基於Linapod平行機構之六維運動量測裝置

Six-DOFs Motion Measurement Device Based on Linapod Parallel Kinematics

陳柏綸

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(2012年)

摘要

本論文以Linapod平行機構為基礎，設計並實現一個六維運動量測裝置。此裝置包含上、下兩平板以及六根固定長度之連接桿。其中下平板上有六個球接頭，上平板上則有六組滑動接頭，滑動接頭上裝有球接頭與下平板之球接頭以連接桿相連。此六維運動量測裝置安裝於工具機上時，上平板裝於主軸端，下平板固定於工作平台上。機台驅動床台時帶動平板移動，再透過連接桿改變滑動接頭上球接頭位置並以線性光學尺回授之。量測系統藉由回授之球接頭位置配合平行機構轉換可計算出上平板相對與下平板之位置與指向關係，此六維關係再經過轉換可得到工具機刀具端相對工件端之位移與轉動關係，達到直接量測工具機六維運動誤差之目的。

研究中將提出Linapod平行機構之機構轉換方法以及其工作空間計算方法，並考慮實作的條件，選擇適當的機構參數來設計Linapod六維運動量測裝置。在裝置機構參數不能受環境溫度以及機器震動影響的考量下設計適當的安裝介面使量測裝置能安裝於機台上，最後將此Linapod平行機構實作出來。實作出之六維運動量測裝置在經過適當的起始化程序，配合以C語言撰寫之量測系統，可得到刀具相對於工件的六維運動關係，完成以Linapod平行機構作為六維運動量測裝置的目標。

關鍵字

Linapod平行機構 ； 六維運動量測裝置 ； 工具機運動誤差 ； 量測系統

並列摘要

This thesis presents a six-DOFs motion measurement device based on Linapod parallel kinematics, which composes of one top platform, one base platform and six link rods having constant length. The top platform is fixed with the main spindle and the base platform is mounted on the work table. The platforms are connected by six link rods with two ball joints at both ends of each link rod. When the work tables of the machine tool move, the platforms are driven by the main spindle or the work table. As a result, the ball bearing sockets on the linear guide way of the top platform are driven by the link rods. By measuring the position of the sockets, the relative position and orientation between the platforms can be derived, which also represent the relationship between the cutting tool and the work piece.

並列關鍵字

Linapod ； parallel kinematics ； machine tools ； measurement system

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