Drone data and 3D maps tackle road safety at Gotthard Mountain Pass
Surveyors at pixmap took full advantage of the unique features of the WingtraOne to achieve high-quality video and 3D maps needed by IMPULS AG to annually monitor erosion.
The Gotthard Pass is a famous roadway connecting northern and southern Switzerland. An important road for countless motorists, the pass is vulnerable to rock falls due to erosion along the mountain. It features rocky terrain in the middle of the Swiss Alps with an elevation of up to 2350 m (7710 ft) above sea level (ASL).
In the spring of 2018, a federal agency overseeing road conditions, Bundesamt für Strassen ASTRA, asked a Swiss engineering firm specializing in natural hazards analysis, IMPULS AG, to monitor erosion along the road. IMPULS hired drone services specialist pixmap, which uses the WingtraOne for its photogrammetry-related projects. WingtraOne’s tailsitter VTOL, terrain following feature and robust drone mapping features met the demands of the results-oriented Swiss engineering team on a tight schedule.
- Land change monitoring, Road monitoring
- Switzerland
The combination of Wingtra’s vertical take-off and landing (VTOL) and its terrain following feature made this mission possible.
Reto Weiss
CEO, pixmap
One day of flying for a year of road safety
To identify the quality and position of rocks through aerial imagery, pixmap flew WingtraOne with its Sony QX1 payload featuring a Voigtländer lens. The wide angle of this lens allowed for high-quality 3D reconstruction. The survey took several weeks, of which only one day was spent flying. It covered 48 ha (118.6 acres) along the “Gotthard Strasse” mountain road pass and involved 460 images at a resolution of 6 cm (2.36 in), with an absolute locational accuracy of around 1 m (3.28 ft).
The data collected by WingtraOne allowed pixmap to create a 3D model with 6 cm accuracy that IMPULS AG’s engineers now use to locate points of interest. They simply zoom in on parts of the image map to inspect rocks. If any rocks look unstable, IMPULS AG will inspect them on-site. By comparing surveys each year, the engineers will be able to identify and study any changes that might indicate a rock fall and take action to prevent it.
Drone-based monitoring of natural hazards provides an efficient decision-making basis for further on-site analysis. Thanks to a cloud-based inspection tool, the data can easily be made available and used by different stakeholders.
Reto Weiss
CEO, pixmap
