Summary: | The use of aircraft in the field of topographic mapping is not exactly a new but rather it has been main method in topographic map production since the early 20th century. Commonly known by the name, photogrammetry - this method relies on the camera for an aerial image acquisition that is sited on the piloted aircraft platform. Nowadays, much attention has been given to the use of Unmanned Aerial Vehicles (UAV), which has become a popular platform especially for the purpose of large-scale topographic mapping. Therefore, this research focuses on the potential of Fixed Wing UAV as an aerial image acquisition platform to produce photogrammetric products such as Digital Terrain Model (DTM) and Orthophoto for large-scale topographic mapping. Correspondingly, all relevant aspects are taken into account starting from the flight planning, aerial photography, camera calibration, camera settings, Ground Control Points (GCP) distribution, and data processing up to the accuracy standard of the mapping product generation. The research area for this study are Cameron Highlands, Pahang and UiTM Arau, Perlis Campus. Photo control and verification points are determined by GPS (Global Positioning System) surveying method. The image processing for the purpose of DTM and Orthophoto generation are establish using Agisoft™ software, assisted by ArcMap™ and Topcon Tool™ software. Results show that flight plan that consists of camera calibration process, camera configuration settings, flying altitude, percentage of image overlap and location of control point are the major factors for mapping product accuracy using this method. Assessment of mapping products found that mapping accuracy is within the standard tolerance as set by the American Society of Photogrammetry and Remote Sensing (ASPRS) which in average are in sub-meter with square root mean error (RMSE) for the planimetric coordinates (northing, easting) and hypsometric (elevation) are ± 0.300 meter, and ± 0.400 meter respectively. This also proves that digital images taken using compact digital camera from fixed wing UAV platform is capable of generating good and accurate mapping products.
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