基于偏置补偿的6自由度腕部偏置机器人逆解算法

Inverse Kinematics Algorithm for 6-DOF Robots with Offset Wrist Based on Offset Compensation

串联6自由度腕部偏置机器人一般没有实用的封闭形式位置逆解.根据几何特征分析,以对应的腕部无偏置机器人的封闭解为基础,通过对腕部偏置量的平移补偿和对手腕位置点坐标的迭代修正,得到了腕部偏置机器人位置逆解的数值解.算法保证了末端姿态的正确性.根据末端位置精度要求控制迭代次数,可以得到任意精度的位置逆解.逆解过程中各关节变量的计算采用腕部无偏置机器人的封闭解,使得程序具有通用性.大量的数据试验表明,该算法可以满足实时控制要求.

Generally,there are no practical closed-form inverse kinematics solutions for 6-DOF serial robot manipulators with offset wrist.According to the geometric characters of the wrist offsets,based on the corresponding spherical wrist manipulator,numerical solutions for the manipulators with offset wrist can be obtained by complementally translating and iteratively correcting its wrist position.The algorithm does not affect the end orientation.Position errors are directly used to control the iterative process,so the numerical solutions can be evaluated to arbitrary precision.In the process,all joint variables are always computed by using the closed-form solutions of the corresponding spherical wrist manipulator,thus the codes are versatile.A large number of tests confirms that the algorithm can meet the requirements of real-time control.