Drone orthomosaic maps have changed the game for construction companies. These highly detailed maps give construction companies a completely accurate and comprehensive view of their project sites at any time. This gives project managers a new level of confidence in their ability to manage their projects ahead of schedule and under budget while keeping investors, stakeholders, and executives in the loop through all stages of the project.
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What is an Orthomosaic Map?
In simple terms, an orthomosaic map is a map made from images puzzled together and geometrically corrected for distortions so that the finished map perfectly reflects the geographic area it depicts.
For our techy folks reading, here is a more technical definition from Esri (the Environmental Systems Research Institute):
“An orthomosaic is a photogrammetrically orthorectified image product mosaicked from an image collection, where the geometric distortion has been corrected and the imagery has been color balanced to produce a seamless mosaic dataset.”
-Esri
An orthomosaic map differs from aerial photography and other photographic maps because it is corrected to remove distortion. In an uncorrected aerial photo, the size and distance between objects can be warped by lens distortion, camera tilt, and topographic relief (elevation changes).
These make structures look bigger, smaller, closer, or farther away than they actually are. Contrastingly, an orthomosaic map can be trusted as an accurate representation of the Earth’s surface. Because the map has been “orthorectified,” it functions as an accurate tool for measuring distances and scale across the Earth’s surface.
How Drone Images are Turned into Orthomosaic Maps
Drones are powerful tools for creating orthomosaic maps of construction sites because they can cover a lot of ground quickly while maintaining accuracy. Using drone software, the drone pilot can program his craft to fly the site autonomously, taking hundreds or thousands of photos.
The pre-programmed flight path makes a huge difference in the quality of the finished map. When creating an orthomosaic map, the drone pilot has to consider three important factors: resolution, overlap, and relevancy.
Drone Pilot Considerations While Gathering Images
- Resolution – high-resolution images are easier to work with during post-processing and impact the quality of the finished map
- Overlap – there must be enough images captured to ensure there are no gaps in the data. On average, orthomosaic maps require an overlap of 70%.
- Relevancy – irrelevant views should be avoided, such as images taken during takeoff, landing, or sharp turns. These unnecessary images introduce ambiguity and distortion into the map.
Today’s drones are equipped with incredible maneuverability. With features such as waypoint paths, 360° gimbal rotation, obstacle avoidance, hovering, and optical zoom, they make it easy to collect data for orthomosaic maps.
The drone images are also encoded with metadata that is incorporated into the map—relaying important information about the location and conditions during which the images were taken, such as time of day and weather.
Other methods of capturing aerial photography, such as manned aircraft and cranes, don’t provide the same level of flexibility or quality. They are more expensive and present more safety risks. A qualified drone professional can capture the data you need at a fraction of the cost while improving the quality of results and safety of the project.
Orthomosaic Map Example of Construction Site
How Orthomosaic Maps are Used in Construction
In construction, orthomosaic maps are used to measure, analyze, and report progress on a project site. These geometrically correct maps are utilized for:
Uses for Orthomosaic Maps in Construction
- Pre-construction planning
- Site surveys
- Progress monitoring
- Visual record keeping
- Stockpile measurements
- Cut and fill calculations
- Material and labor cost estimates
- Infrastructure inspection
The list can go on, and there are ways to customize an orthomosaic map’s functionality to meet the exact needs of your specific construction project. 2-D Orthomosaic maps can be built upon to create more layered and complex maps, such as annotated maps, 3-D site models, and 4D BIM plans. All of these maps start off as aerial photos captured by a drone and then processed and pieced together using drone mapping software.
Drone Orthomosaic Maps are Current, Trustworthy, and Detailed
Many construction companies rely on outdated satellite imagery of their project site— pulling images off the internet from sources like Google Maps. The issue with this is that these images are not updated frequently enough to provide current information about the site. Instead of relying on low-resolution and out-of-date satellite images, construction companies are better off investing in their own drone maps. Construction companies can hire a drone services provider to make frequent drone flights over the site and produce orthomosaic maps that are current, trustworthy, and detailed.
Aerial Orthomosaic Maps Streamline Planning
From pre-construction to the final inspection, drone mapping can streamline every stage of a construction project. During the design process, drone maps can help engineering teams tailor their designs to the site and account for any unique topography like elevation, drainage spots, vegetation, and waterways. This will cut down on design changes once construction has started, saving time and money.
