直接姿態回授控制Delta 機器手臂研發

Development of a Direct Pose Feedback Controlled Delta Robot

高寶珩(Pao-Heng Kao)

指導教授 ： 雷衛台

國立清華大學/工學院/動力機械工程學系/碩士(2015年)

摘要

本論文利用實驗室發展多年的六維運動量測裝置(MMD)對Delta機器臂進行直接姿態量測回授控制研究。MMD可直接量測機器工具相對於工件的六維姿態，為將MMD安裝於Delta機器臂上，於研究中重新設計了MMD上板，以石英做為MMD上板材料降低熱誤差，並對新版的MMD進行誤差敏感度及工作空間分析。
在直接姿態回授控制方面，本論文嘗試了三種控制方法，分別為「直接觀測法」、「設定點偏移法」及「混合控制法」，其中「直接觀測法」的特徵是將MMD所量測到的工具位置經Delta機構逆轉換所得的馬達轉角取代編碼器所回傳的角度，「設定點偏移法」的特徵是將MMD所量測到的工具位置進行Delta機構逆轉換後與編碼器位置相減所得到的差值做為目標設定點偏移量，「混合控制法」則是將上述兩種方法依運動控制之狀態進行切換。本論文探討了在不同控制方法下直接姿態回授控制的特性，實驗結果顯示Delta機器臂在三種控制方法下於雷射定位以及動態循圓實驗中各有其特性，但皆能使運動精度大幅度升。

關鍵字

直接姿態回授控制 ； Delta 機械臂 ； 六維運動量測裝置

並列摘要

The aim of this thesis is to study the performance of a Delta robot using the Motion Measure Device (MMD) as the pose sensor for the direct feedback control. The MMD is a six degrees of freedom measuring device which can measure the relative pose between tool and the work piece. To install the MMD on Delta robot, a new quartz upper plate is designed. The error sensitivity and workspace of the MMD are analyzed in design process.
In direct pose feedback control using the MMD, three kinds of control methods are tested in the thesis. The first control method is “Direct Observation method”, which use the angle calculated by using the measured result from MMD for the Delta inverse kinematic transformation instead of the encoder. The second is the “Set Point Shift method”, which detects the difference between the angle calculated by using tool pose measured by the MMD for the Delta inverse kinematic transformation and the encoder values and use it as offset for setting point. The third is the “Hybrid Control method”, which switches between the mentioned methods in different situations. All three feedback control methods can enhance the positioning and motion accuracy dramatically.

並列關鍵字

Direct Pose Feedback Control ； Delta Robot ； MMD

參考文獻

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