Path Planning and Evaluation for Obstacle Avoidance of Manipulator Based on Improved Artificial Potential Field and Danger Field

This paper takes 6-DOF manipulator as the research object, proposes the improved Artificial Potential Field (APF) method to plan the obstacle avoidance path of the manipulator, and combines the Danger Field (DF) method to evaluate the safety of the path planned using APF. According to the characteristics of the manipulator, the kinematics model of the manipulator is analyzed, and the ball envelope algorithm is applied to simplify the physical model of the obstacle. Compared with the traditional APF method, the improved APF searches in the joint space and introduces the joint attraction potential to improve the search speed and accuracy. The problem of local minimum is dealt with by the combination of adding virtual obstacles and increasing joint attraction potential. The improved APF not only has the advantages of good real-time performance and smooth path, but also solves the problem of the traditional APF falling into a local minimum, and combines the danger field method to judge the path rationality to ensure no collision with obstacles. Through simulation verification, the proposed method realizes the obstacle avoidance path planning of the manipulator and the safety evaluation of the planned path.