Link to digital version of article in MHI Solutions.
Next generation technologies have long been helping operations increase productivity through their capabilities for greater agility, flexibility and adaptability. Simultaneously, these same systems are keeping workers safer and improving ergonomics. Here’s how.
As explored in the 2021 MHI Annual Industry Report: Innovation Driven Resilience, the organizations that most deftly maneuvered the supply chain landmines of 2020 were those that had invested in digital technologies, such as robotics and advanced automation. Indeed, the inherent flexibility, scalability and adaptability enabled some companies to achieve superior productivity and emerge even stronger and more competitive than before the pandemic made itself known.
Beyond the benefits of resilience, however, automated solutions can safeguard workers in multiple ways. Three of these technologies— robotics, sensors and wearables for ergonomics— are not only helping companies be more agile and their associates be more productive, but they’re also reducing the risk of injuries and fatigue by making tasks less physically demanding, safer and easier.
Here, a look at how these solutions that increase agility, flexibility and adaptability are simultaneously making facilities safer.
Robotics reduce strains, fatigue
While the cost justification of robotic investments is frequently based on the ability to maintain or increase productivity without the need for additional headcount—particularly in an extremely challenging labor market— today, companies are increasingly interested in how their deployment will improve workplace safety.
Joe Campbell, senior manager of strategic marketing and application development at MHI member Universal Robots USA, noted that operations have come to understand that they can increase profitability while reducing turnover by assigning skilled workers to higher value tasks and letting robotics take over the dull, dirty and dangerous jobs.
“Companies have figured out that having a happy, healthy, fulfilled and invigorated workforce is very valuable,” he said, noting that even jobs with minimal tasks and process steps can become tedious and accident-prone.
“Work that requires someone to do the same thing over and over all day, such as welding small parts, picking products or loading machinery, gets boring. By the end of the shift, quality suffers because of it,” Campbell continued. That’s because monotony, like fatigue, can contribute to carelessness that results in injuries.
Multiple advances in collaborative robotic technologies are making them safer, more affordable and easier to implement than ever before. Because they’re loaded with safety sensors, the robots can navigate around and interact with personnel on the floor instead of being secured behind restricted access safety cages. They are also much easier to program, even by operations personnel with limited information technology (IT) expertise.
“We recently introduced our longest reach robot for precision bin picking and machine loading that can manipulate a 25% heavier payload of 12.5 kilograms (27.6 pounds). It’s extremely precise, handles a broad range of parts, and has on-board intelligence that enables it to be deployed within 90 minutes,” noted Campbell. “That ease of programming makes it more accessible to companies that perhaps couldn’t automate those types of jobs before, increasing their operational safety.”
Both Campbell and Rick Faulk, CEO of MHI member Locus Robotics, added that the presence of robots in the workplace is no longer seen by employees as a threat to their jobs, but rather as an incentive to hire on at that company.
“Employees have come to understand that collaborative and autonomous mobile robots (AMRs) make their jobs a lot easier and a lot safer,” Faulk said. “We’ve seen companies actually advertise that they use Locus Robotics as a successful recruiting tool in their hiring process.”
AMRs, Faulk continued, are currently being used to support picking, replenishment and returns, and transport, often by moving a cart previously pushed by a worker. “I’ve toured many facilities where associates say to me, ‘You saved my job with this robot.’ When I ask them to explain, they talk about the previous physical stress and strain of pushing a heavy cart up and down aisles over as much as 15 miles a day, and how tiring that is,” he explained. “But our robots not only do the pushing, but also use sophisticated algorithms that reduce the walking to as little as two to three miles a day.”
Further, AMR deployments typically see a significant drop in accidents, Faulk reported. “When workers are pushing a large, 300- to 500-pound cart around a building, they often can’t see over or around it. That increases their risk of a collision with another cart, a picker in the aisle, or a forklift,” he explained, adding that one Locus customer reported a 70% reduction in overall injuries after replacing manual picking carts with the robots. “With an AMR pushing the cart, workers are hands free and have a totally unobstructed field of view, while the robots are programmed to avoid each other, as well as other obstacles.”
