Accurate collaborative positioning by dual robots is crucial for achieving high precision in dual-robot mirror milling operations. However, the tool frames constructed in conventional dual-robot coordinate calibration approaches need to be substituted by a new set designated for the mirror milling, which may induce a notable reduction of collaborative positioning accuracy. This paper presents a novel collaborative coordinate calibration technique designed explicitly for the dual-robot mirror milling system with a measurement module, avoiding the need for subsequent tool frame replacement for mirror milling. The proposed method starts from designing a multi-probe ultrasonic measurement module on the mirror milling system's supporting head and developing an online workpiece pose identification technique by using the ultrasonic measurement. A specially designed mirror milling test is then implemented to correlate the dual-robot collaborative pose information with the pose daviation observed between the machined and ideal design features. By identifying the machined feature's pose, we realize a high-precision dual-robot coordinate calibration approach that ideally suites for the dual-robot mirror milling system equipped with a measurement module. The effectiveness and advantage of proposed method has been validated through a set of comparative experiments. Experiment results show that the proposed method obviously outperforms the benchmarking dual-robot coordinate calibration method reliant on laser tracker technology.

中文翻译：

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基于铣削测试的带测量模块的双机器人镜面铣削系统坐标标定方法


双机器人精确协作定位对于实现双机器人镜面铣削加工的高精度至关重要。然而，传统双机器人坐标标定方法中构建的工具架需要被专门用于镜面铣削的新工具架所取代，这可能会导致协作定位精度显着降低。本文提出了一种专门为带有测量模块的双机器人镜面铣削系统设计的新型协作坐标校准技术，避免了镜面铣削后续更换工具架的需要。该方法首先在镜面铣削系统支撑头上设计多探头超声测量模块，并利用超声测量开发在线工件位姿识别技术。然后实施专门设计的镜面铣削测试，将双机器人协作位姿信息与加工特征和理想设计特征之间观察到的位姿偏差相关联。通过识别加工特征的位姿，我们实现了高精度双机器人坐标校准方法，非常适合配备测量模块的双机器人镜面铣削系统。通过一组对比实验验证了所提方法的有效性和优点。实验结果表明，该方法明显优于依赖激光跟踪技术的基准双机器人坐标标定方法。