Drones are becoming increasingly common on construction sites, used for a variety of reasons.
While in the past they may have been used for fairly basic site monitoring or photography, technological advances are making drone surveying techniques more sophisticated.
One such example can be seen in the field of ecology, a less well-publicised part of construction projects, but one that is often a crucial stage in enabling a scheme to get off the ground.
Specialist consultant Thomson Ecology has been partnering drones with its own TIM mapping technology to map habitats and topography.
The drone provides clear aerial photography (see video) which is then overlaid with habitat mapping to allow clients to track changes to habitats over a period of time.
The project shown here was undertaken for Essex & Suffolk Water, with the team mapping more than 269 ha in two blocks of land across Norfolk, including Trinity Broads and Burgh Common.
Thomson Ecology senior GIS analyst Neil Smith says that the team first has to identify if there are any constraints such as restricted airspace, which clearly wasn’t an issue on this survey in Norfolk.
With the survey carried out in mid-winter, the team had to wait for a window of good weather – but once they had it, the flight went ahead without a hitch.
“For surveys like this, the actual flights are very simple and mainly consist of identifying the areas to be flown and establishing an appropriate flight height, speed and pattern,” he says. “Autonomous systems within the UAV deal with a lot of the flight handling and control, while the pilot and other members of the flight team monitor the progress of the flight and watch out for any potential incursions into the flight area both on the ground and in the air.
“Because of the large size of the survey area, this process was repeated many times over the course of a week.
“An extra complication arose from the occasional need to launch and land the UAV from a boat. When surveying the more extensive areas of water, we realised that the most efficient method was to use the boat for access, and as a mobile platform for the survey flights.
The team collected more than 4,500 still images from the flights, which were then stitched together to form a single geo-referenced image for each survey area.
The project gave Essex & Suffolk Water valuable information on the habitats that surround its reservoirs and water treatment works, all of which are subject to ongoing maintenance – with the information provided by the drone mapping also easy to share with other stakeholders.
It shows the power of new technology to act as an enabler for the infrastructure industry, providing more accurate information and helping improve efficiency.