Skeye BV conducted a project at the end of June in cooperation with our sister company Deep BV for the city council of Amsterdam. The aim of the project was to measure the water depths in a lake as well as the heights of several constructed spits that extend into the lake. Deep BV used a multibeam echosounder for the underwater measurements and Skeye used the Microdrone MD4-1000 unmanned multicopter for surveying the above water parts.
The unmanned multicopter flew at a height of 50 meters above the terrain and this resulted in an orthophoto mosaic with a resolution of just 1.2 cm. Over 20 ground control points were installed and measured using a high grade RTK GPS receiver. In addition an extra 65 points were measured randomly in the terrain so that quality checks could be performed.
The final delivered product was a combined digital elevation (depth) model of the terrain above and below the waterline.
The quality control showed that an average difference in height was obtained of just 23mm with a standard deviation of 14mm…