以自率光束法提升四旋翼UAV航拍影像之空三平差精度

Using Self-Calibration to Promote the Aerotriangulation Accuracy of Images Aquired from a Quadrotor UAV

謝幸宜(Hsing-Yi Hsieh) ； 邱式鴻(Shih-Hong Chio)

《航測及遙測學刊》 16卷4期 (2013/01) Pp. 245-260

https://doi.org/10.6574/JPRS.2013.16(4).2

摘要

整合GPS、INS的無人飛行載具UAV（Unmanned Aerial Vehicle）可安全、快速地蒐集資料。然UAV系統常搭載非量測型像機取像，以一般航測方式執行空三平差時，將使平差結果產生較大誤差。自率光束法空三平差可將影像坐標的系統誤差模式化、並加以改正，提升空三平差精度。本文中以四旋翼UAV系統搭載非量測型像機獲取影像，於空三平差作業時比較以：（1）光束法空三平差、（2）自率光束法空三平差、以及（3）預改正的自率光束法空三平差的平差結果。結果顯示：預改正的自率光束法空三平差結果最佳，以Brown（1976）附加參數模式的自率光束法空三平差精度次之，且均優於光束法空三平差精度。

關鍵字

四旋翼 ； 無人飛行載具 ； 非量測型像機 ； 自率光束法

並列摘要

Unmanned aerial vehicles (UAVs) integrating with GPS and INS provide a safe and fast method for data acquisition. The UAVs which can implement automatic pilot promote the automation of data collection. In UAV systems, the GPS antenna and the INS system are not aligned with the perspective center, so that the GPS and INS records should be revised according to the geometry of UAV systems for exterior orientation references. And the cameras equipped with UAVs are often belonging to the non-metric camera, whose interior orientation parameters can be acquired by close-range photogrammetry softwares. However, there are several different camera models used in the softwares and the interior parameters calibrated by different softwares would not be the same, so that the interior parameters of the non-metric camera should not be regard as constant in aerotriangulation. Self-calibration can not only calibrate the camera in close-range photogrammetry but also model and compensate the departures from collinearity in aerotriangulation to promote the positioning accuracy. This study uses the images acquired from a safe UAV system, a Quadrotor UAV, and compares the results by using different aerotriangulation procedures. In this paper, the optimal accuracy can be obtained by using self-calibration in bundle adjustment with all measurements been pre-corrected for radial and decentering lens distortion. And the suboptumal accuracy can be obtained by using Brown's (1976) added parameters in bundle adjustment, better than the results of using bundle adjustment. But using Ebner's (1976) added parameters in bundle adjustment cannot help promoting the positioning accuracy.

並列關鍵字

Quadrotor ； UAV ； Non-metric Camera ； Self-calibration