An Introduction to 3D Scanning

3D scanning is the process of analysing real-world objects or environment to collect three dimensional data of its form and colour. The collected data can then be used to construct digital 3D models. It is a non-destructive, non-contact technology. 

3D scanners can either be handheld or use a fixed (usually on a tripod). 

There are many different types of 3D scanners, which each have different applications. See below for more information on the different scanners available at uCreate and their uses. 

There are many different types of 3D scanning, each with their own pros and cons. However, for (almost) all 3D scanning techniques, the underlying process remains the same:

• A point is captured of the object that is being scanned. This is done multiple times over until you have a point cloud. A point cloud is made up of thousands (sometimes millions) of points, each with an x, y and z coordinate, matching a point on the surface of the object that is being scanned. 
• A surface is then wrapped around the point cloud, to create a polygon model. This is called meshing and turns the scan from data on the screen to something that could be 3D printed. 
• If the scanner can capture colour detail, this colour information is projected on to the polygon model as a texture, adding an extra layer of visual detail.

Different types of 3D scanners use different approaches to capture the point cloud. With variations in speed, level of accuracy, point cloud resolution and size of the object which can be scanned.

For more information on how a specific scanner works, see the scanners individual knowledge base page. 

3D scanning is used across a wide range of industries, such as entertainment, medicine, architecture, engineering, history, design, and forensics. Some examples are:

• Producing CAD models for 3D printing. For example, recreating household items for repairs. 
• Scanning buildings and environments for architecture.
• Digitally conserving heritage objects, artifacts, archeological sites or artwork. 
• Reverse engineering (analysing an existing object). 
• Capturing details of complex geometries and irregular contours, which are impractical to measure, model or estimate with traditional methods.
• Scanning people. 
• Creating models for digital display. 
• Artwork.

There are many different types of 3D scanners, which each have different applications. See below for more information on the different scanners available at uCreate and their uses. 

3D scanning is used to create point clouds, which are used to create meshes. A point cloud is a set of points, all with X, Y, Z coordinates, which make up an object. A mesh is 3D representation of an object and in the case of 3D scanning, is made from connecting the points in the point cloud together. 

From 3D scanning, you are able to create both watertight and non-watertight meshes. A watertight mesh is suitable for 3D printing as there will be no holes in the final object. A non-watertight mesh is not suitable for 3D printing. The image below shows the difference between a non-watertight and watertight mesh.

The different file types users can get from 3D scanning are:

Point clouds: There are a variety of different point cloud files, depending on the type of scanning you are doing. These include PTS, BLK, e57, LGSX, ASC etc..... 

Mesh: STL (form data only), OBJ (form and colour data)

When generating an OBJ file, you will also get a JPG, this must stay with the file for the colour data to remain. 

At uCreate, we have a variety of 3D scanner technologies, which are all used for different applications. If after looking at this guide and the 3D scanning knowledge base, you are still unsure which scanner would be best for your application, email ucreate.makerspace@ed.ac.uk or visit the makerspace and speak to a member of staff.

We offer training sessions for our 3D scanners. These are bookable via our events calendar. 

Training for EinScan is optional (but advised). Training for LiDAR is compulsory. 

uCreate has object scanners set up in the Digital Transformation suite, as well as available on our loans service. When booking out a scanner on our loans system, users must also reserve a scanning laptop to go with it. The laptops contains the licensed software which runs the scanners.