A Dual Quaternion-Based Approach for Coordinate Calibration of Dual Robots in Collaborative Motion
A Dual Quaternion-Based Approach for Coordinate Calibration of Dual Robots in Collaborative Motion
复制标题
基于双四元数的双机器人协作运动坐标标定方法
DOI：
10.1109/lra.2020.2988407
复制
发表时间：
2020-07-01
影响因子：
5.2
通讯作者：
Li, Miao
中科院分区：
文献类型：
--
作者：
Fu, Zhongtao;Pan, Jiabin;Li, Miao
坐标标定精度是实现双机器人协同运动、视觉定位的前提。在AXB=YCZ的情况下，需要确定相关的手眼（X）、机器人-机器人（Y）和工具-法兰（Z）坐标关系，以便为双机器人操纵提供准确的数据。旋转和平移分量的经典独立估计和可分离求解不可避免地会导致一定程度的不准确和不一致。为此，本文提出的工作描述了一种基于双四元数（DQ）的有效方法，用于校准与双机器人协作运动相对应的手眼（X）、机器人-机器人（Y）、工具-法兰（Z）变换。建立DQ形式的双机器人闭式运动方程后，标定过程分为两个步骤：1）手眼变换（X）标定，让带有视觉传感器的一个机器人自由移动，同时保持另一个带有末端工具的机器人固定配置，从而通过SVD求解基于DQ的线性方程来获得标定结果 算法; 2）将机器人-机器人（Y）和工具-法兰（Z）的同时标定转化为基于DQ的方程，以类似的方式得到结果。进行了仿真分析，考虑了噪声水平和不同数据对的存在，同时还进行了校准实验以验证所提出方法的准确性和有效性。
Coordinate calibration accuracy is a prerequisite for the achievement of collaborative motion of dual robots, and visual positioning. In the case of AXB=YCZ, the associated hand-eye (X), robot-robot (Y), and tool-flange (Z) coordinate relationships need to be determined in order to provide accurate data for dual-robot manipulation. The classical independent estimations and separable solving of rotational and translational components, inevitably induce certain levels of inaccuracy and inconsistency. To this end, the work presented herein describes an efficient approach based on dual quaternion (DQ), to the calibration of the hand-eye (X), robot-robot (Y), tool-flange (Z) transformations, corresponding to the dual-robot collaborative motion. After establishing a closed-form kinematic equation for dual robots in DQ form, the calibration process is divided into two steps: 1) the hand-eye transformation (X) calibration is performed by letting the one robot with the visual sensor move freely, while keeping the other robot with the end-tool in a fixed configuration, thereby allowing the calibration result to be obtained by solving the DQ-based linear equations with the SVD algorithm; 2) the simultaneous calibration of robot-robot (Y) and tool-flange (Z) is transformed into a DQ-based equation, and the results are obtained in a similar way. A simulation analysis is carried out, accounting for the presence of noise levels and different data pairs, while calibration experiments are also conducted to verify the accuracy and efficacy of the proposed method.