The Research On Motion Planning In Self-assembly Of Space Cellular Robots

Space cellular robot is a type of intelligent operational equipment which is always used in aerospace field.Besides changing the structure of robot through moving its cells by itself.it can decide its own motion and structure when facing new environments,new tasks and damages caused by unsuspected strike.The space cellular robot which is researched in this article is composed of many independent cells,which are connected by the designed connecting mechanism.This article is mainly research the independent cell's control of connecting motions.The main contents include the algorithm of robots' clustering,self-connecting in the local scope,and global path planning.There will actually be many cells to complete the combination of expected structure,these cells which are not taking part in connection are doubtless obstacle.With the difficulty of obstacle detection of independent cells,coming up with an algorithm of support vector machine,which can outline many adjacent cells.So,we can change the obstacle of independent cells to the obstacle of a massive area,which can reduce the difficulty of obstacle detection and decrease the time loss.Dividing the space cellular robots' self-reconfiguration into two steps which are connecting each others locally and global path planning.During the stage of global path planning,designing the algorithm based on artificial potential field and probability randomly mapping.Considering of the very distribution of robots and barriers,picking up a function which is a repulsive force related to the distance between the moving cell and the obstacle.Finally,due to the situation of the terminal's area,leading the way of PRM in the algorithm.In the stage of locally connecting,Firstly,we design a algorithm within finite-state machine based on polar coordinate.So the cell is going to move following the arc path,which is more fitful than based on rectangular coordinate in terms of the particular motion structure and the infrared sensor's position of cells.Besides,according to the position and characters of infrared sensors,we can calculate the essential initial area of this step of the unitary motion.Through the study of related ways of path tracking,coming up with the target of global path planning.