler recursivedynamics of joint torque by comparing the least squares and the Gauss-Newtoniterative identification methods. In this paper, Simulink recognition system ofsimulation is applied including planning, control, identification algorithm andthree-dimensional models, and the recognition of the results showed that the latter ismore ideal.In space activities, the movement of the robot arm control, dynamics and forcecontrol is also crucial to space perform space rendezvous and docking, rail assemblyand maintenance tasks. Contrasting PD, computed torque and adaptive fuzzy PIDcontrol with designing simulation control system of the Simulink, the results showthat the fuzzy control is better than the first two controls when running response andtrajectory tracking. It is unavoidable that space robot contact with the externalenvironment in space, so the contact forces and moments can not be ignoredimportant part, and the force control essential. This paper studies the space robotshared compliance control to explore the hybrid control of force and position.Combined with the ground experiment system, experiment carry out the lines andcurves of the robot compliance control exercise test, as the result, the experimental results are satisfied.