Sensefly’s eBee unmanned aerial vehicle (UAV) is a fixed wing system which can be used for taking highly accurate aerial images at high resolution. Post-flight processing gives the client a final orthorectified photomosaic of the area under study, as well as creating a 3d point cloud and mesh which can be used in the 3d modelling of the landscape. Commonly useful surveying outputs such as a digital surface model and a digital terrain model are also possible, as is the creation of fly-through videos.
Positional accuracies of around 10-15cm are common, but these can be significantly reduced by the use of ground control points, which are additionally surveyed in by dGPS. Final resolutions of images can be in the order of 2-3cm per pixel.
The UAV system is extremely portable and is, therefore, ideal for work in remote locations. Its light airframe and battery technology means that flights of 45 minutes can usually be achieved, maximising the survey areas that can be covered in one flight. This area is only restricted by our legal obligations under the Air Navigation Order.
The UAV can carry a payload that either takes conventional RGB digital photos, or takes images across a range of specific wavelengths, such as the near infrared, which can be used to monitor the health of vegetation. Use of biological indices based upon this multispectral data extends the capabilities of the facility beyond traditional surveying into agronomy, environmental science, and archaeology.
Since the data is georeferenced, they are totally compatible with GIS systems for spatial analysis and map making. The facility also has the GIS expertise and software which will render survey data in the formats needed by clients.
No survey which gains ‘valuable consideration’ can be done without permission from the Civil Aviation Authority. The University holds a current permission for aerial work, has full insurance, and retains two CAA approved, BNUC-S qualified UAV pilots for the present provision.