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These 'Bots Are Made for Walking

Stephen Piazza

Age of the Exoskeleton

2013-09TechnoPiazzaF3.jpgClick to Enlarge ImageAlthough the first Lokomat was introduced two decades ago, researchers are still just beginning to explore the ways robots can help injured patients walk again. If robotic exoskeletons do become a fixture in the gait rehabilitation clinic, the role of the physical therapist is likely to change. Early on, some therapists worried that the engineers’ goal was to replace them with robots, but it is now clear that robots have great potential for freeing therapists to do what they do best. Robots do not mind the drudgery of working with patients on repetitive motions, which allows the therapists to concentrate on helping patients master the more intricate and varied tasks of daily living.

As robotic gait therapy matures, it will need to become more versatile. Walking on a treadmill is an excellent first activity, but patients need to do more than put in long hours walking at a constant speed in a straight line. Adding turns, stops and starts, and obstacles such as curbs will make rehab training more practical and more useful. Ultimately my colleagues and I hope to see robots help patients regain the ability to walk freely on normal ground. Newer, more compact and battery-powered exoskeletons that can operate away from the treadmill and even outside the clinic should help meet this objective. Eventually robots may be used to train patients to perform more complex everyday activities, such as climbing stairs, negotiating ramps, and getting into and out of cars and bathtubs.

“Robotic therapy” may evoke images of a powerful automaton yanking on one’s limbs, but the reality will be a lot less intimidating. In 2040, barring unforeseen circumstances, I will be 72 years old. By then there will be 80 million other Americans age 65 or older, twice the number of older adults in the United States today. I hope that I won’t have any serious mobility problems to overcome, but it is inevitable that many of my fellow elderly will be dealing with the consequences of strokes, limb amputations, joint replacements, and falls. And it is very likely that robots will be helping.

The public has already grown accustomed to smartphones, smart appliances, and even smart cars. The robots we encounter in physical therapy tomorrow will not be very different from smart versions of the exercise machines we use today. We look to the heart rate monitor on an exercise bike to keep from slacking off or overtaxing our cardiovascular systems. Rehabilitation robots will be used in a similar fashion to get a customized workout for the nervous system. My expectation is that my generation will not only welcome robotic therapy assistants, we will demand them.


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