傾斜攝影測量在三維建模精度之研究

A Study on the Accuracy of 3D Modeling Using Oblique Photogrammetry

本研究分4項實驗,使用Matrice 300 RTK無人機搭載睿鉑D2M相機，於宜蘭大學校園內進行探討。共設有10個控制點、20個檢核點，使用iTwin Capture Modeler進行建模。針對無人飛行載具（Unmanned Aerial Vehicle，UAV）探討在相同航高及前後重疊率條件下，側像重疊率分別為40%、60%及80%時的三維建模精度及成果差異；其次，對垂直攝影與傾斜攝影生成的三維模型進行比較，以評估不同攝影方式對建模結果的影響；此外，也探討了控制點分佈及地面解析度（Ground Sample Distance，GSD）對於建模成果及其精度的影響。研究結果為確定傾斜攝影技術在三維城市建模中的實際精度，並提出優化建模過程的參數設置，以提高模型的實用性和可靠性，並對未來城市規劃和管理實務具有重要的意義。
實驗結果：側向重疊率越高，模型精度越高，以80%側向重疊率最佳；傾斜影像建模精度優於垂直影像，能更好還原建物外部細節，但在針對正射影像品質有較高要求的應用場景中，單鏡頭垂直拍攝可能是更好的選擇；高樓層設置合理控制點及較小GSD並降低飛行高度可提升模型精度。

This study is divided into four experiments, using a Matrice 300 RTK UAV equipped with a Riegl D2M camera, conducted within the National Ilan University campus. A total of 10 control points and 20 checkpoints were established, and 3D modeling was carried out using iTwin Capture Modeler. The research focused on evaluating the accuracy and differences in 3D modeling results under the same flight altitude and forward overlap conditions, with side overlap rates of 40%, 60%, and 80%. In addition, comparisons were made between 3D models generated from vertical photogrammetry and oblique photogrammetry to assess the impact of different imaging approaches on modeling results. Furthermore, the study examined the effects of control point distribution and ground sampling distance (GSD) on the accuracy and quality of the generated models. The findings aim to determine the actual accuracy of oblique photogrammetry in 3D urban modeling and to propose optimized parameter settings for improving the practicality and reliability of models, providing valuable insights for future urban planning and management practices.
Experimental Results: A higher side overlap rate leads to higher model accuracy, with 80% side overlap producing the best results. Oblique imagery yielded better modeling accuracy than vertical imagery, offering superior reconstruction of building exterior details. However, for applications with stricter requirements on orthophoto quality, single-lens vertical photography may be a more suitable option. Additionally, setting control points appropriately at higher elevations, using a smaller GSD, and lowering flight altitude can improve model accuracy.