Article by Jean Thilmany
If you’re taking a 3D laser scan of your site’s as-is condition and turning that information into a 3D CAD model to estimate, detail or make renovations to MEP projects, you might wonder just what a point cloud is. To understand a point cloud, it’s important to learn how it’s created in the first place.
It actually takes three steps to get a site from a scan to model
- Scan the warea with a 3D laser scanner
- Import the point cloud into modeling software to visualize the area
- Export the point cloud and import it into a CAD/BIM system
So…what is a point cloud?
When you take a scan, the laser scanner records a huge number of data points returned from surfaces that you’re scanning. These can include walls, windows, ductwork, steel structures, etc.
A cloud is a 3D mass made up of small droplets, crystals, water or various chemicals. In the same way, a point cloud is a huge number of tiny data points that exist in three dimensions. If you could split those points out of a scanner, they’d appear as a cloud you could walk within.
So the point cloud that the laser scanner captures is an accurate as-built of an object or space. It’s saved in the form of a very large number of points that covers surfaces of an object or structure.
By setting up and taking scans from multiple locations, you can get a complete view of a target area. The multiple scans can be taken into a scan registration software, such as Trimble RealWorks, to “stitch” everything together.
Once imported into scanning software, the points cloud data can be parsed, manipulated and modified, providing for data management, analysis and advanced 3D modeling.