I’ve been working in reverse engineering and 3d scanning for ~ 20 years now. The objective has always been to create a useful CAD model from an existing part.
In the early days, the process was cumbersome, but straightforward. We would manually measure key features of the part, then enter those dimensions as we created our 2D AutoCAD drawings. For non-critical features, we would use our engineering judgement to come up with something that looked close enough.
The advent of portable CMM’s like FARO and Romer Arms created significantly more capability, especially for capturing complex dimensions or profiles.. Direct interfaces into programs like AutoCAD greatly reduced the number of manual dimensions that had to be entered. However, since the data was sparse, there was still a great deal of liberty when it came to creating the final CAD model.
3D laser scanners added a whole new dimension to this process. Now we could capture millions of data points to fully define the entire surface of the part. By the early part of 2000, this data could also be rendered or shaded in real time on the computer screen, making it look like you had a real CAD model.
This was great for visualization, but could also be very misleading. Although experienced CAD operators would know that this shaded point cloud or polygon mesh was essentially useless in a CAD system.. .upper level managment would not. This would often lead to conflicts regarding schedules and expections…. “why isn’t that done yet?”… “I saw the whole thing on the screen”.
A quick fix to that problem came in the way of rapid surfacing or Auto-Surfacing made popular by Geomagic. A Geomagic surface model could be easily imported into CAD, created an accurate representation of the part, and could be manipulated to some degree.
The next evolution in scan data processing came in 2006, with the release of Rapidform XOR. XOR actually follows the paradigm of common CAD systems, by allowing the user to develop 2D sketches based upon the scan data, and extrude, sweep or revlove them into solid bodies. This parametric CAD modeling process finally produces the type of results that we had all been waiting for.
The release of Rapidform XOR3 now takes this process to a new level, by introducing solid modeling wizards. The scanned data is segmented into regions, then wizards can be used to automatically extract solid bodies, with their associated sketches, bringing us one step closer to the “make a solid model” button.