Reverse engineering (RE) is the process of converting an actual object into a virtual 3-D model. It differs from the traditional engineering process, which starts with virtual design in CAD, and finishes with a machined, molded, formed or 3-D-printed end product. In contrast, RE begins with a physical object and ends with its deduced design dimensions and shape, for the purpose of maintaining, recreating, adapting or improving this product (or system or assembly). The physical object can be measured using 3-D measurement technology such as CMMs, laser scanners, structured light digitizers, or industrial CT scanning. Once the object has been measured, a RE software will be used in order to convert the 3-D measurements into the final reverse-engineered model.
Reverse engineering has a multitude of applications. It could be used for legacy parts preceding computer technologies, making copies of a unique object, building a scale model, designing an object that must fit around an existing one, or repairing a cast mold for which no digital information exists.