Regular and accurate site surveys are crucial to control the quality and monitor the progress of the construction site. Although drones are suitable for collecting such site data, they have various limitations. Alternative solutions are therefore required to complement drone-based surveying systems.

A camera mounted on the tower crane is an excellent alternative to drone mapping. Tower cranes are already present at construction sites, and no flight permission is required. In places such as urban districts and airport zones, where drone flights are sometimes difficult or even impossible, a crane camera is ideal as a long-term alternative, or it can work alongside and complement drone imagery.

Revolutionize the Way to Verify the Progress of Construction Site

Anavision has recently deployed a tower crane camera solution for construction sites in Hong Kong that uses a high-resolution camera mounted on the jib of a tower crane to take pictures for the entire duration of the project, and through artificial intelligence image analysis and 3D reconstruction, to produce a high-resolution floor plan.

An Intelligent Tower Crane Camera Solution tower crane camera solution — Figure 1: By using the photos captured from two tower crane cameras can generate a high-resolution stitched image (DOM) of the entire construction site.

By overlaying the CAD drawings for comparison, the tower crane camera solution is able to detect construction errors, such as external wall errors before building the next new floor, and allow on-site corrections in advance to avoid high rework costs in the future, thereby greatly improving the working efficiency of site surveyors and reducing the manpower.

CAD comparison — Figure 2: CAD drawings are overlaid on the DOM, and the errors above the tolerance will be marked in the report.

In addition, with the high-altitude characteristics of the tower crane, the solution has the advantages of long-time aerial standby and high load, to realize high-density measurement of a large area within the construction site. It also greatly reduces the number of workers to work in the danger area, and improves the safety of the working environment on the site. After the inspection is completed, the site manager can receive the report via email, which helps the site plan follow-up actions and decision-making.