Last week EasyUAV did a test to see if UAV could become in indispensable tool for Land Surveyors. We required detailed measurements that engineers would accept to base their designs and costing’s on. We teamed up with Mondo Cané Precision Surveys who did the ground control and post processing. The flight altitude was set at 100m AGL, the UAV spent about 4mins in the air and here’s what we found:
The resolution according to the model was an average of 0.87 pixels. @ 27 mm per pixel.The model was scanned at 1 meter intervals forming a grid of 30 000 points and a scan of 5 meter intervals forming a grid of 2500 points, both scans showed a very good result. The latter was used as test data and the scanned points were within 1-4cm of the control points. The 3 dimensional model could be used to select single points (edge of road and drains etc). The height of low vegetation was derived from difference between model triangulated points of the vegetation and the visible ground points and these differences were applied to the final model.
Under normal circumstances the whole survey would have been resolved in terms of processing in less than an hour. The verdict: We managed to deliver 2500 scanned points with an average accuracy of 1-4cm in just under two hours. That included taking 15 GPS based ground control points (35min), the UAV flight (4min) and the post processing (80min) – and incredible result!