五軸加工即時碰撞偵測之研究

Research On Real-Time Collision Detection for Five-Axis machining

顏嘉亮(Jia-Liang Yan)

指導教授 ： 林榮信

國立中正大學/工學院/機械工程學系/碩士(2012年)

摘要

本研究主要目的在於發展五軸CNC工具機即時碰撞偵測技術，研究方法包括機台型式分析、運動學分析、G-Code加工指令插補分析及各軸碰撞偵測演算法效率提升分析。本研究碰撞偵測應用分離軸定理檢測各軸間的STL三角網格干涉行為來偵測是否發生碰撞。
本研究主要貢獻在於提出分離軸插補演算法，並配合三角網格篩檢、工具機型式分析來節省運算時間並提升碰撞偵測效率，本研究成果顯示比一般碰撞偵測方法可提升效率達80%。本研究成果應用於簡化工作台傾斜型五軸工具機為例，平均每次偵測碰撞時間約為4msec，最長時間為6.7msec。證明本研究演算法可以適用於一般CNC，並控制在10msec限制下之即時防碰撞偵測。

關鍵字

分離軸 ； 碰撞偵測

並列摘要

The main goal for this research is to develop a methodology on real-time collision detection for five-axis CNC machining system. The research method includes machine configuration type analysis, machine kinematics analysis, machining g-code interpolation analysis, and axial collision-detection algorithm efficiency improvement analysis. In order to detect if the objects are collided with each others, this research applies separating axis theorem to detect the interference among the axial triangular meshes.
The main contributions for this research are proposing the separating axis interpolation algorithm, and cooperating with the mesh rearrangement and machine configuration analysis that improves collision detection efficiency and reduces the computation load. The result shows that the proposed method improves 80% efficiency on computation load, comparing to conventional collision detection methods. Applying the research achievement on a simplified table-tilted type five-axis machine tool, the average computing time for each completed collision-detection cycle is around 4 msec. and the maximum computing time is 6.7 msec. This result illustrates that the proposed algorithm fits for real-time application on common CNC controllers, which require the servo-control sampling time below 10 msec.

並列關鍵字

collision detection ； separating axis

參考文獻

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