Research On Obstacle Avoidance Motion Planning Of Free-floating Space Robot Based On Sampling Algorithms

The development of space technology makes the application of space robots more extensive,especially the free-floating space robot with uncontrolled position and posture of space carrier in operation time.In this article,free-floating space robot is taken as the research object,and its simulation technology and sampling-based obstacle avoidance motion planning method are studied.The main research work of this article is as follows:Firstly,based on Moveit! And OMPL,a simulation platform for free-floating space robots is built.In the simulation platform,the virtual manipulator method is used to design the inverse kinematics solution plug-in for the space robot model with arbitrary structure,and the Runge-Kutta method is used to design the high-precision state recursive device for the free-floating space robot.Secondly,aiming at the problem that the current sampling-based obstacle avoidance motion planning algorithm for free-floating space robots can not optimize the path,the control-based sparse stable rapidly-exploring random tree(SST)is applied to free-floating space robots.Because of the asymptotic near-optimality SST provides,we can plan collision avoidance path and optimize it at the same time in the Cartesian space in which the position and posture of the end of the manipulator of space robot are located.Finally,aiming at the problem of low accuracy in obstacle avoidance motion planning of free-floating space robots based on sampling algorithm,geometry based rapidly exploring random tree(RRT)and inverse velocity kinematics of free-floating space robots are combined to carry out velocity-level motion planning in the Cartesian space in which the position and posture of the end of the manipulator of space robot are located.The method can plan high-precision path,and realize two kinds of obstacle avoidance motion planning,that is,the position and attitude of the end of the manipulator reach the target position at the same time and the position of the end of the manipulator reach the target position without disturbance to the space carrier.