Research On Dynamic Obstacle Avoidance Motion Planning Of Manipulator

With the diversified and complex application scenarios of manipulator,the control requirements of industrial manipulator are gradually improved.Due to the complex working space of the manipulator and the presence of irregular or dynamic obstacles,it interferes with the execution of tasks of the manipulator.In response to the above problems,the path planning and trajectory planning of the manipulator under the scene of dynamic obstacles are studied in this dissertation.The main research contents of this dissertation are as follows:(1)An improved particle swarm optimization algorithm based on sine and cosine functions is proposed to solve the problem of complex inverse kinematics solving process and non-unique solution of the manipulator.The inverse kinematics solution is designed by adding sine cosine function to the particle swarm algorithm.Since the particle swarm algorithm has the characteristics of global search and iterative optimization,the inverse kinematics solution method based on the transformation matrix between the end effector and the base coordinate system is simple and effective.A multi-objective optimization function is designed as the fitness function of the algorithm to ensure the uniqueness of the inverse kinematics solution.Finally,numerical simulation is given to verify the effectiveness of the algorithm.(2)Aiming at the problem of path planning in dynamic workspace of manipulator,a dynamic obstacle avoidance path planning algorithm based on improved reverse rapidly exploring random tree is proposed.Through the alternation strategy of environment detection cycle and motion planning cycle,the manipulator adjusts its motion path in real time in dynamic working environment.In the motion planning cycle,a new path is planned reversely from the target point to the current path point to avoid obstacles.The idea of gravity and dynamic step adjustment are added to rapidly exploring random tree algorithm to make the manipulator search the collision free path quickly in the workspace.Simulation results show the effectiveness of the algorithm.(3)A multi-objective trajectory planning method based on genetic algorithm is proposed to solve the local obstacle avoidance problem of manipulator.The cubic spline interpolation function is used to connect the discrete path points to achieve the requirement of smooth motion trajectory.The interpolation method of intermediate points is adopted in the obstacle avoidance strategy of the manipulator,and the genetic algorithm is used to optimize the two interpolation points to adjust the local trajectory.The multi-objective fitness function is designed as the optimization objective to solve the trajectory performance optimization problem of the manipulator.Finally,the effectiveness of the algorithm is verified by the simulation of the manipulator.