point cloud of neighborhood

What Are Point Clouds, And How Are They Used?

You may have heard of a “point cloud” before, but perhaps not really known what the term meant. Watch our video below to understand exactly what a point cloud is, how they are created, and how they are being used in different industries.

 

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Point Clouds Defined

Point clouds are essentially the simplest form of 3D models. They are collections of individual points plotted in 3D space.

Each point contains several measurements, including its coordinates along the X, Y, and Z-axes, and sometimes additional data such as a color value, which is stored in RGB format, and luminance value, which determines how bright the point is.

 

 

diagram of points plotted in 3d space on x, y, z axes

How are they created?

Point clouds are created by performing a scan of an object or structure. Scans are completed by using either a laser scanner or through a process called photogrammetry.

 

icon of laser scanner and stack of photos

Laser Scanners

Laser scanners work by sending out pulses of light to the surface of an object and measuring how long it takes each pulse to reflect back and hit the scanner. These measurements are used to determine the exact position of points on the object, and these points then create a point cloud.

 

laser scanner scanning brick wall

point cloud generated by laser scan of wall

Photogrammetry

Photogrammetry is the process of creating measurements from pictures. It uses photos of an object taken at different locations to triangulate points on the object and plot these points in 3D space. You can use virtually any camera for this process, and again the end result is a point cloud.

 

points plotted on aerial photos of construction site using photogrammetry to triangulate point position

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So, how are point clouds being used?

The primary purpose of a point cloud is to create a 3D model. The point cloud itself can be experienced as a 3D model, but often the point data is first converted into a polygon mesh because most 3D software programs work with polygons.

3D Surface Conversion

Point clouds can either be directly rendered and inspected or converted into models using various shapes and patterns.

CAD Models

CAD, or Computer Aided Design, is the term used to describe the process of using computers to create, analyze, or optimize digital models and has been widely used in construction and design since its rise to prominence in the 1960s. Today’s CAD applications, designed by companies such as Autodesk, Dassault Systems, Siemens PLM Software, and PTC, offer advanced rendering and animation capabilities enabling engineers to better visualize their product designs. 4D BIM, also known as construction sequencing, is a type of virtual construction engineering simulation that helps engineers visualize the project by combining 3D models with the project schedule.

Polygon Mesh

Polygon Meshes are comprised of simple polygons and elements such as vertices, edges, faces, polygons and are used to digitally reconstruct the surfaces (not volume) of objects. 

Triangle Mesh

A triangle mesh is a type of polygon mesh comprised of triangles connected by common edges or corners.  Components of triangle meshes include vertices, edges, and triangles.

NURBS Surface Models

The Acronym, NURBS, stands for Non-Uniform Rational Basis Spline and is a mathematical model used for producing and displaying curves and surfaces. The mathematical complexity of NURBS is often simplified by user-friendly tools found in 3D modeling & animation programs such as Autodesk.

 

polygon mesh of construction site

3D Models

The accurate 3D models formed by point clouds are used in a variety of ways across different industries. In the architecture industry, 3D models created by laser scans help produce as-built drawings and models, which capture the current condition and layout of buildings. The accuracy of the 3D models means they can be used for measuring distance, area, and volume which is beneficial for construction and restoration projects.

 

area measurement being made on 3d model

Point clouds and 3D models are also popular in manufacturing. Parts and components can be scanned and turned into 3D models, which can then be brought into CAD programs for refining and manipulating the design of the object.

People choose to use point clouds because of the Point Cloud Library, which is an open-source project. The point cloud library is an open-source framework that includes algorithms and tools for manipulating and refining your point cloud data. 

point cloud of neighborhood

Poing clouds are relatively universal forms of capturing and storing 3D models and have a variety of use cases across different industries. 

 




About the Author

Stetson Doggett

Stetson is an Ithaca College alum and a certified drone pilot. He has been flying the DJI Mavic Pro since it first came out and loves finding new ways to improve his aerial photo and video quality. Stetson is from Acton, Massachusetts, and when not in the air he enjoys playing board games, producing YouTube videos, and watching Stranger Things.