Reverse engineering (RE), the process by which an existing item is identically reproduced, becomes necessary when a physical prototype exists, but an accurate geometric data file of the part does not.
In order to recreate the existing part, a computerized (CAD) model of the part must be drawn or otherwise acquired. This CAD file provides the coordinates of multiple points on the product surface, which is then used to develop the drawing of the product for redesign or manufacturing. This data may then be analyzed within the CAD program or exported to a machine capable of rebuilding the new design or its tool, such as rapid prototyping (RP) or rapid tooling (RT) equipment. Although the automatic regeneration of the CAD model without the time-consuming use of CAD software is merely a single step in the RE process, it has become the focus of the RE community due to the ongoing pursuit to acquire more accurate 3-D data in a faster and less expensive manner.
Collecting accurate geometric data of any manufactured part is complicated by the numerous surface curvatures and odd shapes associated with manufactured products. Inaccurate data can be obtained using handheld devices such as calipers, but the time required to gather sufficient quantities of this data becomes extensive and the results become susceptible to inevitable human error. Until the advancement of automated RE technologies, acquiring substantial amounts of data with acceptable precision was nearly impossible.
The rapid advancement of computer technology has given rise to numerous automated RE methods that utilize a broad range of technologies to acquire data. These technologies provide extremely precise 3-D geometric information of nearly any item. Two of these technologies, contact scanning and laser scanning, have become increasingly popular in several manufacturing industries due to their speed, accuracy and relatively low cost.
The term “reverse engineering” includes any activity you do to determine how a product works, or to learn the ideas and technology that were originally used to develop the product. Reverse engineering is a systematic approach for analyzing the design of existing devices or systems. You can use it either to study the design process, or as an initial step in the redesign process, in order to do any of the following:
Observe and assess the mechanisms that make the device work
Dissect and study the inner workings of a mechanical device
Develop the part or product geometry in a CAD model from the actual part or product
Compare the actual device to your observations and suggest improvements
Reverse engineering may also be necessary if alternative methods of obtaining technical data are more costly than the actual reverse engineering process. Generally, many products are protected by copyrights and patents. Patents are the stronger protection against copying since they protect the ideas behind the functioning of a new product, whereas a copyright protects only its look and shape. Often a patent is no more than a warning sign to a competitor to discourage competition. If there is merit in an idea, a competitor will do one of the following:
Negotiate a license to use the idea
Claim that the idea is not novel and is an obvious step for anyone experienced in the particular field
Make a subtle change and claim that the changed product is not protected by the patent
Reverse engineering initiates the redesign process, wherein a product is observed, disassembled, analyzed, tested, “experienced,” and documented in terms of its functionality, form, physical principles, manufacturability, and ability to be assembled. The intent of the reverse engineering process is to fully understand and represent the current instantiation of a product.
Before you decide to re-engineer a component, be sure to make every effort to obtain existing technical data. For example, you can proceed with reverse engineering if replacement parts are required and the associated technical data is either lost, destroyed, non-existent, proprietary, or incomplete.
Consider the following ethical uses involved in reverse engineering:
Do not reverse-engineer parts if the procurement contract of the component prohibits reverse engineering.
Remember to perform reverse engineering using only data that is part of the public domain.
If you intend to perform reverse engineering, be sure that you:
Do not have access to proprietary information
Have not been recently employed by the OEM, or had access to proprietary information
Do not visit or tour the OEM’s place of business
Maintain complete documentation of each component you reverse engineer so there is a record that will stand as proof in court that you have performed reverse engineering lawfully