What is reverse engineering and why do you need it?
Sometimes you need to go beyond Digital Modeling (polygonal or rapid NURBS dumb solids) into design intent. That’s when Reverse Engineering is required. Reverse engineering uses an existing physical object, digitally captured via 3D scanning, but provides more than just a CAD model of the design. Reverse engineering takes into account the intended design of a physical object. Because every manufactured part or object varies somewhat from its original intended design, reverse engineering is used to identify, analyze and correct these imperfections.
Not surprisingly, reverse engineering is also frequently used to capture a design and then improve upon it. How do we determine when a 3D scanning project falls into the category of Reverse Engineering as opposed to Digital Modeling? When should you opt for reverse engineering, even though it may be more time consuming and possibly more expensive?
We usually look at several factors in order to advise our clients:
Is the shape organic or geometric? Will you be rapid prototyping a hand carved table leg, or using the scanned model or an airplane wing component for CFD analysis? In the first example a simple digital model will probably work just fine; however in the second example, we would recommend a fully reverse engineered model.
- Desired File Output
Digital modeling is recommended for rapid prototyping or visualization purposes. However, if you need to bring your files into a parametric modeling software for analysis or redesign, then reverse engineering is a must. When you need more than that, either for redesign purposes or for importing models into analysis programs, we generally recommend reverse engineering. Reverse engineer, means that we bring the 3D scanned files into parametric modeling software.
- Four types of models work with this type of software:
- A Rapid NURBS ‘dumb solid’ NURBS surfaces are wrapped over the polygonal mesh. This wrapped surface model is smoother than a polygonal model and generally contains no regular geometric features. This type of NURBS model can be brought into parametric modelers such as SolidWorks. However, it has no parametric history – which is why it is called dumb.
- A Hybrid Model is a polygonal model that has been converted in a rapid NURBS surface model and that also uses some traditional solid modeling techniques. It is commonly used when basic geometric features, such as holes & edges, blend with complex organic contours, such as a machined casting.
- A Hybrid ‘dumb solid’ model is a more fully developed model than a Rapid NURBS, but not quite as time consuming as a reverse engineered parametric model. Unlike a Rapid NURBS, which is essentially a wrap around a polygonal frame, the hybrid dumb solid contains some geometric features such as holes, planes, and radii but these features still have no parametric history.
- A Parametric Model is a fully reverse engineered model with a fully functioning feature tree, which allows for complete redesign if desired. These models are built as if they were engineered from scratch, making them perfect for the reverse engineering of legacy parts and redesigns.
We specialize in Tool and Die Reverse Engineering and Reverse Engineering of Legacy Parts for Modernization