基于双机器人协调焊接标定算法

针对双机器人协调焊接任务,对双机器人工具坐标系（TCF）及基坐标系的标定进行研究,提出一种利用四元数法进行位姿坐标表示的工具标定算法以及"基于公共靶标的三点两步法"的双机器人基坐标系标定方案.根据向量的旋转理论,推导出四元数与旋转矩阵的对应转换关系,简化了TCF标定计算.将标定获得的两初始旋转矩阵差值的F-范数作为优化目标函数,利用拉格朗日乘数法进行优化求解,获得双机器人标定的精确值.最后采用上述标定策略进行了TCF标定及双机器人标定试验.结果表明,该方法可有效减少标定误差、提高标定精度.

Study of calibration algorithm based on dual-robot coordinate welding

The calibration method of TCF and base frame of dual-robot were studied based on the task of dual-robot coordinate welding. A calibration algorithm was proposed by using quaternion to represent the coordinates of the position and orientation, so was the base calibration system calibration project of dual-robot on the basis of the method of"three point and two-steps based on the public target". The TCF calibration calculation was simplified because of the transformational relation between rotation matrix and quaternion which was inferred according to the theory of vector rotation. Two initial rotation matrix differential value of F-norm obtained by calibration was served as optimized objective function, the precise value of calibration was obtained by using Lagrange multiplier method. At last, the tests of TCF and dual-robot calibration were implemented by the calibration strategy mentioned above. Experimental results showed that the accuracy of calibration was improved and the error of calibration was decreased effectively.