Scan to CAD, Reverse Engineering, laser scanning, Metrology

Dec 12 , 2016


When working with outside sources to convert physical parts into CAD, it is important to understand what can be acheived. If you do not express what you are trying to capture, chances are you will be dissapointed with the results.  This is just one facet that needs defined, many factors need to be hammered out with the vendor to get you what you want the first time.  Check back often for more....
  1. Design Intent:
    1. Design intent means creating a 3D CAD model which attempts to remove manufacturing features and tolerances. This is used when one wants to retain intentions such as concentricity, parallelism, common fillet sizes, perpendicularity, hole patterns, arrays, etc.  Assumptions are made by the designer based on what he sees as obvious.
    2. Some subjectivity is present here, so any background information or matting component geometry is recommended.
    3. Shrink is not taken into account, unless provided.
  2. “As Is”:
    1. “As is” refers to modeled as the part is scanned. The modeler surfaces what is actually in front of him. Hole spreads are not perfect, Cylinders not concentric, Perpendicularity is not considered, etc.  The CAD designer merely fits surfaces to the scan geometry
    2. This is commonly cheaper, however when arrays and circular patterns are present, this become much more expensive.
    3. If your intention is 2D prints, this may not be the way to go, as it is difficult to create views and document surfaces that are not normal to the views you will be creating.
  3. Hybrid:
    1. If one prefers an “As is” model, however would prefer certain aspects to be patterned, this can still be accomplished with some forethought and communication. For example, if one is scanning a Turbine and wants circular pattern used on an “Average” blade, we can do this.
    2. This can be a good option for parts with large amounts of patterned geometry.

I am always looking for interesting things to post about, so check back often, leave a comment or suggest a subject.

Thanks for your interest!

Nathan Garrett

About Nathan Garrett

Nathan is a seasoned design engineer with a deep understanding of how to make a product great. He has been using Solidworks for 20 years and Geomagic for 6 years.