Reverse Engineering

The role of reverse engineering in modern product design

What is reverse engineering?

Reverse engineering is the process of analysing an existing product’s constituent components in order to understand how it was put together and how it works.

It is often used in research by designers wanting to make add-on or complementary products for an existing product, machine or device as well as to create replica designs – or design knowledge of the source product.

It can also be used in cases where an engineered product or technology is not functioning as it should, so must be ‘deconstructed’ and engineered to understand where the errors and flaws may lie.

Products and systems such as mechanical devices, electronic components, computer software and chemical formulas can all potentially be reverse engineered, making this branch of design engineering an extremely useful technique.

How does reverse engineering work?

In practical terms, a reverse engineering project works backwards from the end-product to determine the design and technology used in its design and development.

The data derived from this process allows the project owner to reproduce or refine the product – or to apply to the development of a complementary product.

What is reverse engineering used for?

Reverse engineering is typically used to gain a deep and detailed understanding of the processes used in the creation, manufacture or development of a product.

The reasons it is used vary widely, from establishing the details of an existing technology or device, to determining the technical aspects of a product that was manufactured in the past, but which now for some reason will be revisited and upgraded.

It should also be noted that reverse engineering may be used in less than ethical ways by certain types of organisation to copy or replicate genuine products or technologies for commercial gain.

• Product improvement (see below)
• Compliance or revalidation processes
• Recovering data and designs lost due to data corruption or IT failures

In most cases, original design drawings are not available, though reverse engineering techniques may be used to convert design drawings into 3D digital data.

Reverse engineering for product improvement

Product improvement is a key driver of reverse engineering projects. For firms involved in product design, development and manufacture, the need for constant development and evolution is simply part of operating in a competitive market.

The main goals of reverse engineering in the context of product improvement are:

• Reducing manufacturing cost
• Refining features e.g. usability
• Improving product performance
• Replacing a product with a new updated version

It is in the nature of product lifecycles that designers and engineers constantly need to find ways to improve both novel concepts and existing products.  To do so they need the data and knowledge to refine and improve a product’s assembly process and working capabilities.

By simplifying a product’s manufacture, its cost can potentially be reduced and its performance improved. It can also be replaced by a newer, more efficient version of the product.

How does reverse engineering work?

The aim of reverse engineering is to develop an understanding of a product and its parts by applying in depth analysis.

With this, the engineer can build a picture of the original design intent of the working parts, their critical tolerances, the materials used and any key functions within the assembly.

Given that efficiency, performance and manufacturing cost are all key goals of the design engineering process, the identification of redundant or obsolescent parts and their subsequent elimination from the product can be just important as the introduction of new parts and features that will enhance the product.

Both of these are objectives of reverse engineering.

Capturing design intent

The first step is to measure components using digital, traditional and sometimes non-contact methods to define the parts. These parts are then modelled up using 3D CAD.

Once the parts are made and the 3D assembly is created, the models can be proofed and tested.

Although in some cases, absolute accuracy in the reverse engineering process is crucial, understanding the design can also reveal areas where a greater tolerance can be accommodated, for example in less critical areas, which in turn may yield potential manufacturing cost savings.

In other cases, a margin of a fraction of a millimetre in measurement can have a major impact on the assembly process, meaning that checking and proofing of specifications and prototyping is critical.

Several CAD tools can be used in accurate measurement:

• Interference checking: to ensure parts can operate with sufficient clearance or are purposely interfering (such as self-tapping screws etc)
• Wall thickness analysis: to ensure that (for example) a moulding has not been modelled with excess wall thickness, potentially leading to problems in moulding further down the line
• Draft analysis: to ensure that surfaces of moulded components have been correctly drafted in the right direction. This also helps to validate the split lines of the product
• Surface analysis: methods such as “zebra striping” can be employed to visualise curvature on smooth surfaces and evaluate surface quality
• Other CAD tools: other tools are used to look at part volume, mass properties and undercut, and help ensure the parts are robust.

Case study: Hornby Hobbies

Our design team had their reverse engineering skills challenged when Hornby Hobbies asked us to reverse engineer their classic Grand Prix racing car shapes.

This involved detailed research and recreation of car body shapes using various measurement methods, photographs and artistic licence – as well as assessing design features by eye.

Reverse engineering projects involving complex shapes like this can be both costly and time-consuming, but the results can be spectacular. Even the smallest detail, such as the beautiful lines of a full-scale racing car are reduced to exquisite, 1/32nd scale replica slot cars.

3D scanning

Where extreme accuracy is needed, 3D Scanning can be used to derive dimensions down to fractions of a millimetre, even at large scale. This is particularly useful when large, organic shapes require ultimate accuracy to be taken from the original.

By taking multiple scans of an object from all possible directions and viewpoints, the 3D scanner collects geometric data that is combined using a common reference system. From the extrapolated data, a digital 3D model can then be constructed.

3D Scanning is used broadly across many industries and is ideal for scanning tangibles, yet can also be used to create intangible designs such as 3D animations and special effects.

For example, objects as large as ships, aeroplanes and even entire buildings have been successfully scanned. At the opposite end of the scale, minute, intricately detailed objects such as dental devices, coins and skin textures can also be successfully captured.

3D scanning applications include:

• Reverse engineering into CAD
• Data input for digital modelling or editing
• Measuring and inspecting parts
• Data archiving
• Virtual reality

Partner Spotlight: Concurrent Design Group

CDT has been working with 3D Scanning experts Concurrent Design Group (CDG) for many years. They have been at the cutting edge of 3D engineering design technology since 1993 and, given their vast experience and knowledge in this field, they are Cambridge Design Technology’s preferred supplier of 3D scanning.

Next steps

If your company has ideas that require cutting-edge design, technology and engineering input, Cambridge Design Technology have the knowledge, experience and creative energy to help you realise your vision – including a full Reverse Engineering and 3D scanning service.

For more information about Cambridge Design Technology and how we can work with you on your next product design project, please call Jon Plumb now on 01787 377106 or email info@cambridge-dt.com

Editors note: this article was originally published in January 2017 and has been completely revamped/republished for accuracy and comprehensiveness.