city view with snow topped mountains in background
Written by David Dengler

Drones for Architecture

Episode 1: Veritas

As an architect, you may wonder if can you leverage drone technology in your current workflow? The answer is – Yes! Let’s look at how and where it makes sense. Drones can provide meaningful data throughout the entire process – from concept through completion.

Many firms are discovering that out-sourcing or subcontracting drone technology, saves them time and money on all kinds of projects. The technology is safe, scalable, and easy to integrate into your current workflow and share with the project stakeholders.

Here are some ideas for integration:

  • Pre-Construction and Planning
  • Earthwork
  • Foundation and Utilities
  • Vertical Construction
  • Project Closeout\
  • Facilities Management
  • Project Marketing Materials

A Single Source of Truth

For now though, let’s focus on a high-level concept drones can provide that speaks to the above list. A Single Source of Truth. What do we mean by a single source of truth?

drone-aerial-ground-shot-1 drone-aerial-ground-shot-2 drone-aerial-ground-shot-3

Achieving a single source of truth means being able to operate at an enterprise-level, system-wide, cross-platform, and cross-discipline by sharing the data most recently collected from the field as a foundational source. Or put more simply, all the stakeholders on the project know the exact current state of the project. The benefits are realized in saving time, scheduling, ordering, waste control, conflict resolution, expediting RFIs, safety, and more. The drone imagery also creates a historical record that can be used for verifications, if required.

Does this sound like a monumental task? It really isn’t. And the best part is having a single source of truth that is scalable along with the scope of a project. Drone technology can be implemented at a base subcontractor level for the entire project, or simply on demand when needed. Some firms require daily flights while others only need one or two flights for the entire project. The level of integration is dictated by the project itself.

The collected imagery and data processed create one undeniable source of truth where all stakeholders are assured of the current state of the project. Are the teams on schedule? Do RFIs get back to the field in time to avoid timeline delays? Is everyone communicating? You can have these answers, many times, before they become questions.

So how can you achieve the project “truth”? We use a process called photogrammetry.

The Photogrammetry Process

Wikipedia defines photogrammetry as “the science of making measurements from photographs, especially for recovering the exact position of surface points. Photogrammetry is as old as modern photography, dating to the mid-19th century and in the simplest example, the distance between two points that lie on a plane parallel to the photographic image plane, can be determined by measuring their distance on the image, if the scale of the image is known.”

Drones are the perfect tool to accomplish photogrammetry, using GPS, and known points on the ground called Ground Control Points (GCP). The drone flies in a precise pattern and altitude while taking hundreds, and sometimes more than a thousand photographs.

drone image showing control points

Next, the imagery is coordinated using the photographic metadata and the GPCs in post flight processing to create a point cloud. While it is possible to work directly from the point cloud (delivered in .rcs or .las formats), you can also produce several other formats that many client find more usable.

The additional formats include:

  • 2D Orthomosaic (.tiff) a flatten 2D image that is created from the photographs and is stitched together by referencing the point cloud making it scalable and able to be used as a background image. These are very high resolution aerial images.
  • Digital Terrain Model, DTM (.tiff)
  • Digital Elevation Model, DEM (.tiff)
  • Contour Model (.shp, .dxf) These are survey grade accurate.
  • 3D Mesh (.rcm, .obj) Similar to what you see in Google Earth but much higher resolution.
  • Even native AutoCAD and Revit files where you can start your design work.

Again, the project is what drives the technology and the information that you need. And using an outside contractor relieves you from the burden of technology investment, education, certification, and most notably the liability.

Once the site has been ‘scanned’, you have a digital twin of reality – in this case, the truth of the project at a point in time. And, by sharing the digital twin with your project team and stakeholders, everyone is working with the same reality. Consider the effect on weekly team meetings where the exact site image can achieve faster solutions and reduce disputes.

How do you get started? Contact a reality capture service provider such as Kelar Pacific. Compare your typical process for existing conditions to one using drone technology. You will find you can receive the data faster and eliminate return site visits as the design process begins. The progress reports provided by drone imagery are especially useful for tracking project milestones and more.

A single source of truth – the drone way.

%d bloggers like this: