Data Collection for Industry 4.0

Wireless technology is moving onto the shop floor, and its integration in digital gaging is contributing to the next Industrial Revolution.

The internet and modern technology increasingly are shaping the manufacturing industry. Digitalization already has changed our world, and now we are facing another significant change, a new revolution in manufacturing. It’s called Industry 4.0, the networked factory.

The first Industrial Revolution came about with water power and the steam engine, giving people access to a wide range of goods for the first time. The next revolution included electric power, which led to mass production. The third iteration brought about computerization, which led to immense advances in product quality but also required networks, setting the groundwork for further changes. The fourth revolution, Industry 4.0, will facilitate extensive individualization, even further changing how products will be manufactured and sold. 

Today, information is a matter of course, accessible to everyone and no longer a “privilege.” During the third revolution about 35 years ago, the concept of data collection for process control took a major leap forward. This was about the time that a combination of electronic technology and economics allowed gaging to become digital. With a digital signal available, it became possible to transfer information via cable directly from a digital caliper, micrometer or indicator to a data collector. This made it much more practical to make process-control decisions based on statistical analysis.

Until now, checking parts at a gaging station with a hand tool or a dedicated fixture gage connected to a computer via a cable for data collection has been the norm. Today’s hand tools and digital indicators have data output built in, making collecting data easy and cost-effective. These tools also are fast and reliable, and provide a great solution for many process- or quality-control applications. However, they still require that cable from the gage to the computer to facilitate the data collection.

Industry 4.0 wants to take data collection to new levels, monitoring all along the manufacturing process, collecting and storing information from individual measurements to offsets sent to the machines to production results. A lot of data need to be collected. But the collection process must be easy and transparent to the operator without requiring additional work that would delay the manufacturing process.

Technology is ready to take that leap. Just as cellphones and wireless computer peripherals have become common in our everyday lives, wireless technology is moving onto the shop floor. Small transmitters are now being built into digital calipers, digital micrometers and digital indicators, allowing them to wirelessly send data to the gaging computer. Each integrated transmitter in the measuring tool uses slightly different signal coding that allows many gaging stations to communicate to a single computer simultaneously. These transmitters are not that much more expensive than data cables, making the cost more than justifiable when cabling alone won’t get the job done.

With these transmitters, parts can be measured wherever they sit, even in the machine tool, without cables getting caught in the tooling. Plus, the tools provide visual feedback, generating a signal to the operator that the transmission was received and acknowledged by the computer. This happens virtually instantaneously, so it does not slow down the operator. Most transmitters also can be configured to provide a “go” or “no-go” signal to the user based on whether the part is within tolerance.

Another application for wireless transmitters might be when multiple digital indicators are being used on one gaging fixture. Typically, each digital indicator would have its own cable, and some type of interface box would be required to handle multiplexing the signals to the computer. Integrating transmitters into gaging devices eliminates the need for both the cabling and the multiplexers, and it also provides a cleaner-looking gaging station. In addition, the PC running the data-collection software can be triggered by the operator to gather the data from the multiple digital indicators.

Eliminating cables is great, but probably the best application for this wireless technology is right at the machine tool. As the operator measures a part, the data are transmitted wirelessly into the machine tool’s controller and used to help calculate proper offsets, greatly improving throughput and part quality. Out-of-spec parts are virtually eliminated.

At the same time, the data can be stored in the cloud for long-term archiving, also indicating when the part was measured and by whom. In this way, it also can be used for tracking and improving operator throughput.

The next revolution is rising through a combination of digital gaging for accurate shopfloor measurement, unrestricted wireless transmission of reliable data and statistics for process control. Add to this the way machines, robots, inventory and material-handling systems are all talking together, and you’ll see that we truly are getting closer to the fourth manufacturing revolution.