Currently, Locus Robotics continues to incorporate the latest sensors to make their AMRs even safer by expanding their ability to detect and identify differences between objects. When paired with artificial intelligence (AI), Faulk said that the robots will be even more accurate in knowing when to slow or stop. Additionally, the company is experimenting with new materials that can reduce the overall weight of each unit. “Safety is a function of force and weight, so the lighter we can make the robot, the safer it will be,” Faulk said.
Sensors detect, protect workers
In addition to their extensive use in robotics applications, sensors are used widely throughout manufacturing and material handling facilities. In automated and mechanical equipment, sensors trigger a function when they detect a specific object, material or other input/output (I/O) signal. They are frequently deployed for process flow as well as for safety.
Laser scanners are often used to detect the entrance of a person or object into a hazardous area, explained Brian Taylor, business director of safety, sensing and connectivity at MHI member Rockwell Automation.
“They’re commonly used with robotic cells with protective guarding, but the process still requires some degree of human interaction via an opening. For example, a loading or feeding station opening that can’t be protected with fixed guarding because access is required,” he said. “If the scanner detects a person, it stops the machinery.”
Recent advances in laser scanner technology eliminate the false trips that plagued this technology as recently as five years ago, Taylor continued. “They’re much better now at seeing through small particles of dust, water or steam in a food or beverage processing environment, or a welding application. But when they continuously tripped, workers would become frustrated and figured out a workaround to maintain productivity, which obviously is not safe.”
Light curtains are another sensor system used for safety in material handling equipment, such as palletizers. These too have seen significant improvements, he noted, specifically around on-board intelligence and communication capabilities that provide diagnostics data about dust build up, misalignments or other circumstances that are causing false trips.
“The sensors notify maintenance technicians directly that there is a problem. The information is displayed directly on a screen, helping them pinpoint the issue quickly so they can fix it easily,” said Taylor. “Again, this is critical to keeping people productive, so they don’t try to work around the sensor and put themselves at risk.”
Non-contact 2D LiDAR sensors monitor large spaces and provide accurate measurement data from a scanned surface, allowing the device to determine an object’s size and shape. The technology allows openings, such as entrances to robotic automotive processing cells, to be guarded selectively. That is, the sensor can determine if a forklift or an automatic guided vehicle (AGV) is crossing the entrance threshold versus a person, explained Mark Nehrkorn, director of business consulting, safe productivity at MHI member SICK USA.
“We use field set and sculpting to teach the sensor the shape of the vehicle, either with or without a load. If it detects the correct shape, the process continues uninterrupted,” he said. “However, if it detects a worker attempting to enter a restricted area—or an AGV with a worker riding on the side or the top of it—it shuts down the equipment.”
The same technology can be used at palletizer or conveyor loading points to allow the equipment to keep running as a forklift operator performs the pick-up or drop off, but to stop it if a person is detected instead.
Most recently, 2D LiDAR sensors are being utilized within collaborative robots to slow their operating speed when a person is in proximity. “We call this speed and separation monitoring, where the sensor is tracking the person as they approach the robot. Depending on how close the worker is, the robot slows down or stops until the person clears the area,” Nehrkorn noted.
“Often, operations will undersize a robot because of safety concerns, but that can hamper productivity,” he continued. “They could be more productive using a larger robot and still keep their workers safe, as long as they’re smart about their process and the sensor technologies they apply.”
Although not available yet on the market, Nehrkorn added that ultra-wide-band (UWB) technology paired with radio-frequency identification (RFID) tags for localization also offers promise for worker safety. Using at least three transponders to blanket an area via triangulation, the tags (and anything they’re attached to) can be localized within a few centimeters.
“With the proliferation of AMRs and AGVs moving through facilities, these sensors can track their presence in an area shared by personnel and provide that data to the fleet management algorithms that perform path planning and guidance,” he explained, noting that SICK hopes to release this safe localization system next year. “If the people are also wearing tags, as well as forklifts, the system can definitively pinpoint where they all are, which further increases safety.”
