Drone surveys for construction and development

Queensland Drones specialises in professional GIS-grade UAV surveys and aerial mapping for building, construction and development projects.

In a market where most operators have no formal training and provide generic cloud-based ouputs with no real value and no real understanding of the havoc they can create for clients, Queensland Drones stands out with in-house professional photogrammetry delivered by post-graduate qualified GIS specialists. Our aerial mapping surveys use survey-grade ground control and industry-standard error management workflows to produce the best possible accuracy every time.

Our aerial photogrammetry service gathers georeferenced images for construction and development projects in a fast, efficient, safe and cost-effective way.   Compared to ground-based surveys, aerial mapping with drones can be 4-5 times faster and much safer. Compared to using conventional aerial photography, drone surveys are typically 80-90% cheaper and can provide accurate aerial mapping with centimetre-level RMSE precision.

As a professional aerial mapping company, we work with surveyors, architects, building designers and other professionals to provide a broad range of aerial survey mapping using drones including:

  • Drone surveys and mapping prior to commencement of construction
  • Identifying terrain and topographical mapping features
  • Creating mesh maps of existing buildings and structures
  • Elevation, contour and topographical surveys
  • Volumetric measurement of cut and fill areas
  • Mapping and analysis of vegetation on site and surrounding the site
  • Drone surveys and mapping after earthquakes, flooding and other disasters
  • Mapping of archeological and historical sites
  • Record of construction and development over time

We are not surveyors, but our precision UAV surveys ensure that architects, engineers, developers, surveyors and builders can use our drone mapping survey outputs to reduce both the time and cost of collecting accurate high-resolution data for large sites. We use precision Trimble satellite-based GNSS survey equipment to ensure precision placement of ground control points and our resident GIS specialist ensures accurate interpretation of geo-referenced data is translated into precise aerial mapping products.

Seen enough? Contact us now for an obligation-free discussion and quote for your construction or development survey needs.

Our aerial survey mapping outputs for building, construction and development professionals include:

Georeferenced Orthomosaic Image

Queensland Drones generates a high-resolution TIFF file for drone surveys created by stitching together hundreds of images captured in an aerial drone survey and levelling them based on precision ground control points captured in the aerial photogrammetric images. The TIFF file is georeferenced based on the GPS information in the ground control point files, not the data from the UAV images which can be inaccurate. We typically use a projection based on the WGS84 geographic coordinate system, but we can also use other projection systems if required.

Georeferenced 3D model of a construction site with precision ground control points from drone surveys

The geoTIFF orthomosaic image can be opened in GIS software like QGIC or ARCGIS and overlaid onto other spatial layers including satellite images and street maps. The GeoTIF can also be imported into AutoCAD using Civil 3D and used as background to design models.

Digital Surface Model – DEM, DSM or DTM

The point cloud developed through drone surveys to generate the orthomasaic image above can also be used to develop a digital elevation model (sometimes called a digital surface model or digital terrain model which normally includes removal of all elevated structures and vegetation) providing a topographical view of the survey area including any buildings or other structures, natural vegetation, obstructions, etc that may exist on the survey site.

The point cloud is based on very high resolution imagery (20 megapixel, with a ground sampling distance of usually <2 cm per pixel) and each pixel in the image set can be translated into both a georeferenced location and an elevation or height. As with the orthomosaic image, the DEM is a georeferenced output that is projected into a standard plane, usually WGS84 for geographic coordinates and NAD83 for vertical coordinates.

A Digital Surface Model (DEM) shows relative elevation using colour and is the building block for precision contour maps and 3D site models

Because Queensland Drones uses precision ground control points, our DEM coordinates are usually accurate to less than 0.15 cm horizontal and less than 0.25m vertical, so they can be used for construction design integration. Queensland Drones can also classify the DEM to effectively remove all trees, buildings, other structures and obstructions in the point cloud and render a DEM of the bare earth for site redesign.

Virtual 3D Model

The precision point cloud developed through drone surveys to create the DEM is also generated as an LAS file for rendering as a virtual 3D model. This model has many practical applications including being able to view the construction or development site from any angle and any height, create virtual fly-through videos and more.

A virtual 3D model created from the LAS point cloud and DEM can be viewed from any angle or imported into CAD and BIM systems

The LAS point cloud data used to create the 3D virtual model can be transferred to AutoCAD using Autodesk Recap, saved as a Recap project and then directly imported into AutoCAD. It is also possible to use Revit for transferring the LAS file to AutoCAD.]

KML Tile Set

The orthographic image used for the GeoTIFF creation can be exported as geo-referenced XML-based KML tiles which can easily be imported into other packages like Google Earth Pro and overlaid on other data layers to achieve maximum productivity from drone surveys.

A KML or SHP tile set is a very high resolution geo-referenced image set which can be layered with other GIS mapping products

Although this output looks similar to the orthomosaic output, it’s ability to be overlaid on other GIS mapping layers makes it even more useful.

Contour Map

The DEM data developed for the above outputs can be rendered as precision contour maps, much like a topographic map from drone surveys but in a form that can be overlaid onto many other geo-referenced data types. Each line in the contour map represents a set elevation over a section of the site. New lines represent a change in the elevation equal to the contour separation provided.

A precision contour model of a site in progress can identify compliance issues and ensure that earthworks are progressing to the plan

Queensland Drones uses precision ground control points (represented above as green discs) to orthorectify the underlying data behind the stitched imagery, so we can generate contours at intervals of 0.25m, 0.5m or 1m for incorporation into design systems and design drawings. The precision of these contours can be as good as 1-2cm horizontal vertical. These contours can delivered as SHP shape files and/or as KML/KMZ files, or as DWG/DXF/CSV data files.

To find out more about how our Drone Surveys and Aerial Mapping Services can benefit your projects, give us a call on our toll-free number below, or use one of the other links to request a quote or a callback, usually within one working day.