What happens when a specialized, expensive piece of machinery breaks and you don’t have the original drawings or models of the product in order to diagnose the problem or fix it? Or what happens when you need to create new molds, models or parts for an older piece of machinery and you don’t have any design documentation (drawings or CAD models) with which to work?
In both of these situations reverse engineering that existing piece of equipment or machinery might be the best—and least costly—course of action. By capturing data from existing physical objects and feeding that data back into the digital model, engineers can manipulate and redesign—if necessary, in order to either reproduce a product or fix a problem with an existing product.
The reverse engineering process requires hardware and software that works together; the hardware is used to measure the object and the software reconstructs it into a 3D model. The physical object can be measured using 3D scanning technologies, such as coordinate measuring machines (CMM), laser scanners, structured light digitizers or computed tomography.
Several things have happened to widen the use of reverse engineering. The entry point cost of reverse engineering has declined, the hardware has gotten smaller and easier to use, the software has become easier to use, and the process of converting and managing scanned data simplified.
Reverse engineering in the palm of your hand
There have been huge advancements in 3D scanning technology, in particular in non-contact optical surface digitizers. These scanners or digitizers are more portable and affordable and are capable of capturing points faster and more accurately. Their portability is a big benefit when large equipment in the field needs to be digitized.
Handheld laser scanners can capture tens of thousands of points per second with a high level of accuracy and are widely used for a range of engineering applications. Handheld scanners can be used in any location to digitize 3D surfaces in real time and then input that data directly into CAD systems, further speeding the reverse engineering process.
As the hardware has improved, the demand on geometric modeling technology and software tools capable of processing large amounts of data points and converting them into useful forms, such as non-uniform rational B-spline (NURBS) surfaces, has also increased. Many leading reverse engineering software packages are now integrated with CAD tools, so users don’t need to be trained on new systems.
Auto-surfacing tools that automatically convert point clouds into NURBS surface models have also been developed and implemented into commercial software tools. These NURBS surface models converted from point cloud data can be used in some engineering applications, such as maintenance, repair and overhaul (MRO, part inspection and measurement, and fixture calibration.
Scientists reverse engineer a jellyfish
In an effort to better understand how human heart tissue works, scientists at Harvard have reverse engineered a jellyfish, building an artificial one from silicone and rat cells. Sounds far-fetched, but scientists recognized similarities in the way jellyfish move, using a muscle to pump through water, and the way the human heart pumps blood.
So how does reverse engineering fit into this story? Basically, the team needed to figure out how jellyfish work; how to build each component and how they all fit together, including things like how the muscles are arranged, how the body moves, and how the fluid both inside and outside their bodies effects movement.
One of the lead researchers, Kit Parker, says that the team discovered something interested immediately: the electrical signals that the jellyfish uses to coordinate the pumping are exactly like that of the heart. The goal of the study ultimately is to learn how to build human hearts, but in the shorter term the researchers think the fake jellyfish could be used to test drugs and see if they help improve pumping.