Sunil Agrawal

Robotic exoskeletons that deliver superhuman strength or endurance are no longer just the stuff of science fiction, video games, or blockbuster movies. Instead, these intelligent machines are being developed to rehabilitate and assist people in accomplishing everyday tasks. By applying creativity and advanced engineering collaboration, scientists have developed exoskeletons to help patients with neurological disabilities improve their motor performance; help amputees regain dexterity and mobility; and deliver consistent, efficient, and enhanced physical therapy beyond the ability of human professionals.

One of the differences between the fantasy-inspired robotic suits portrayed in feature films like Iron Man and this technology is that these exoskeletons interact with, rather than encapsulate, their wearer.

“A majority of robotics research attempts to capture the capabilities of humans in machines,” explains Sunil Agrawal, professor of mechanical engineering at Columbia Engineering and pioneering researcher in intelligent machines. “On the contrary, my research in recent years has focused on how machines can help humans to improve their everyday functions. For example, a robot can be used to retrain a stroke victim to walk, or help a special-needs child to be safely mobile in a home environment.”

In the Robotics and Rehabilitation (ROAR) Laboratory, Agrawal directs research funded by the National Institutes of Health, which includes cable-driven leg exoskeletons and robot-enhanced mobility applications for children. The exoskeleton robotic applications, which are designed to be nimble extensions of the human body, are helping professionals deliver enhanced recovery and rehabilitative care, while making life easier and safer for those using the technology. This research not only improves quality of care and patient outcomes, but deeply resonates in Agrawal’s heart.

“I have seen stroke survivors learn to walk faster and with more natural gait after several weeks of training with our robotic exoskeletons,” says Agrawal. “We have developed wire-driven arm exoskeletons that can help train arm movements of neurally impaired adults with stroke, and mobile robots that help infants and toddlers as young as six months old learn to be mobile in their environment. I have seen how this technology changes lives.”

In addition to 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, and cable-actuated robotic platforms.

By applying the techniques of static and dynamic feedback linearization and differential flatness, Agrawal has pioneered novel approaches for design, trajectory planning, and optimization of robotic technology. His optimizations use a machine’s natural dynamics to enhance speed, efficiency, and robustness. Agrawal’s labs—the ROAR lab and the Robotic Systems Engineering (ROSE) Laboratory —engage an active group of PhD, MS, undergraduate, and post-doctoral researchers who apply these techniques to design robotic technologies that can be used in patient care or explore other novel applications of robotics.

Agrawal joined the Engineering School 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. He is an active contributor to the Institute of Electrical and Electronics Engineering, the International Committee on Rehabilitation Research, and the American Society of Mechanical Engineers where he serves on the executive committee of ASME Design Division and is slated to be its chair in 2014.

BS, Indian Institute of Technology, Kanpur, 1984; MS, Ohio State University, 1986; PhD, Stanford University in 1990.

by Amy Biemiller