用于复杂管道内表面喷涂的冗余机器人轨迹避障规划

Trajectory Planning of Redundant Robot for Painting Inner Surface of Complex Duct Considering Obstacle Avoidance

本文旨在系统地解决长臂冗余机器人喷涂复杂管道内表面的避障问题.首先基于空间插值提出在线碰撞检测方法,该方法不仅适用于不同形状的管道,而且检测精度随着模型采样密度的增加而增加.机器人末端连杆位姿由目标点位姿约束确定,不能通过机器人的冗余自由度进行避障调节.针对喷涂机器人末端必然碰撞情况,提出放宽目标点姿态约束的方法,利用碰撞检测确定末端最快避障方向,计算最小姿态变化矩阵,达到该情况下的避障要求.同时利用管道虚拟轴线与各关节最快避障方向优化冗余机器人其他关节的避障能力.喷涂复杂管道内表面的仿真实验验证了本文方法的有效性,解决了机器人末端必然碰撞问题,优化了机器人的避障能力.与现有方法相比,该方法可以处理更为复杂的管道避障问题.

This research aims to systematically solve the obstacle avoidance problem of the long-arm redundant robot painting the inner surface of complex ducts.Firstly,an online collision detection method is proposed based on spatial interpolation.The method is universal for different shapes of ducts,and the accuracy increases with the sample density.Because the position and posture of the robot end link is determined by constraints of the goal position and posture.The obstacle avoidance of end link cannot be performed by redundant degrees of robot.As for inevitable end collision,a method of relaxing the target point attitude constraint is proposed.The collision avoidance direction is used to determine the fastest escape direction of robot end link,and the minimum posture change matrix is calculated for satisfying obstacle avoidance requirements.At the same time,the obstacle avoidance ability of other joints of the redundant robot is optimized,by proposing a optimization algorithm based on the virtual axis of the duct and the fastest escape direction of each joint.The simulation results of the inner surface painting of complex duct verify the effectiveness of the proposed method,solving inevitable end collision problem and improving obstacle avoidance ability of the robot.Compared with the existing methods,the method can deal with the obstacle avoidance problems in more complicated ducts.