改进人工势场法的机械臂避障路径规划

Improved Artificial Potential Field Method for Robotic Arm Obstacle Avoidance Path Planning

针对人工势场法在机械臂避障路径规划中易陷入局部最小值等问题,提出一种改进人工势场法的机械臂避障路径规划方法。首先,对机械臂连杆及障碍物进行包络体建模,将避障碰撞检测问题转化为圆柱体与球体、圆柱体与长方体的最短距离求解;其次,提出在机械臂关节空间建立目标点的引力场和斥力场,在笛卡尔空间建立引力场相结合的算法,并采用快速随机搜索树法(RRT)解决传统人工势场法局部极小点的问题;最后,采用MATLAB开展仿真与实验,结果表明该算法规划目标位置平均误差为0.010 m,相较于传统的算法更接近于目标位置,可实现机械臂逃离局部极小点并完成避障路径规划。

Aiming at the problem that the artificial potential field method is easy to fall into a local minimum in the obstacle avoidance path planning of robotic arm,this paper proposes an improved artificial potential field method for the obstacle avoidance path planning of robotic arm.Firstly,the envelope of the manipulator′s connecting rod and obstacles was modelled,and the obstacle avoidance collision detection problem was transformed into solving the shortest distance between the cylinder and sphere,cylinder and cuboid.Secondly,an algorithm combining the gravitational field and repulsive field of the target point in the joint space of the manipulator and the gravitational field in the Cartesian space is proposed,and the fast random search tree method(RRT)is used to solve the problem of local minima of the traditional artificial potential field method.Finally,MATLAB is used to carry out simulations and experiments.The results show that the average error of the proposed algorithm is 0.010 m,which is closer to the target position than the traditional algorithm and can realize the robot arm to escape from the local minimum and complete the obstacle avoidance path planning.