Coming to a factory near you: Man-machine hybrids

May 07, 2015

In March, employees at Audi’s Neckarsulm manufacturing plant began using a small exoskeleton that allows them to sit down on the job. The Chairless Chair is a powered lower limb posture support device that transfers the weight of the wearer to the floor. It was developed by Noonee, a Swiss start-up, and is designed to relieve strain during long shifts filled with repetitive tasks, the kind common on industrial lines. The refrain among workers: It’s about time.

Occupational safety stats for the manufacturing sector have improved in recent years, but the numbers remain grim. There were 476,700 nonfatal occupational injuries and illnesses in the manufacturing sector in the U.S. in 2013, which is the latest year for which data is available from the Bureau of Labor Statistics. Many of those were repetitive strain injuries caused by forceful exertion over time, such as hoisting or shifting loads. Best estimates for claims related to all repetitive strain injuries put the cost to industry at $20 billion per year, not counting the high costs of lost productivity. Protecting workers makes financial sense, and though robots are often seen as a threat to industrial labor, the new class of wearable robotic devices may be the best bet to aid a workforce long beset by injuries and physical discomfort.

The Chairless Chair is lightweight and low-cost. Worn on the back of the legs and fastened with belts to the hips, knees, and ankles, two surfaces support the buttocks and thighs while struts made of plastic hug the contours of the leg. The struts are jointed at the knee and can be adjusted to fit a large range of body sizes. The hydraulic device uses a lightweight variable damper to hold a desired posture and support the user’s weight. When inactivated, a worker can freely walk around while wearing it.

"It helps us to enhance our employees’ well-being and maintain their health over the long term," says Audi’s Board of Management Member for Production, Dr. Hubert Waltl. "At the same time, an ergonomically optimized working environment promotes more productivity and even better quality."

The need to help workers cope with loads and body stresses isn’t confined to manufacturing. There were 203,000 nonfatal occupational injuries and illnesses in the construction sector in 2013. Unlike line workers, most construction workers are mobile throughout their shifts, and sitting isn’t often an option. Russ Angold, CTO at Ekso Bionics, a pioneer in untethered exoskeletons for rehabilitation, recently announced an unpowered exoskeleton suit targeting the construction and industrial spaces.

Like the Chairless Chair, the Ekso Works transfers the weight of a load to the ground. But Ekso’s device goes a step further. A heavy tool can be attached to a sprung arm, effectively rendering it weightless to the operator. A system of counterweights balances the user, and after years of replicating the mechanics of walking through work on their powered suits, Ekso’s engineers have created the Works to conform to a natural gait.

Carnegie Mellon University’s Steve Collins and North Carolina State’s Greg Sawicki published a paper in the journal Nature in March describing what they call a walking assist clutch. The small device clamps around the calf like a pair of sock garters. A mechanism near the heel catches and releases a spring at precise moments during the gait cycle. The unpowered device makes walking 7% more efficient, which could keep nurses and doctors lighter on their feet for longer.

A robotic future that displaces workers may be in the offing, but robots and exoskeleton devices are also helping workers avoid injury and reduce fatigue on the job. In the medium term, the industrial workforce may become populated with man-machine hybrids. And if manufacturers can increase efficiency while keeping workers on the clock, then these new devices may actually stave off the threat of automation in many industries a while longer.

Source: ZDNET