Research On Obstacle Avoidance Path And Trajectory Planning For Six-dof Manipulator

Path planning and trajectory planning are hot and crucial issues of robot control.They are the combination of artificial intelligence and robotics.Obstacle avoidance path planning for manipulator is to plan a path from the starting point to the ending point without any collision.Trajectory planning is to plan the position,velocity and acceleration of each joint in the motion process.They have very important significance for manipulators to complete tasks correctly and safely.In this paper,the obstacle avoidance path planning algorithm and time optimal planning are studied based on IRB120 six axis robot.The main work and research results are as follows:(1)The D-H parameter method and screw method are used to set up the kinematics model and solve the forward and inverse kinematics.An example was given to verify the consistency of the two methods.(2)According to the kinematics model,the workspace is analyzed,and the boundary points of the workspace are extracted.(3)In the obstacle avoidance path planning,the artificial potential field method and the HS(harmony search)algorithm are studied,and the improved methods are put forward.In view of the defects of traditional artificial potential field method,a variable step size method is proposed.Firstly,a big step is used to determine the intermediate point,which divides the search path into two parts.Then a small step is used to search the two parts respectively.For HS algorithm,through the improvement of the harmony memory initialization and the formation of the new harmony,a new path planning algorithm is proposed based on the improved HS algorithm.Based on MATLAB and Adams,the proposed algorithm is verified by simulation.(4)According to the obstacle avoidance path planning in the case of single obstacle,the particle swarm optimization algorithm is used to optimize the trajectory in the joint space,and the validity of the proposed method is verified by simulation results.