The introduction of laser scanning and point cloud technology has revolutionized the Architecture, Engineering and Construction (AEC) industry. These technologies have significantly improved the process of recording and analyzing existing building data, making it easier and faster to obtain detailed 3D information and make precise measurements. Laser scanning and photogrammetry are popular point cloud reconstruction techniques that enable the capture of the geometry and appearance of a targeted structure. Laser scanning is a particularly powerful technique that can provide millimeter-level accuracy and high speed scanning of large structures in the AEC industry.

Laser scanning as-built BIM is an increasingly common approach used in the AEC industry to produce clear 3D information in the form of high-density point clouds. Point cloud data from laser scanners is the simplest form of 3D information, representing coordinates and the texture of a real-world scene. This real data can then be used to create a 3D geometric model of the structure, allowing for more accurate design and analysis for renovation purposes. In addition, recent research efforts have focused on developing strategies to automate the process of reconstructing building information models (BIM) from laser-scanned point clouds. This technology has the potential to revolutionize the AEC industry by reducing time and costs, improving workflow efficiency, and increasing accuracy.

Data collection:

The next step in creating 3D as-built documentation is to collect accurate data of the existing structure. This may involve using various equipments such as terrestrial laser scanners, SLAM based mobile laser scanners, and photogrammetry to capture the whole site with precise dimensions and color information.

Data processing:

Once the data has been collected, it needs to be processed and converted into a digital format that can be used to create the desired product. This involves registration, coloring, filtering and exporting the data for further use. Even though most of the laser scanner manufacturers have cloud to cloud or similar automatic registration algorithms in their equipment or software, for precise projects we do use target registrations that are connected with control networks to deliver the best quality point cloud data. Target based registrations allow us to use bundle adjustment methods so that we can have thousands of scans registered together with rms of under 5 mm.

Coloring is an automatic process for scanners with integrated cameras. But if we need to capture more detailed color information using professional cameras, than we do the coloring of the point clouds using photogrammetrical techniques.

Filtering is a really important step especially for phase based laser scanning systems. The unwanted data that is caused by fog, rain, steam, material of the objects, or reflections from windows/mirrors should be filtered out before exporting the point cloud data to further process.

End Product:

The next step is to create a useful end product for architectural use. This can be a 3D BIM model, 2D drawings, layouts and orthophotos. Even though there are software that aid us to generate semi automated BIM models, we still have to do the conversion from point cloud to BIM model by experienced team members. For the architectural firms that are working in 2D, laser scanners still offer a lot of possibilities. We use 3D point clouds to create accurate layouts, sections, plans, and facade drawings.

For historical preservations projects, the end product can be a 3D textured mesh model. In that case we may use laser scan and photogrammetry together to create highly detailed digital twins of the heritage buildings or monuments.

Quality Control and Validation:

Once the 3D model has been created, it needs to be validated to ensure that it accurately reflects the structure as it was built. This may involve comparing the model with the original data and making adjustments where necessary.

Documentation:

The final step is to create detailed documentation of the end product, including drawings, plans and specifications that can be used for various purposes such as renovation, maintenance or compliance with building regulations.

In general, the process of creating 3D as-built documentation requires a combination of technical expertise, specialized equipment and software tools to capture the right data and create an accurate digital representation of the existing structure.

Overall, having 3D data can provide architects with a powerful tool to improve the design process, increase accuracy and enhance collaboration and communication with stakeholders. The architects we work with frequently request façade drawings, floorplan, sections and elevations. Solvotek International has all the experience and technical background to meet the needs of your project.