3D Scanning

A 3D scanner takes non-destructive measurements of a target object to digitally reconstruct its shape and in some cases texture. A 3D scanner outputs a point cloud, or a series of points in 3D space, that correspond to the surface of the target object. Further post processing can turn this point cloud into a mesh, or a digital surface composed of triangles. Computer assisted design (CAD) software can import this mesh for use in further design and slicing software can turn this mesh into gcode for 3D printing.

3D scanning enhances both reverse engineering and first principle design. 3D scanning enables the rapid translation of physical objects into digital models, accelerating the process of reverse engineering. As meshes produced from 3D scans carry the dimensions of the target objects, 3D scanning reduces the time required to completely measure parts to reverse engineer. As the software used to post process 3D scans can export directly to CAD software, 3D scanning enables the inclusion of existing physical models into a new design, enhancing a project based on reverse engineering.

In addition, 3D scanning enhances original design. Organic shapes, like a human body, pose significant challenges to recreate in CAD. By directly and rapidly digitizing these shapes, 3D scanning enables the design of parts intended to accommodate unusual or organic shapes otherwise difficult to model. Other unique applications of 3D scanning include digitizing artifacts or fossils and capturing an entire room interior for redevelopment planning.

The 3D scanners offered by Terrapin Works capture and orient points on a surface through a range of technologies summarized in the list below:

• Structured light: the scanner emits a pattern of light and a detector registers deformation in its reflection from the target object. The time from emission to detection reveals the distance from the scanner to the object and the nature of the deformation identifies the curvature of the surface. This 3D scanning technology typically offers faster speeds with slightly lower accuracy as compared to laser line scanners.
• Laser line or point: The scanner emits either a point from a laser or rasters a laser line across the object while a detector registers the reflection. The time between the laser emission and detection identifies the distance from the point measured to the scanner. Laser line scanners typically require more time but yield more accurate results than structured light.
• Cameras: Some scanners use cameras coupled with another scanning technology to capture the color of an object and enhance texture tracking. Cameras can also digitize objects through photogrammetry, a process where software reconstructs a 3D mesh from 2D pictures of an object.

The four primary scanners operated by Terrapin Works all have disparate use cases, and successfully completing a scan requires choosing the scanner most appropriate for the object. Use the guide below to select a scanner appropriate for a new job:

All 3D scanning at Terrapin Works costs $25 per hour, including both the scanning time and post processing time. Typically, objects without features notably difficult to scan or that only require limited post processing require between 2 to 4 hours. If an object requires more extensive post processing the time requirement may increase significantly. Before authorizing work on any scanning job, have an experienced Terrapin Works staff member evaluate the target object and provide an estimate.