Metrology in Industry 4.0

Naturally, any technology-, science- or software-based field is expected to advance greatly in our lifetime. One only has to consider Moore’s law to see the implications. As is commonly known, even the tech that we carry on our person these days is more powerful than the computers used by NASA to put a man on the moon. All of this is, of course, only possible because of accuracy in manufacturing: “You can only make as well as you can measure,” as famously stated by Sir Joseph Whitworth. With metrology advancing to the atomic level of accuracy, and the advent of Industry 4.0 and The Internet of Things (IoT), where is metrology headed?

Forbes defines the fourth industrial revolution as taking “what was started in the third with the adoption of computers and automation and enhance it with smart and autonomous systems fuelled by data and machine learning.” With the potential prospect of a completely automated manufacturing process, including autonomous quality control/assurance systems, much is left to speculate on what the factory of the future will look like. But there are plenty of advanced systems available today that show us where the world of metrology will be in the future. Exact Metrology shared their perspective with us:

“Industry 4.0, to encapsulate the concept, seeks to fundamentally alter the interaction between worker and machine. The integration of manufacturing, IT- and cyber-systems, including security, plays an ever-growing and evolving role in the manufacturing world at all machine shops today, whether they be a family-run mould shop, a 100-person contract manufacturer or the production department at a major transmission builder.”

One of the latest advancements in the field of metrology is with the introduction of industrial CT scanners. Whether a component is made of metal, plastic or a composite material, a CT scan can analyse the internal structure of a component, which is not possible with optics- or touch-based scanners such as lasers, light, or probe scanners. Some specifics from Exact Metrology on the capabilities of different scanning methods:

“-laser scanners are typically mounted on a robotic armature with an optical scanning system; can work in an area up to 18 feet in diameter and produce data at a rate of nearly 500,000 points per second

-white/blue light scanners, mounted on a tripod or robot, capture more than 18,000,000 points per second; in a single shot, white light scanning can take measurements in an area from less then a square inch to several square feet

-CT scanning allows the measurement of internal structures of parts by generating a voxel cloud from a number of two-dimensional x-ray pictures which can be converted to point cloud data”

As each method advances in accuracy, adaptability and mobility, one of the key attributes for the future will be the ease of integration. Automated conversion from scan to CAD file is just one way in which the operator will be separated from the machine. Exact Metrology gives us an example with a 3D scanned automotive panel and engine block:

“The 3D scan can produce a dense point analysis for comparison of an “as machined” image to the pristine “as designed” CAD file. The scanning software can also render what we call 3D CAD comparison and deviation plot, which are significant steps up from the CMM or optical gauge capability. Conventional first-article inspection reports are also possible output from the scanning software technology today. Using the latter, also known as a 3D colour map, which immediately visualizes the scanned object against the nominal design and is available almost immediately post-scan.

Over time, SPC data can be developed as colour maps or simply detailed, tabular data to track the performance of your machines in a preventive or predictive maintenance mode, as well as for OEE indexing.”

The precision of these technologies is ever increasing, currently being as accurate as 0.0127mm. This rivals regular CMM systems, though it does not make them obsolete. In fact, a major advantage of modern systems is their adaptability: the use of robot arms with interchangeable attachments means that, when required, a touch probe may be fitted with optical trackers. As Exact Metrology states, “This gives the shop the benefits of both high-density scanning and high-precision point measurement on the same part.”

As we approach The Internet of Things, cybersecurity will become a major concern in every aspect of life. With increased automation and digitisation in a manufacturing context, this will become a major component of metrology as well.

There will be a need to measure as long as there is a need to create. But perhaps in the future, most of this process will not be operated by humans anymore.