Mapping: Orthomosaics, 3D Meshes, and Elevation/Topographic Maps
Whether it’s mapping a field to analyse plant health, using a Digital Elevation Model to plan cut/fill operations, measuring and monitoring stockpile volume, or verifying as-built matches as-planned, drone mapping and photogrammetry can dramatically improve the quality of your decisions via superior data. There are five key deliverables that you can obtain from a drone mapping mission: orthomosaic maps, point clouds/textured meshes, elevation maps, and plant health maps. Each of these maps are created by digitally stitching together hundreds of 4K images with common features and reference points using advanced software such as Pix4D and DroneDeploy.
When considering hiring a drone pilot to do a mapping mission, it’s important to consider the parameters of your project. Different types of projects and different accuracy requirements require different approaches. Let’s examine some of the most common applications and the requirements of mapping each.
Photography & Video
Easy Scheduling
Quick Turnaround
Customized Solutions
Orthomosaic Maps from Aerial Drones
Orthomosaics are maps that have been orthorectified by advanced image processing software such as DroneDeploy and Pix4D. They are invaluable to anyone who needs to make accurate measurements of distance, angle, volume, or elevation at a construction site, farm field, zoning request, or property analysis. When looking at a properly georeferenced orthomosaic map, you can be sure that everything you’re seeing matches the physical world precisely enough to plan cut/fill operations, measure stockpile volume, or do site planning. Depending on the acquisition process and specific site hazards, most orthomosaic maps Aerial Hawks delivers have errors as low as 1in horizontally and 1.5in vertically. Land surveying crews can produce maps with a similar level of accuracy, but at half the speed and four times the cost. Although Aerial Hawks are not licensed land surveyors, we have them legally validate our results so we can deliver extremely accurate orthomosaics that are suitable for construction, agriculture, insurance and legal purposes in days, not weeks.
3D Textured Mesh
Compatible with applications such as ArcGIS, AutoCAD, and others used in agriculture, construction, and utilities industries, 3D meshes are capable of providing insights into your project that no other deliverable can. They allow quality assurance and safety inspections to be done remotely and comprehensively. As-built, cut/fill, and site planning are made easier with an accurate model of the ground and existing structures. Try out our sample 3D model of a spillway construction site below:
(Embed sample DroneDeploy 3D model with annotations)
3D modeling of existing sites is unique to the drone industry and is something land surveyors cannot provide. We use a similar process to make these models as orthomosaic maps: taking hundreds of 4K images at low altitudes that form a grid over the project and then digitally stitching them together. Careful flight planning can accurately capture complex structures with details such as overhangs, valleys, spirals, debris, and other features that are difficult to examine on a 2D map.
Elevation and Topographical Maps
Digital Terrain and Elevation models are crucial for site planning and analysis. Terrain models subtract buildings and other artificial features from the elevation map while Elevation models include them. Aerial Hawks can deliver models compatible with the leading design software, such as ArcGIS and AutoCAD, in formats such as Cut/Fill DSM/DTM, Contour DXF and Contour SHP, and GeoTIFF, among others.
Here’s an example of a topographic map (DEM) Aerial Hawks made of a spillway construction site. There is around a 50ft difference between the south side of the spillway (the bottom) and the lake above it, but other projects will have a greater difference between the lowest and highest areas of interest. Typically projects that have a greater than 60ft difference are more easily analysed using specialized software, instead of web applications such as DroneDeploy. In this instance DroneDeploy provided the information our client needed without having to export DSM models.
We used optical sensors, not LiDAR, to create it, although some projects warrant using LiDAR due to its ability to penetrate through brush and grass to the ground. Many agricultural applications and wide-area flights use a combination of LiDAR and fixed-wing drones, which are able to remain in the air far longer than rotary drones, at the expense of maneuverability.
Construction 3d Modelling
Accurate to the centimeter (0.4in), drone scanning and 3D imaging allows project managers and owners to integrate real-time models into their project management workflow. Implementing real world data and 3D models into software such as AutoCAD allows the virtual design process to plan out a project more efficiently or monitor one in-progress. These results can also be used to measure volumes of stockpiles, check distances, plain cut/fill and grading operations among many other applications. Aerial Hawks’ drones make all of these tasks painless and inexpensive compared to land surveying and ground crews.
