SLAM Technology Speeds Up Mapping of Art Deco Skyscraper

A Brazil-based architecture firm benefited from using innovations in GeoSLAM’s handheld scanners, enabling site teams to complete a survey four times faster than by using traditional methods.

To produce as-built architectural 3D drawings of a 32-floor, 130m art deco skyscraper located in Belo Horizonte, PARAGRAM Architecture and Consulting enlisted the help of GeoSLAM’s ZEB-REVO, a lightweight mobile mapping device powered by SLAM (Simultaneous Localisation and Mapping) technology that anyone can operate by simply walking around holding it.

Almost every complex building or renovation project in Brazil is governed by strict time constraints, and a major upgrade to the Acaiaca Building, which dates back to the 1940s, was no exception. The multi-purpose structure, once home to a nightclub, cinema, shops and an air-raid shelter, is today used as an office space and as a place of worship.

In order to progress with the retrofit of the electrical installations and fire prevention plan, Belo Horizonte-based PARAGRAM was commissioned to produce 3D drawings of the structure, ensuring both health and safety measures were met, as well as maintaining the preservation of the architecturally significant building.

Working alongside contractors Criar Projetos e Consultoria and putting to use GeoSLAM’s innovation, the process began to take shape.

Early Beginnings

Despite the scale of the project, PARAGRAM initially planned to conduct a manual survey of the building, measuring a total of 8,357m sq. Using only laser tape and paper to document the as-built structure, estimates suggested this traditional method would have taken three employees over 40 hours to complete.

In order to preserve time and money, the team turned to GeoSLAM’s ZEB-REVO. Its ability to generate scans within a few centimetres of accuracy at a rapid pace without the need for GPS, made the technology an attractive prospect for the project management team.

The Next Level

The hallway of the stairs and elevator were used as the starting point of each scan to help align the point clouds, the project got underway. The scanner was programmed to achieve the maximum consecutive levels in just under 20 minutes, with minimal overlap between each shot.

Taking just ten hours to complete a full scan of the building’s interior, with one operative scanning and another taking a photographic record, the as-built architectural 3D drawings were complete in a quarter of the time that traditional methods would allow.

Results

As well as delivering on speed, the team was also impressed by the accuracy and portability of the ZEB-REVO. Jose Vargas, BIM technology consultant at PARAGRAM Architecture and Consulting, said “We were able to gather much more information than first anticipated, such as the registration of beams, roof trusses and other structures, as well as a detailed survey of exposed electrical installations and engine rooms in areas that would have been very difficult, not to mention time-consuming, to access. What really stood out was the quality of information captured, which was easily incorporated into a BIM representation, using Revit software. The device was really easy-to-handle and it was remarkable how much detail we were able to capture in the point clouds. It enabled us to achieve a level of accuracy that would have been impossible using manual surveying techniques.”

Planning for the Future

A much-loved part of the Belo Horizonte cityscape and a distinctive mark of the city’s past, the Acaiaca Building has made its way into the history books, recognized for its unique style and carved figures on its exterior.

This particular project is testament to the rapid modernization of heritage buildings, and an example of how an asset can evolve to meet the demands of current and future users, especially when owners are prepared to make the necessary investments to preserve a piece of history.

This article was published in Geomatics World May/June 2019