3D laser scanning is a quick and precise method that is typically used by surveyors to capture a building’s spatial detail through the use of laser beams. This non-destructive method creates accurate models from “point clouds” which are the result of fired laser beams hitting physical objects and providing essential information about their exact size and relative location.
A major benefit of this method is that as many as 97,000 points can be measured per second using a 3D scanner and it requires zero contact. This information is then stored digitally to create 3D CAD models used to allocate and adjust materials required in your project and see it come to life.
How Does 3D Laser Scanning Work?
As you’ve already learnt, the 3D laser scanning process relies on a laser beam hitting a desired object but it’s not as simple as that, there are several calculations being made all at the same time. Laser beams that are fired return to the sensor as reflections of different wavelengths offering crucial information about surfaces and structures via a single cloud point. This information concerns how long it takes for the light wave to complete its journey also known as the time of flight.
Millions of these cloud points are then collected to form highly detailed 3D XYZ coordinate data and saved as a point cloud data file. This is made possible through LIDAR (Light, Imaging, Detection and Ranging) technology which captures an array of data far faster than traditional means. This process requires Global Positioning Systems (GPS), Inertial Measurement Units (IMU), receiver electronics, and photodetectors. When complete, the point clouds that they make up demonstrate dimensions and spatial relationships of the structures measured.
Benefits of 3D Laser Scanning
There are numerous benefits of 3D laser scanning, including:
- Obtain data quickly.
- Equipment can be mounted on moving land or aerial vehicles for vast landscape surveying.
- Survey inaccessible environments or those with health and safety risks such as compromised historic buildings.
- Analyse hard to measure topographic features and create project simulations.
- 100% accurate and prevent mistakes that can have disastrous consequences to a project.
- Survey with minimal disruption – this is particularly useful in traffic construction where traffic flow can’t be stopped.
- Being able to virtually “walk through” a site saves the cost of returning to a site.
- Compatibility with many forms of industry leading software such as AutoCAD and Sketch Up.
As well as providing helpful pre-construction surveys to confirm site conditions, these laser scanners can also be used to check progress against proposed designs during construction for quality control purposes and post-contronstruction to evaluate if a project has been completed to specification. Additionally smaller objects and curved items can also be scanned using a digitiser – the possibilities are endless!