Two-Legged Robot Developed with Running Ability

MABEL robot (University of Michigan)

Engineers at University of Michigan in Ann Arbor have developed a bipedal robot with the ability to run as well as walk. MABEL, as the robot is called, is funded by the National Science Foundation and Defense Advanced Research Projects Agency.

MABEL was first developed in 2008 as a collaboration between Michigan’s Jessy Grizzle, a professor in the Department of Electrical Engineering and Computer Science, and Jonathan Hurst, then a doctoral student at Carnegie Mellon University, and now at Oregon State University. Current grad students in Grizzle’s lab have since enhanced MABEL’s feedback algorithms that make it possible for the robot to run, which requires keeping its balance while reacting to its environment in real time.

The research team says MABEL is unique in that it has a human-like gait, with weight distributed over its structure like a human body. The robot has, for example, a heavier torso and light, flexible legs with springs that act like tendons. Grizzle says MABEL, when running, is airborne for 40 percent of each stride, much like human runners. Other robots leave the ground for no more than 10 percent of their strides, which resembles speed-walking more than running.

Many robots achieve mobility on wheels, rather than emulating human walking or running. Koushil Sreenath, one of Grizzle’s doctoral students working on MABEL, notes that wheels are fine to move across flat surfaces, but when the ground gets rocky, two legs are more efficient.

Two-legged robots with good running form, say the researchers, could one-day serve as robotic soldiers or rescuers, being able to travel over rough terrain and inside places built for humans. Research on running robots could also lead to more sophisticated prosthetic devices or exoskeletons that can behave like their biological counterparts.

*     *     *