By Julie Baumkel
For scientists at The Massachusetts Institute of Technology, the future may look a lot like the denizens of nature — specifically, a bounding, leaping, running robot that mimics the characteristics of Earth’s fastest land animal, the cheetah.
According to MIT scientists, these bio-inspired characteristics may be essential if humans want robots in the future to help them carry loads, or explore places that are too dangerous for people, such as nuclear disaster sites.
How it works
The MIT team’s robotic cheetah creation is a great improvement over most robots, which are sluggish and heavy and cannot control force in a high-speed situation. The latest version of MIT’s robotic creation couples specially designed robot legs with a custom, high-torque density electric motor to allow it to run by itself on uneven grassy terrain at up to 10 miles per hour.
Like a hopping rabbit, the MIT robot bounds, with both forefeet touching the ground first and pushing off. Then, the hind feet hit the ground at once and continue the momentum. One MIT scientist involved with the project compares the robot to a human sprinter.
“Many sprinters, like [Jamaican sprinter] Usain Bolt, don’t cycle their legs really fast,” says Sangbae Kim, an associate professor of mechanical engineering at MIT involved with the project. “They actually increase their stride length by pushing downward harder and increasing their ground force, so they can fly while keeping the same frequency.”
MIT Biomimetic Robotics Laboratory members, including Sangbae Kim and his colleagues — research scientist Hae won Park and graduate student Meng Yee Chuah — unveiled their leaping, bounding creation to the public in the fall.
A new perspective
Kim says biology can provide new perspective for scientists. “But we can’t just copy nature,” he recently said in a lecture to college students. “In order to learn effectively, we need to find a common principle.”
The principle behind the movement of the cheetah robot grew out of a long process of bio-inspired design originating 10 years ago with Kim’s study of the running movements of a cockroach. He developed what he calls the “slip” model for running or spring-loaded pendulum model.
As these bio-inspired design processes have evolved, so have the robots created by the MIT team. For example, in 2012, like the real-life cheetah as he stalks his prey, the cheetah robot gained a tail to effectively stabilize the body after a disturbance.
It’s all in the math
Also, compared to galloping robots developed in other labs, bounding is easier to model mathematically, Kim notes. That’s why the MIT cheetah robot’s newest algorithm controls the amount of force the robot’s feet exert when they push off the ground.
The MIT team presented the algorithmic details of the bounding cheetah in September at the IEEE/RSJ International Conference on Intelligent Robots and Systems in Chicago.
We’ll wager the late, great science fiction author Isaac Asimov, known for a robot series that launched with “I, Robot,” is likely cheering from above.