Wearables alert workers about unsafe movements
Injuries to warehouse workers often happen as the cumulative result of using improper body mechanics over and over, day after day, said Haytham Elhawary, founder and CEO of Kinetic. But by adding a wearable device outfitted with sensors that monitor, identify, measure and document the wearer’s movements—such as excessive twisting, overextension of the back or improper bending—those actions can be corrected.
“When the device, worn on a belt, detects an improper movement it vibrates to alert the wearer that they just moved in a way that raises their risk injury,” he explained.
Although most workers have been trained to properly lift and move to perform a task, that training likely only occurred once, continued Elhawary. “It’s very rare that a single training will change movement habits. The wearable is like a coach that consistently reminds them to use proper form, and that changes habits.”
The system includes a dashboard that helps managers identify which tasks or areas of a facility are more prone to high-risk movements, enabling more focused training or implementation of ergonomic assist devices. Further, in 2020, many operations deployed the device to reinforce social distancing, as it includes proximity detection and could be programmed to vibrate when two wearers encroached within six feet of each other.
After four years on the market, Elhawary said the device has reduced injuries by between 50% and 60% in facilities such as Pepsi and Iron Mountain. Convincing workers to wear it, he explained, can be an obstacle if employees are concerned about data privacy. “It’s important to explain that the purpose of the device is for their safety, whether that’s in injury prevention or related to COVID-19, and to be very transparent with the data. Share it with employees and consider introducing some friendly competition around reducing unsafe movements to make safety fun, interesting and engaging.”
Looking forward, the device’s future safety functionality can be expanded to provide alerts about a potential collision with a vehicle, such as a forklift. “If a worker is focused on their task, they may not see it coming. Also, we’re working on the ability to alert managers if a wearer slips and falls, and where in the facility they are, so they can quickly send help,” Elhawary noted.
Exoskeletons make lifting less taxing
Companies relying on workers to perform manual, repetitive material handling activities are also beginning to take a closer look at an emerging ergonomic assist solution: exoskeletons (sometimes referred to as “exos”). These lightweight external frames are worn to support the body and enhance its physical capabilities to improve performance while reducing the risk of injury. They can also be designed to physically restrict the wearer from performing movements that might result in a strain, such as overexertion, reaching, stretching, pushing, pulling, bending and twisting.
Dr. Donald R. Peterson, dean of the College of Engineering and Engineering Technology at Northern Illinois University, studies exoskeleton use in material handling. He also serves as the chair of the ASTM International Committee F48 on Exoskeletons and Exosuits, which develops and maintains standards for this technology.
Peterson recently presented the latest advances in exoskeleton design and material handling applications to the members of MHI’s Ergonomic Assist Systems & Equipment (EASE) Industry Group. He said that of the approximately 120 companies developing exoskeleton technology, only four or five are being applied in warehousing.
Different suits offer different advantages and limitations, he noted, so matching the exoskeleton to the task is critical for success. Peterson also stressed the importance of proper training for the wearer.
“The goal is to create an exoskeleton that is user friendly, helps reduce fatigue and assists the wearer to manage what would be considered possibly an unmanageable load. That is, one that’s perhaps light, highly repetitive or unwieldly—not something that’s super heavy,” he explained. For that reason, Peterson believes pick-and-place workflows will be the first area of significant exoskeleton use.
Illustrating that point, the U.S. supply chain arm of grocery store owner Ahold Delhaize recently announced its intent to scale up use of Verve Motion’s exosuits after successfully piloting them to handle millions of lifts in its distribution centers. The suits take less than 30 seconds to put on and automatically adapt to the user and task. Battery-powered, the suit can be worn for an entire shift, including overtime.
The company is deploying more than 250 of the lightweight, powered and soft suits, which reduce the strain on a picker’s back by as much as 40%. According to Ahold Delhaize, that makes each 22-pound item feel like 14 pounds, while associates wearing the suit reported less fatigue and soreness, as well as better posture.
“Selecting product in a distribution center is very physical work, and not only is it very physical, but it’s also critical,” said Chris Lewis, president of Ahold Delhaize USA Supply Chain, in explaining the company’s exosuit expansion plans. “We’re proud to pilot solutions like this one that enable us, and our partners care for the workforce in distribution centers by helping associates reduce fatigue, work more effectively and reduce the likelihood of injuries.”