How to fall gracefully if you're a robot

October 14, 2015 by Tara La Bouff, Georgia Institute of Technology
How to fall gracefully if you’re a robot
Robot braces its fall based on new algorithm.

Miss Georgia tripped in the final round. Jennifer Lawrence stumbled on her way to accept an Oscar. Even rock stars, world leaders and presidential candidates have fallen in front of the crowd or completely off stage.

And robots can too.

Researchers at Georgia Tech have identified a way to teach robots how to fall with grace and without serious damage. The work is important as costly robots become more common in manufacturing alongside humans. The skill becomes especially important, too, as robots are sought for health care or domestic tasks – working near the elderly, injured, children or pets.

Ph.D. graduate Sehoon Ha and Professor Karen Liu developed a new algorithm that tells a how to react to a wide variety of – from a single step to recover from a gentle nudge, to a rolling motion that breaks a high-speed fall. As a result, robots can minimize the damage or injury they might cause to themselves or others while falling by learning the best sequence of movements to slow their momentum. The planning algorithm was validated in physics simulation and experimentally tested on a BioloidGP humanoid.

"A fall can potentially cause detrimental damage to the robot and enormous cost to repair," said Ha, who graduated in summer 2015 and is now a postdoctoral associate at Disney Research Pittsburgh in Pennsylvania. "We believe robots can learn how to fall safely. Our work unified existing research about how to teach robots to fall by giving them a tool to automatically determine the total number of contacts (how many hands shoved it, for example), the order of contacts, and the position and timing of those contacts. All of that impacts the potential of a fall and changes the robot's response."

With the latest finding, Ha builds upon Liu's previous research that studied how cats modify their bodies in the midst of a fall. Liu knew from that work that one of the most important factors in a fall is the angle of the landing. She also knew that a well-designed robot has the "brain" to compute a softer landing, but hadn't yet optimized the sequence of motions that take place during a fall, like she and Ha were able to do in their latest research.

"From previous work, we knew a robot had the computational know-how to achieve a softer landing, but it didn't have the hardware to move quickly enough like a cat," Liu said. "Our new planning algorithm takes into account the hardware constraints and the capabilities of the robot, and suggests a sequence of contacts so the robot gradually can slow itself down."

Now the robots may fall more gracefully than people and possibly cats, too. Imagine that.

The research, entitled "Multiple Contact Planning for Minimizing Damage of Humanoid Falls," was presented this month at the IEEE/RSJ International Conference on Intelligent Robots and Systems in Hamburg, Germany.

In the video, the top robot uses a novel algorithm to minimize impact when the robot falls. The algorithm is not used for the robot on the bottom of the screen.

Explore further: Cats and athletes teach robots to fall

Related Stories

Cats and athletes teach robots to fall

November 13, 2014

A cat always lands on its feet. At least, that's how the adage goes. Karen Liu hopes that in the future, this will be true of robots as well.

Video: Can robots make good teammates?

September 22, 2015

Are they our evil overlords, or our personal servants? Another possibility altogether is that they're our dependable co-workers, helping us put together that new Ikea bookcase.

Dutch people not in favour of humanoid robots

July 8, 2015

Most Dutch people feel that the ideal social robot should not resemble a human being too much, as is the case with robots currently being produced in Japan. People do expect a robot to have certain human traits, but the distinction ...

Evolving robot brains

March 2, 2015

Researchers are using the principles of Darwinian evolution to develop robot brains that can navigate mazes, identify and catch falling objects, and work as a group to determine in which order they should exit and re-enter ...

Recommended for you

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.