OptoComb, a revolution for automated inspection & the manufacturing industry
Only about 20% of the inspection process is automated
The manufacturing industry is now focused on a future guided by the concepts of “Industry 4.0” and “Smart Factory” that aim at a radical shift toward an integrated factory automation and rationalization. Most manufacturers have quickly recognized the limitations of human operations and have worked tirelessly to automate their manufacturing processes: machining, processing, convey and assembly. Inspection however sill lags behind, and well into this 21st century, many factories solely rely on the human eye to carry out this essential process.
Why are the dimensional and visual inspection processes not automated? This is because the human eye has unique capabilities that are hard to match: a high acquisition speed, a large field of view, a large dynamic range, a robust operation in various light environments and the possibility to detect features down to the 100 µm range. Although automated visual inspection has been massively introduced for the manufacturing of very small, low-profile parts like semiconductor chips, this is not the case for larger objects such as the many cast, forged and machined parts one finds in the engine or transmission of a car. In order to implement a robust and automated inspection process on such manufactured parts, it is actually necessary to measure shape irregularities at high speed, with high accuracy, while being completely impervious to the ambient light of the factory floor. However, in-line measurement equipment with those high requirement has not been available until now. As a result, only about 20% of manufacturing sites rely on automated processes for the inspection of medium and large parts, which has led to major issues for manufacturers.
OptoComb 3D scanners by XTIA, a breakthrough for automated inspection
There are several obstacles to automating inspection. The first and foremost is the required inspection speed. On the manufacturing floor, many parts have a takt time of about one minute that puts a heavy burden on all manufacturing processes. To implement the inspection process, there are two ways the dimensions of a part can be inspected, with drastically different performance regarding speed: contact and non-contact inspection. While the contact inspection method has a wide range of applications, its measurement speed is typically limited. It is thus used for sampling inspection, but it is not suitable for a total inspection of all manufactured parts. This is where non-contact inspection comes into focus. Conventional non-contact inspection methods that allow for defect detection typically include light triangulation and the white-light focus or white-light interferometry scanning method:
Unfortunately, on one hand, triangulation suffers from shadowing effects when applied to uneven and complex structures due to the angle between its incident and reflective light. On the other hand, white-light interferometry has a very short working distance and a very shallow depth of focus, which makes it unsuitable for inspection of large and medium parts with highly complex shapes.
This is where the OptoComb 3D scanners by XTIA come into play. The OptoComb inspection method uses a unique laser that presents a coaxial configuration, meaning that both its incident and reflected light beams propagate along the same axis: as a result, this method is not hindered by shadowing effects. In addition, the coaxial configuration together with the long working distance of the OptoComb provides the full 3D profile of the most complex parts such as cylinder heads, valve bodies, etc. where other methods fail.
4 advantages of OptoComb 3D scanners by XTIA
① Complex shapes and features
Thanks to their unique coaxial configuration, OptoComb 3D scanners by XTIA circumvent the shadowing effects that hinder traditional optical sensors. With their long working distance, OptoComb scanners can thus probe objects deep into holes and slits and provide the full 3D profile of the most complex parts: cylinder heads, valve bodies, rotors…
② Fast & automated
OptoComb 3D scanners can acquire up to 500,000 data points per second. This leads to a scanning process drastically faster than traditional contact measurement methods. Our scanners can thus meet short cycle time and they are routinely integrated in-line for the automated inspection of 100% of parts.
③ Micrometer resolution
With their unique measurement scheme, OptoComb scanners can achieve such a performance while reaching a resolution as high as 1μm along the laser axis. This is of course essential for dimensional inspection, in a context where manufacturing processes are becoming more precise while design tolerance are getting tighter. Furthermore, it can be leveraged to optimize the visual inspection process. Unlike traditional contact inspection methods, OptoComb 3D scanners can detect and provide quantitative information on a large range of 3D microdefects such as dents, scratches, particles, burrs and more.
④ Impervious to ambient light
Furthermore, as opposed to a lot of optical sensors out there, the interferential detection scheme of OptoComb 3D scanners prevents the system from being affected by the ambient light. They are thus the ideal solution for the inspection of both matt and shiny parts on the manufacturing floor whatever the light environment.
Some OEMs using OptoComb 3D scanners on their manufacturing lines