Reverse engineering

It is a very common question asked, what is reverse engineering?

In mechanical engineering, the term reverse engineering (often abbreviated to RE) is used to summarise the process of reconstructing an existing object. When designing an object from scratch, an engineer will draw up a design specification and produce drawings from which the item is constructed.

Conversely, with reverse engineering, the design engineer starts with the final product and works through the design process in the opposite direction to arrive at the product design specification. During the process, vital information about the design concept and manufacturing methods is discovered.

The process of reverse engineering begins by gaining dimensional information of the object via 3D scanning, whether it is a mechanical component, a consumer product or an ancient artefact.

Reverse engineering involves acquiring three-dimensional positional data in the point cloud. There are many ways of gathering valuable dimensional information about the product, but using an accurate 3D measuring system is paramount. The accuracy of the data captured will impact the quality and deviation of the Reverse Engineered model when compared to the original.

Physical Digital uses the globally-recognised GOM 3D structured light scanning systems, which offer highly-accurate, traceable and repeatable measurement. The surface data captured is then passed to our in-house design team to establish the original design intent of the object.

What is Reverse Engineering used for?

Reverse engineering enables the duplication of an existing part by capturing the component’s physical dimensions, features, and material properties. There are a wide range of reasons for reverse engineering an object, including:

Legacy Components – For many components that were designed and manufactured years ago, there are no existing 2D drawings or 3D CAD data from which to reproduce the object. Here, reverse engineering is a vital means to gain the information to recreate the product.

Original Equipment Manufacturer (OEM) issues – If the OEM is no longer trading or has lost design measurements, then Reverse Engineering will supply the vital product information to continue manufacturing of that object.

Design Development, Part Testing & Analysis – Through reverse engineering, a 3D product can be quickly captured in digital form and remodelled or analysed in order to achieve improved design iterations.

Competitor Analysis – Any organisation can analyse competitor products through reverse engineering.

Bespoke and Ancient objects – Where there is no information about the dimensions of an object except for the physical item itself, the quickest and most reliable way to reproduce it will be by reverse engineering. Where a product is organic in shape (not a standard geometry such as cuboid or cylindrical), designing in CAD may be challenging as it can be difficult to ensure that the CAD model will be acceptably close to the sculpted model. Reverse engineering avoids this problem as the physical model is the source of the information for the CAD model.

Modern manufacturing – methods such as Additive Manufacturing rely on reverse engineering.

Digital Archiving – Museum pieces and historic artefacts can be captured through 3D scanning, then reverse engineered and the resulting CAD data can be held in case of any future damage to the object or any need to reproduce parts of the item.

Time and cost-effective way to produce models and products

The process of reverse engineering is particularly cost effective if the items to be reverse engineered represent a significant financial investment or will be reproduced in large quantities. Another advantage presented by reverse engineering is in compressing the product development cycle. In a highly competitive global market, manufacturers constantly strive to shorten lead-times to bring a new product to market. With reverse engineering, a 3D model can be quickly captured in digital form and remodelled if necessary or exported for a variety of manufacturing methods such as Additive Manufacturing, Vacuum Casting or CNC machining.

How to capture the data for Reverse Engineering 

Representing the geometry of the part in terms of surface points is the first step in creating parametric or free-form surfaces. A highly accurate and dense polygon mesh is created from the point cloud using the native measurement software or a dedicated reverse engineering software.

The added benefit of a photogrammetry system provides even greater certainty of the data captured for larger objects, such as entire aircraft or boats. Photogrammetry is a separate metrology system designed to capture reference points using multiple digital images, using a verified DSLR camera. The GOM 3D scanning system can use these reference points to extend the potential scanning area, which means it is possible to capture larger items, which can then be reverse engineered.

Reverse engineering process

Depending on the downstream application for the CAD model, different types of surfaces can be created. For example, this could range from producing a fully parametric CAD model which can be easily modified, which is likely to be required when undertaking redesign or optimisation. Compared to where the part is going to be remanufactured or analysed, when a clean representation could be employed.

Through the use of inspection software, analysis of the CAD model is performed and reported to the Client. This highlights the maximum deviations between the scan data and CAD model and documents that the requirements of the specification have been met.

Why do we use Computer Aided Design (CAD)? 

Through the use of various CAD and reverse engineering software, we can create accurate data for manufacturing, analyse how it will perform and improve existing designs.

CAD is used to create two- or three-dimensional (2D or 3D) graphical representations of physical objects. In product and industrial design, CAD is used mainly for the creation of detailed 3D solid or surface models, or 2D vector-based drawings of physical components. However, CAD is also used throughout the engineering process from conceptual design and layout of products, through strength and dynamic analysis of assemblies, to the definition of manufacturing methods. This allows an engineer to analyse design variants, to find the optimal design for manufacturing while minimising the use of physical prototypes

One of the first things customers would like to know when they contact Physical Digital is how much does 3D scanning cost?

The answer is that the cost of 3D scanning can vary greatly from project to project and there are many factors that need to be taken into consideration when quoting. The team at Physical Digital® team assess the following to provide an accurate cost:

Scale of object:

Physical Digital have the capability to capture large-scale objects in high-resolution, but the level of detail required downstream for the project will affect the process used, time taken and overall cost. Photogrammetry is often used as the initial data capture method to generate a highly-accurate point cloud which is referenced by the ATOS Triple scan sensor. This will help to reduce deviation on large-scale projects such as aircraft.

Complexity of the object:

Physical Digital deliver their 3D scanning services using world-renowned GOM metrology equipment, which works by line of site. This means that it captures highly-accurate surface data by projecting a phase-shifting fringe pattern using 3D structured blue light onto the surface of your object. The more complex and detailed the surface, the more scans and time it will take to capture the data, influencing the overall cost of the project.

Number of components to be scanned:

Whilst we often scan single components, for multiple-part scans we have an automated measurement facility which offers a significant cost benefit as a batch measurement solution. Where required, our in-house design team can design and manufacture bespoke or modular fixtures to enable even faster scanning of these parts, which can greatly reduce the cost per object.

Location:

When quoting for a project we will take into consideration where the 3D scanning will take place, i.e. if you will be sending the part/s to be scanned at our facility in Surrey, or if you require our mobile 3D scanning services to be delivered on-site, at a location of your choice. Many of our customers see the benefits of on-site scanning as it reduces the overall down-time of the part, subsequently reducing the length of the project.

Deliverable:

We can provide the raw scan data, however we are also able to provide you with in-depth inspection reports or our expert in-house design team can reverse engineer a surface model into CAD and provide manufacturing drawings. The complexity of the object will directly affect the time it will take to be reverse engineered which will of course affect the price.

Downstream use of the data:

Considering what the data will be used for is also an important consideration when quoting on new projects.  For example if the part is being used for special/visual analysis then the resolution can be reduced speeding up the measurement process and therefore reducing the overall project cost.

Physical Digital is the largest and longest-established approved GOM service provider in the UK, providing high-accuracy, fully traceable data to a wide variety of industrial sectors and beyond. Our experienced team will work with you to tailor a measurement solution to suit your requirements, whether that is to be completed at our facility in Surrey or on-site at your place of work.

To find out how Physical Digital’s 3D scanning services could support your project, contact us today on +44 (0) 1483 750200 for a no-obligation 3D scanning quote or to chat with one of our team to find out more.