Project

When working on a project in Switzerland, international construction company Marti used a new construction verification solution from Pix4D. Marti operates in all major areas of construction, including structural and civil engineering, tunneling, and road construction.

 

While building in Lausanne, they combined daily drone flights for data capture with Pix4D software for creation and visualization of mapping results on a web-based software platform.

 

3D model of Lausanne site, produced by processing drone-acquired images with Pix4D software.

Data Acquisition and Processing

Although image data capture from drones is not new, the automated process which simplifies image acquisition, processing, and distribution of data is. The workflow is automatic and therefore repeatable on a daily basis, something that would be difficult and expensive to achieve if multiple manual processing steps had to be followed.

 

  • Pix4Dcapture defines flight path and serves as autopilot for flight and image capture.
  • Images are transmitted and processed in the cloud.
  • Orthophotos are uploaded to Pix4D web platform.

Analysis and Decision Making

After the orthoimage has been produced and uploaded to the Pix4D web platform, it is viewable by anyone with an account and internet access, along with the 3D site model. Make distance and area measurements along with image annotations for comment sharing.

 

 

Orthophoto of Lausanne site: an orthophoto is a mosaic of photos corrected for perspective, fully scaled and measurable. These image maps give a realistic aerial view of the site and can be used for simple visual checks or more detailed analysis. 

Orthophotos are displayed on a timeline and can be compared side-by-side for comparison over time.

Construction drawings, CAD or BIM design models can also be compared to orthophotos, enabling the site manager to check the as-built site status against the design.

Two orthophotos taken on consecutive days, showing meshing progress before a concrete pour.

This allows any mistakes or deviations from the design to be identified and acted on. Construction industry estimates say approximately 15% of project cost is due to rework. By finding errors as soon as possible, the time and money typically spent on rework can be saved.

Comparison of as-built orthophoto and CAD drawing, to check construction status and verify schedule.

Conclusion

Most large budget projects optimize construction by using the BIM process: a detailed construction schedule that must be closely adhered to if the project is to be completed both on time and on budget.

 

Any deviations from schedule must be identified as soon as possible for the BIM process to be corrected. By comparing scheduling drawings to as-built orthophotos, the BIM manager is able to have daily updates on site status, generated by an automatic workflow.