廠內自動搬運車之標記定向系統

Fiducial Mark-Based Orientation System for AGV in Factory Environment

李冠樺(Kwan-Hua Lee)

指導教授 ： 林巍聳

國立臺灣大學/電機資訊學院/電機工程學研究所/碩士(2013年)

https://doi.org/10.6342/NTU.2013.02037

摘要

工廠的廠房、電力設備和鐵製器材會擾亂全球衛星定位信號、無線電信號和磁場，本論文提出標記定向導航系統使自動搬運車可以在充斥干擾信號的廠內環境工作，標記定向導航系統採用機器視覺讀取平面二維條碼標記物，取得位置和方向的校正數據，自動搬運車便可以用沿途校正的輪軸慣性導航系統達成準確的導航。標記物佈置在工廠的地面上，作為電子地圖和實地的校準點，因此，自動搬運車的路線規劃和多量車的調度都可以在主控電腦進行。平面二維條碼標記物是針對廠內應用環境的新穎設計，本設計不採用人工特徵識別，而是用採用自然特徵演算法達成快速的辨識標記和精準的估計三維姿態，同時保證良好的背景分割效果，以及對遮蔽和光源變化的忍受度。此標記定向導航系統安裝在一台實驗用的自動搬運車上，從各種測試路線和不同環境條件下所得到的實驗數據，顯示連續行進情況下的定位和定向準確度都可以符合實際的工廠應用需求，也可以在主控電腦上規劃或變更行進路線。

關鍵字

自動搬運車 ； 基準標記系統 ； QR碼 ； 加速強健特徵 ； 遮蔽免疫 ； 電子地圖 ； 路徑追隨

並列摘要

The roof, power facilities, and iron equipments of the indoor factory will block and interfere the GPS, radio signal, and magnetic field. This thesis proposes a fiducial mark-based positioning and guidance system that can navigate AGV around the factory under high environmental disturbances. Planar 2D bar-code markers provide ground truth information. With the aid of bar-code markers, the navigation system can combine odometer as one of a part to achieve precise navigation. Bar-code markers are set on the floor to be the calibration points of factory and e-map, so the user can do path planning and multi-AGV monitoring by only using monitoring computer. The proposed bar-code marker is a novel design, especially suits for factory-like environment. The pattern and the detection algorithm of bar-code markers were introduced natural features (SURF), which promise good background segmentation, light immunity, occlusion immunity, and precise pose estimation. The fiducial mark-based positioning and guidance system were installed on an experimental AGV for actual testing. The result under different course and testing environment shows that our system’s real time positioning and orienting accuracy can fulfill actual factory implementation requirement, in addition. The course can be set or changed under monitoring computer.

並列關鍵字

Automated guided vehicle ； fiducial systems ； QR code ； speed up robust feature ； occlussion resilience ； electric map ； path tracking

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