利用地面三維雷射掃描儀取代傳統千分之一數值地形測繪之研究─以竹東下員山地區為例

Abstract

地面三維雷射掃描儀應用的技術歷經長久的發展已逐漸成熟且運用範圍日廣，尤其在現今使用地面三維雷射掃描的點雲及影像作為數值地形圖測的繪製及自我檢核的依據，也使得在展現三維場景或城市模型成果時越來越能表達真實的感覺。依靠地面三維雷射掃描儀外業掃描的點雲資料及相機影像，提供給內業人員繪製數值地形圖，如何得到一個圖資內容完整及精度在容許範圍內的千分之一數值地形圖便成為一個重要的研究課題。 研究方法利用一、人工現場施測、內業電腦計算輔以測繪軟體半自動連線，以人工繪圖編修為主；二、以地面三維雷射掃描儀施測、內業以人工輔以套裝軟體做點雲拼接組成一個專案，專案交由繪圖人員做認點連線，後專案結合交由專人做圖層圖例編修。使上述兩者同區域成果重疊，分析其施測內容、繪製點位之精度差值、施測及內業作業時間。 本研究選定竹東下員山一處面積約2公頃，以傳統方式測繪及以地面三維雷射掃描儀測繪，比較其作業流程、時間、及圖面精度，分析以三維雷射掃描儀取代傳統千分之一數值地形測繪之可行性。

The technical applications of ground-based 3D laser scanner are getting mature and widely used after a long-last development. Particularly, the point clouds and images from the ground-based 3D laser scanner are used for generating numerical graphical mapping and self-assessment, which make the 3D scenery modeling and the city model more accurate. Although the indoor draftsman can plot the numerical graphical map according to the point clouds and images, it is still a research issue that how to derive a numerical graphical map with complete map content and 1/1000 accuracy. The research method is as follows. First, perform on-site manual measurement, office work computer calculation with semi-automatic software and manual edit. Second, obtain measurements from ground-based 3D laser scanner, manually combine the point clouds as a project via software packages, perform some of drawing, with the line and point by drafting crew, then edit the graph layer and legend by experts. We overlap the partial results of both methods, analyze the measure the content、draw the precision of the position、total time of the work. The research is performed on a two-hectare site of Jhudong Township Siayuanshan. The measurement was performed by traditional method as well as ground-based 3D laser scanner. We compared the operation flow, time, and graph accuracy, and evaluate the feasibility of replacing the traditional method with the ground-based 3D laser scanner.