Robots to the Rescue
Science is often about inspiration. “Aha!” moments can result in ideas that can help solve problems or interpret situations differently. For Sunil Agrawal, professor of mechanical engineering and rehabilitative medicine, the inspiration to design innovative robots and human-machine interfaces that enable people with impairments is close to his heart.
“Having seen my father suffer from Parkinson’s disease in his late years, I have observed, firsthand, the debilitating effects of neurological disorders on gait and motion functions,” he confides. That very personal motivation has led to pioneering work in robotic exoskeletons and robotic interfaces to help adults and children move more easily or retrain their bodies to regain lost function. The work has resulted in 10 new U.S. patents in the last five years, with an additional dozen currently under review.
“Robotics can help people who suffer from Parkinson’s or Lou Gehrig’s disease maintain muscle health. For children born with medical conditions such as cerebral palsy, spina bifida, and scoliosis, robotics can help alleviate the effects of these diseases on their lifespan,” says Agrawal, who directs the Robotics and Rehabilitation Laboratory (ROAR) and Robotic Systems Engineering Laboratory (ROSE), located at both the Engineering School and Columbia University Medical Center.
While robotic exoskeletons have previously been the stuff of science fiction, research in Agrawal’s lab has helped advance the science to a point where robotic interfaces and exoskeletons are closer to real-world application. Cleverly designed to conform to the degrees-of-freedom within the skeleton of the human body, these devices are powered by motors that supplement the forces provided by the muscles and interact with the wearer—similar to the brain-controlled suit that helped a paralyzed Brazilian teenager kick a soccer ball at the World Cup opening ceremony.
“Neural disorders caused by stroke and spinal cord injury limit a person’s ability to do things we all take for granted: reach and raise our arms, walk, and perform activities of daily living. My research is aimed at helping these people accomplish everyday tasks.”
Perhaps some of the most fulfilling results from Agrawal’s research come when he sees how his work in robotics and movement has helped improve people’s ability to walk or use their arms again after a stroke or cerebral accident.
“I have seen stroke survivors learn to walk faster and with a more natural gait after several weeks of training with our robotic exoskeletons,” Agrawal says. “We have developed wire-driven arm and leg exoskeletons that can help train limb movements of adults neurally impaired by stroke. We have also designed robots that help infants and toddlers as young as six months learn to be mobile in their environment. I have seen how this technology changes lives.”
In addition to working on technology that improves patient outcomes, Agrawal receives funding from the National Science Foundation for novel design, trajectory planning, and control of intelligent machines like free-floating robots that can operate in the micro-gravity conditions of space, as well as for cable-actuated robotic platforms.
Agrawal’s robotic exoskeletons for arms, legs, torsos, and neck also help physical therapists provide frequent and intense therapy on patients to help build muscle memory, which can restore functionality.
“Robots can be similar to training wheels on a bicycle. They help the user gain proficiency in function until their support is no longer needed,” he says.
For infants and toddlers, Agrawal and his team have designed and tested novel mobility enhancement robots and control interfaces that have the ability to teach six-month-old infants seated on a mobile robot to purposefully drive using a joystick, and also to maneuver the robot in cluttered environments in their home using a force-feedback joystick. “This technology can help a child with limited mobility to interact with others and not be left far behind in achieving childhood milestones,” he explains.
Agrawal joined Columbia Engineering in 2013. Prior to that, he was a professor of mechanical engineering and director of the Mechanical Systems Laboratory and Rehabilitation Robotics Laboratory at the University of Delaware. His PhD advisor at Stanford University was Professor Bernard Roth who was the first PhD student under the guidance of Professor Ferdinand Freudenstein at Columbia University. Agrawal is an active contributor to the Institute of Electrical and Electronics Engineering and the American Society of Mechanical Engineers. He currently serves as chair of the ASME’s Design Division, which has more than 11,000 active ASME members.
Always on the lookout for novel approaches to solving problems, Agrawal is also targeting a new and growing population who will likely benefit from even more advanced robotic applications: seniors.
“As we age, our musculoskeletal and sensory systems decay, leading to a variety of health issues. This is getting to be a pressing challenge for our rapidly aging society,” he says. “We are currently developing and testing novel exercise and sensory interfaces for the elderly to enhance their balance and prevent fallrelated morbidities. Robotic technologies will be a substantial solution to keep our older population healthy and safe.”
—by Amy Biemiller