工业机器人奇异规避轨迹规划方法

Singular Avoidance Trajectory Planning Method for Industrial Robot

针对激光追踪仪测量工业机器人定位误差测量中出现的六轴机器人运动学奇异问题,提出了奇异区域预测及实时优化的奇异规避轨迹规划方法。以国产配天AIR50-A机器人为研究对象,建立六自由度串联机器人运动学模型,解算机器人笛卡尔空间与关节空间映射关系。基于雅克比矩阵与奇异位形的关系模型,分析和预测机器人运动轨迹中存在的奇异区域。当机器人末端处于奇异区域或奇异预测域时,记录初始关节角序列作为奇异区域轨迹规划输入,利用五次多项式插值方法迭代更新奇异区域内的轨迹路径,机器人既定的运动路径与更新后的奇异规避路径结合形成机器人新的规划轨迹路径,保证机器人关节角运动学参数连续性的同时,规避奇异区域。实验结果表明,提出的奇异预测域及实时优化的奇异规避轨迹规划方法,能够抑制机械臂奇异区域附近关节角速度的激变,减少奇异位形对机器人运动性能的影响。

A singular avoidance trajectory planning method based on singular prediction domain and real-time optimization is proposed aiming at the kinematics singular problems during the measurement of six-axis industrial robot positioning error using laser tracer.A 6-DoF serial robot model is established using a domestic industrial robot PeiTian AIR50-A as the research object,thus the relationship is mapped between Cartesian space and robotic joint space.Based on the relationship model between Jacobian matrix and singular configuration,the singular regions in the robot trajectory are analyzed and predicted.When the end of the robot is in the singular region or singular prediction region,the initial joint angle sequence is recorded as the input of the singular avoidance trajectory planning,then the trajectory path in the singular region is iteratively updated by the quintic polynomial interpolation method.A new trajectory is formed by the established path combined with the updated singular avoidance path,which ensures the continuity of the kinematic parameters of the robot joint angle and avoids the singular region at the same time.The experimental results show that the proposed singular prediction domain and real-time optimized singular avoidance trajectory planning method can suppress the sudden change of joint angular velocity near the singular region of the robot and reduce the influence of singular configuration on the motion performance of the robot.