Precise Aerial Surveying
Efficiency and Accuracy – Superior Technology and Know how
- very high, absolute accuracy < 3 cm X Y Z
- variable ground resolution (GSD) based on customer needs <1- 3 cm
- 3 X more accurate compared to RTK through PPK correction data
- no Ground Control Points required
- no need to hike the area
- maximum efficient: in the field , during processing
Unmanned aerial systems, especially multicopter-Systems with highly precise positioning in combination with high resolution metric and precise calibrated cameras enable the use of photogrammetric aerial surveying for countless applications. Being able to compute the precise position of every image point in the final result is the unbeatable advantage.
We utilize the most precise PPK-technology available on the market, which exactly determines the focal point of every single image, taken during the flight, in order to achieve the most accurate results without the need of ground control points.(GCPs). This is not only saving quite some time and money but also enables to perform surveys in areas where you either can not walk through like disposals, stockpiles of critical materials etc. In addition aerial surveys enable to measure points which cannot be surveyed from ground e.g. intersection of roofs and walls on the upper side of a building .(Ger: Wandhöhe)
Besides the significant reduction of time and effort in the field through the elimination of GCPs the computing time for photogrammetric data processing will be reduced. This increase in overall process speed results in very short overall project times. Based on the magnitude of the project the overall lead time form flight planning until the data set will be handed over to our customer could be from a few hours until just a few days.
Through utilization of the currently world wide most accurate GNSS positioning, methodology and our experience we are replacing GCPs by hundreds highly precise determined camera focal points, who take over the function of the GCPs. Besides the advantage to determine these positions up in the air free of any satellite shadows or interferences the PPK (post processed kinematics) technology offers a significant accuracy advantage over RTK (real time kinematics): The absolute error of the provided correction data (e.g. SAPOS in Germany) in the post processing system is in the order of 10 mm and 3x less than with ther real time service. Additionally, unlike with RTK systems we do not need any mobile network availability like LTE for receiving the correction data. We can work independently.
Our process for precise aerial surveying results:
Flight planning: Based on the requested image resolution (GSD), using a dedicated mission planning software, we calculate based on lots of parameters flight altitude, flight path of the drone, trigger positions, etc.
Automated flight The pre calculated waypoint route is transmitted via data link to the UAS, the drone gets launched and directly flies to its starting point. After the UAS has reached the first Waypoint the drone flights to the next waypoint at constant speed and triggers the camera as calculated, while the PPK system records every trigger event in the center of exposure with millisecond accuracy. Depending on the utilized UAS and the size of the area, the way point routes are divided into multiple segments in order to exchange batteries on time or the UAV recognizes a certain minimum battery level and returns automatically for changing batteries.
Alike a vertical plane, e.g. a facade or an entire building can be surveyed. The drone will be, as long it it reasonable automatically controlled by a way point plan or need to be operated manually.
Data processing: After the flight the recorded position data will be corrected by reference data acquired from available CORS or VRS network services e.g. SAPOS GPPS to achieve the highest accuracy possible. These highly accurate coordinates are then loaded into the photogrammetry software together with the photos. Images will be automatically aligned based on their reference coordinate data (better 3cm XYZ) and the calibration data provided for the relevant camera. The software detects 20,000 individually recognizable points in every image and will align other images by at least 5,000 of these points which can be clearly detected in 3 or more photos. Time consuming manual alignment of ground control points (GCPs) is not necessary any longer which also reduces the time for manual work as well as computing time! In the following process step, the software is computing from images, coordinates and the lens calibration data a dense three dimensional highly accurate point cloud.
This point cloud is the basis for any further computation in order to generate a wireframe 3D model, a digital elevation model (DEM) or an orthomosaic. Additionally any product (point cloud, DEM, orthomosaic) can be exported to be further processed in CAD or GIS applications. Additionally we offer digitization of the resulting ortho-views into precise CAD drawings.
To make a long story short: admost precision with mapping or inspecting your terrain, buildings or infrastructure resulting in maximum transparency and reliability for your project!. This is why we rely on reliable and proven technology , competency and renowned global partners in the GEO information business for you!
Let’s talk about your project and the options! We are looking forward to your call or your email! Pleas call us @ +49 (0)8104 8889810 an, or just use our Contact Form!