Research Of Obstacle Avoidance Path Planning Based On Manipulator With Six Degrees Of Freedom

Obstacle avoidance path planning technology for manipulator is one of the core contents for intelligent mobile robot research. Manipulator obstacle avoidance path planning is the manipulator in work environment of obstacles can search out a safe collision-free optimal or suboptimal path which is from the origin to the destination and guarantee a certain performance indicators, according to the given instructions and the environmental information. It is mainly to solve the following three questions:firstly, making the manipulator complete the movement from the the start point to the destination point; secondly, using a certain algorithm to make the manipulator can hypass the obstacles; finally, optimizing the manipulator trajectory under the conditions of completing the above tasks.In this thesis, obstacle avoidance path planning for the PUMA560manipulator with six degrees of freedom is studied from the following three aspects:the modeling of the manipulator, the collision detection between the manipulator and obstacles, and the manipulator path planning algorithm. Firstly, the manipulator kinematics related theories are introduced. The position and orientation, the D-H model and kinematic equations are studied deeply. The, on the basis of the D-H model for PUMA560manipulator, the equations of the positive kinematic and the inverse kinematic are solved. After analyzing the advantages and the disadvantages of collision detection model such as bounding sphere, AABB, OBB and k-Dops, the bounding sphere is chosed for the detection of obstacles in the space environment. Finally, the artificial potential field path planning algorithm based on A*algorithm is proposed, after analyzing the artificial potential field method and the A*algorithm. By using the A*algorithm to improve the artificial potential field method, an optimized obstacle avoidance path is planning which avoid to falling into local minimum. According to the path points of obstacle avoidance path planning, the manipulator can calculate the corresponding joint angle, and move to the appropriate position and orientation. Thus the manipulator can successfully avoid obstacles to reach the specified destination point. The artificial potential field path planning algorithm based on the A*algorithm is simulated, which is used for the PUMA560manipulator with six degrees of freedom. Through the experiments of no collision and collision, the manipulator path planning is achieved quickly and efficiently by the algorithm. The expected goal of this thesis is reached.