As states reopen to one degree or another and try to get back to some normalcy, more manufacturing facilities are bringing their workers back. Health experts have argued that precautions need to remain in place, however, or else we risk coronavirus cases spiking again. Without widespread testing on a national level, manufacturers are left largely to their own devices to ensure safety of their employees as they get back up and running.
Fortunately, there is no shortage of innovative ideas. Several companies have been developing new technologies to help, and also emphasizing how old technologies could fit the new reality. Social distancing could be with us for quite some time. The distance between two people—as well as the duration of their proximity—significantly influences the risk of infection. But what’s the best way to make sure that factory workers are maintaining a physical distance from one another?
Siemens sees real-time location systems (RTLS) as a helpful technology for maintaining a certain distance between employees—and also one that will be of long-term benefit once social distancing is no longer a requirement.
RTLS is similar to RFID technology but uses active tags, meaning they have an energy source included that enables them to transmit signals on their own. The signal from the transmitter moves out to at least three antennas called gateways. Depending on how long it takes for the signal to reach the antennas, triangulation enables the technology to figure out where the device is.
RFID, on the other hand, uses passive tags. It has to move in proximity to an RFID antenna—within a couple inches, typically—to get information from the tag. RFID is best used when you know where something is, but you don’t know what it is, explains Jeff Snyder, product manager for industrial identification at Siemens Industry. For example: “You have a raw material that just got delivered to a processing machine, and you want to make sure it’s the right material before you introduce it into the process,” he explained. “RFID can verify that it’s the correct material.”
RTLS is better suited when you know what you’re looking for, but you don’t know where it is, Snyder points out. Maybe you’re making turbine blades in a large facility, where the blades travel from one CNC station to another. One way to track those blades as they make their way through the process is with RTLS.
“A big advantage of RTLS is that its location resolution is down to a foot,” Snyder said. “If you have time-sensitive goods, it can also help you understand where the delays are.”
RTLS can track a forklift very accurately, for example, enabling you to optimize routes for that forklift. With RTLS, you could identify where a pallet is at all times. “What if we put RTLS tags on people to monitor their movement?” Snyder posed. “That kind of sounds like social distancing.”
Social distancing, of course, is high on the list of what manufacturing facilities will have to maintain if they’re going to keep their employees safe. “They have to figure out how to fix social distancing problems,” Snyder says. “Part of that is know where they’re taking place.”
There are several questions that need to be answered along the way: How do we monitor interactions? Is it a quick pass in the hall or did they stop and chat for 15 minutes? Do I have operations that just inherently bring people too close together? How can I make changes and have any idea that they are good changes?
Siemens advocates that employees wear RTLS transponders—on a safety vest, for example—to help answer these and other questions. “There’s going to be concentrations of the social distancing violation. Maybe there’s an aisleway that causes problems. Maybe there’s the person who’s trying to set up the bowling league for next fall,” Snyder comments. “There are things that can be quickly and easily addressed through hotspot analysis. The changes customers can do once they have actionable data is going to be fairly simple in a lot of cases.”
The transponders will enable distances to be determined down to a foot, ensuring that employees are maintaining safe social distances. The tags can be set up to start a timer when employees get within 6 ft of one another, and a company can decide how long that timer goes before calling it a violation.
The RTLS monitoring software also creates a history of employee movements, so it can be used for contact tracing if an employee does become sick. “You can see all the distance violations that that tag ID had,” Snyder says.
RTLS location information also allows employee movements to be analyzed and optimized, including at shift changes, where transitions might particularly need to be optimized.
Ultimately, it’s a smart investment, Snyder contends, because once the pandemic has passed, the technology will already be in place for a wide variety of other uses throughout the facility. “Once you make this investment in the RTLS hardware, you can use it for other things,” he says. “It’s not a one-time use.
Another player in real-time localization also advocates the technology for social distancing measures. In this case, German supplier Kinexon Industries has developed Kinexon SafeZone—the core element being a wristband that actively warns the user as soon as the minimum physical distance to another person has been compromised. It is a large-scale industrial system that requires no infrastructure. Optional software also helps companies trace chains of infection and take strategic action.
SafeZone comes in two versions. A basic version for real-time warning consists of the Kinexon SafeTag, a wearable with an ultra-precise sensor that warns the user, audibly and visually, when the physical distance has been compromised and the contact duration exceeds a specified time. It uses ultra-wideband (UWB) technology.
The extended version for data protection-compliant tracking enables the storage of relevant data relating to critical contact events, allowing for analysis. Potential cases of infection can then be quickly identified using the relevant sensor IDs.
“We want to help customers secure jobs and protect the health of their employees,” says Alexander Hüttenbrink, co-founder and managing director of Kinexon. “Instead of complete quarantines, which ultimately means a standstill in the company, we enable prevention strategies by maintaining minimum distances and precisely tracing infection chains.”
Keeping in the wearables vein, ProGlove has upgraded its Mark family of wearable barcode scanners and ProGlove Connect app for Android to enable proximity sensing for production line workers.
“Our key customers are sharing with us the challenges they’re facing as they rethink and retool to restart operations,” says Andreas Koenig, CEO of ProGlove. “We faced similar challenges as we reviewed our own processes for safety and efficiency. It is our natural tendency, as humans, to want to go back to doing things the way we did them before. However, it’s not possible. Proper social distancing is now key to a successful return to work.”
The new ProGlove Connect Proximity app provides an additional layer of feedback on an Android device alone or when paired with a ProGlove Mark barcode scanner that rests on the employee’s hand. Workers coming within close proximity of each other are alerted through audio sounds, optic LED light, and haptic vibration signals. This is important in a busy or noisy shopfloor environment where an Android alert alone in a pocket could be easily overlooked.
“We tested the Mark upgrade in-house and it works beautifully. We’re now rolling it out on our own assembly line,” notes Konstantin Brunnbauer, vice president of production for ProGlove. “For my team, it is easy to want to fall back into old patterns of working together. But with this extra reminder, we can maintain safe distance.”