使用雷射遮斷感測器之機械手臂設備定位校正技術

Abstract

定位設備是機器人工具中心點在空間中註冊與環境和工件相對位置的重要設備，當機器手臂為了因應不同工作而裝載不同工具時，能夠計算出工具施作點的新位置進行新任務。然而商用的校正設備除了價格不菲、設置昂貴，更換場域使用時也受制於廠商的技術服務項目。有鑑於此，本論文開發了一個以簡易遮斷式十字雷射感測器為基礎、用以校正定位設備的演算法。該十字雷射有四個自由度，通過一系列指定的機器人與雷射感測器運動、以及感測器觀察到的開關信號，可以估測出雷射感測器坐標系相對於已知機器人坐標系的相對旋轉和平移、並且作為伴隨產物計算出工具中心點相對手臂端點的位移。該演算法先在虛擬環境中對一工業用六軸串聯式機器人進行模擬測試，之後在硬體上進行實驗驗證，能夠達到 0.07 mm的精度。

The positioning device is an important equipment in the robotic tool center point that registers the relative position of the environment and workpieces in space, when the robotic arm is required to accommodate different tasks by mounting different tools, it is capable of calculating the new position of the tool's working point for performing a new task, however, commercial calibration equipment is not only expensive in terms of price and requires costly setup, but also its usage in different settings is limited by the technical service offerings provided by the manufacturers. In view of this, this thesis presents an algorithm based on a simple interruption cross-laser sensor to calibrate positioning equipment, the cross-laser sensor has four degrees of freedom, through a sequence of predetermined movements of the robot and laser sensor as well as the switch signals observed by the sensor, it enables the estimation of the relative rotation and translation between the coordinate system of the laser sensor and the known robot coordinate system, furthermore, it calculates the displacement of the tool center point relative to the end-effect of the robotic arm as an accompanying result. The algorithm is initially tested through simulation on an industrial six-axis serial robot in a virtual environment and subsequently validated through experimental tests on the hardware, it achieves an accuracy of 0.07 mm.