Another use for orthomosaic maps during the planning stage is to overlay building plans on top of the orthomosaic map to catch conflicts early on before they become costly. This article from DroneDeploy tells the story of a project manager on a 67-home residential building project who discovered a conflict between utility services and one of the houses. The PM told DroneDeploy it would normally “take me months to find out” about issues like this, but drone mapping made it possible for him to discover the conflict fast enough to put a solution in place.
What's included in YOUR GUIDE...
A Proven Roadmap of Success for Implementing Drones in Construction.
A List of Red Flags to Avoid When Hiring Drone Service Providers.
How to Persuade Your Leadership Team to Leverage Drones on Every Jobsite.
As the project progresses, drone maps continue to be a useful tool. These aerial construction maps offer a cost-efficient alternative to manual surveying, provide high-quality data for virtual collaboration, and make it easy to communicate virtually with off-site stakeholders.
Construction Orthomosaic Maps Improve Communication
Orthomosaic maps are excellent communication tools for both on-site and off-site project members. Off-site executives and stakeholders can stay updated on the project’s progress without making so many trips to the physical site location. Instead, they can view digitally shared, orthomosaic drone maps of the site.
The extraordinary amount of detail contained in an orthomosaic map, plus the added capabilities of annotation and built-in measuring tools, can answer any questions off-site project members have.
ACT Engineers, a client of The Drone Life, experienced the communicative benefits of drone imagery when they used drone footage to help secure $2.3 million in funding for a restoration project in New Jersey.
"The use of visual drone images was greatly beneficial for pre-planning and communicating the scope of the project."
-ACT Engineers
On-site project members benefit from improved communication through the use of orthomosaic maps, too. Orthomosaic maps made with drone imagery are faster to obtain than traditional survey methods using aircraft or cranes to get an aerial perspective.
The speed of data collection and clarity of information facilitates prompt decision-making and increases productivity on site. Shared access to orthomosaic maps makes it easier for project managers to verify completed work, plan schedules, and regularly document the project.
Drone Orthophotographic Maps Save Money on Construction Sites
The efficiencies of drone mapping bring about huge savings for construction companies. We’ve already discussed the qualitative improvements that reliable aerial imagery (as drone orthomosaic maps) brings about—more current information, higher quality images, streamlined planning, and improved communication. These go hand-in-hand with quantitative improvements for construction companies too—i.e. time and money saved.
With the improved quality of information and increased frequency of information updates, project managers can move their construction projects along faster. Orthomosaic maps clearly communicate the progress to project managers, clients, and investors to keep all relevant parties updated. With this information in place, workers free up time for other tasks.
The reliability of drone orthomosaic maps makes them a good tool for cost estimating when it’s time to order materials. Drone mapping software offers built-in measurement tools for stockpile measurements and accurate measuring of site dimensions or distances between points on a site. Orthomosaic maps are extremely accurate and reduce the likelihood of human error when measuring for cost estimates, saving the company money by avoiding oversupplied materials.
Game-Changing Results from Orthomosaic Maps
Construction companies can obtain game-changing results when they use orthomosaic maps as part of their workflows. We’ve discussed throughout this article how drone orthomosaic maps bring about higher quality data, more efficient project planning and project management, better communication, and time/cost savings.
If your company is ready to use aerial drone imagery like orthomosaic maps on the construction site, learn more about our drone services for construction companies here.
The speed of data collection and clarity of information facilitates prompt decision-making and increases productivity on site. Shared access to orthomosaic maps makes it easier for project managers to verify completed work, plan schedules, and regularly document the project.
Next Steps: Getting Started with Drones in Construction
Implementing drones in your construction workflow can completely change your companies’ operations throughout the entire bidding, planning, and building process. The Drone Life specializes in partnering with construction and engineering companies to minimize pain points, increase profit margins, and ensure that projects are completed within deadline. Learn more about our solutions, completed projects, and pricing here.
For even more information about using drones in the construction industry download our completely free and value-packed PDF – Drones in Construction: The Ultimate Guide.
What's included in YOUR GUIDE...
A Proven Roadmap of Success for Implementing Drones in Construction.
A List of Red Flags to Avoid When Hiring Drone Service Providers.
How to Persuade Your Leadership Team to Leverage Drones on Every Jobsite.
