AutoCAD介面平台於機械手臂之動態變速度避障路徑規劃與應用

The Design and Application for the Dynamical Obstacle- Avoidance With Variable Speed Path planning of Robot by Using AutoCAD Interface Platform

呂聰池(Tsung-chih Lu)

指導教授 ： 洪永銘

國立臺北科技大學/機電學院/機電整合研究所/碩士(2005年)

https://doi.org/10.6841/NTUT.2005.00020

摘要

目前一般機械手臂之路徑規劃方法，大部分都是以人工教導之方式寫入移動點座標值，作為機械手臂移動時之路徑規劃方式。但是在變速度運動之障礙物的路徑規劃，及複雜的工作狀態中，教導盒的功能是無法滿足實際需求，因而無法將可能發生之問題於事先給予正確解決，以致於浪費較多的工時。
本研究主要係以電腦輔助設計軟體Auto CAD 2004版本為發展之環境，以其內建之VBA程式語言為基礎，並搭配三菱公司所出產之RV-E2型六軸多關節式機械手臂，及菱華PCI-8132控制卡所驅動之輸送帶，研發撰寫出一套適用於變速度下動態避障路徑規劃之人機介面，可以讓使用者於離線之工作環境下事先規劃出機械手臂與工作物件之運動路徑。
使用者在Auto CAD環境中，於規劃完成之人機介面內，輸入障礙物基本資料，例如起點座標、形狀尺寸及不同位置之移動速度，以及機械手臂運動速度、手臂（夾爪）外型尺寸和起點及終點等相關資訊，將障礙物與手臂之3D實體模型予以建立，並利用其GetBoundingBox指令功能來取得矩形邊界點的最大值與最小值來做為機械手臂預定到達之避障點的計算參考，計算避障點與機械手臂的移動起始點之距離，並與機械手臂實際之移動距離加以比較，以找出一條最短之避障路徑。
再將避障路徑資料經計算處理後，透過RS-232傳輸至機械手臂的控制器及輸送帶控制器分別予以驅動。實驗結果顯示，本方法確實可以在障礙物於不同之速度及位置條件狀況下，做好路徑規劃的工作。
機械手臂在現今工業上之應用範圍非常廣泛，且有愈來愈廣為使用的趨勢，而本方法之研究將可利用於工業上同期移送或非同期移送之不同零組件之組裝線上機械手臂的避障動作，及自由流輸送帶上物件移載時機械手臂避障工作。
本研究的方法，可以做好彈性組裝最佳化的工作。將機械手臂的起點、終點位置規劃為零件供料處及零件組合工作站，治具的移送規劃為障礙物的移動。如此一來，實際的生產中，可以根據不同的供料點及工作站及完成的循環時間，而規劃機械手臂的避障路徑及障礙物的速度。在路徑可變，供料位置、工作站位置及移動速度可變的條件下，所規劃的生產方式，可以完全應付多樣少量的生產方式，同時離線時的規劃方式可以縮短停機及重新教導的時間。因此本研究方法可用於彈性組裝系統上的最佳化的生產方式，對於工業上多變及複雜的生產方式將提供很大的幫助。

關鍵字

機械手臂 ； AutoCAD ； 動態規劃 ； 障礙物 ； 路徑規劃 ； 同期移送 ； 非同期移送

並列摘要

At present, general method to define the route of a robot is by using a teaching box to fix the coordinates of each point en route. But under the changing speed condition, to avoid the possible obstacles en route, it is hard to accomplish satisfactory results by a teaching box only. Due to the limited functions of a teaching box, this will result in time-wasting and also getting inaccurate prediction of hindrance en route of robot movement.

In this research, the writer wishes to use AutoCAD 2004 as basis and through its VBA and 3D programming and drawing function , using a combination of the Model RV-E2 of Mitsubishi 6-joints Robot and the conveyor controlled by ADLINK PCI-8132 to develop a system to define settings of the robot movement within an interface to avoid obstacles under changing velocities. Such a system should be able to determine the safe route in off-line working conditions.

The operator of the robot, under the AutoCAD environment, may input the basic data of obstacles to the man-machine interface - such as the starting point coordinates, the dimensions of the obstacle and its movement, and also the movements of the robot arm - in such details of the grip’s shape, dimensions, velocities, starting point and destination, to establish a 3D solid model. With those data, the operator can determine the possible shortest route of the robot movement by help of the Get Bounding Box Command to realize the rectangular margin of Maximum and Minimum values,

When the resulted shortest route is produced, the data will be sent to the controller of the robot through RS-232 communication cable, and also to the conveyor’s controller through communication cable. This experiment shows satisfactory results using Obstacle-Avoidance for the robot path planning.

The robots are used widely in the modern industries. The robots will be used more and more in the future. A study of this kind will have great merits both in synchronized and non-synchronized combination of robots and conveyors in Obstacle-Avoidance planning. If one can determine on off-line basis, of the movement of robot to avoid any obstacles en route, it can help to increase the productivity of the working lines, and saving the time consumed in planning.

並列關鍵字

Robot ； AutoCAD ； Theory of intelligent graph interference ； Path planning ； Obstacle-Avoidance ； Synchronized transfer ； Non-Synchronized transfer

參考文獻

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