Robots to Flex New-found Muscles 

The thought of robots interacting with humans is no longer a blurry vision of the future. While the lighthearted portrayal of R2D2 or Wall-E are still a far cry from what we see with industrial robots, the trend shows an important shift in public perception. Still, small, fragile, and friendly robots such as could take a turn towards scary as they begin to pack on pounds of robotic muscle.

This idea may be concerning to some, but the fact remains that increased strength is a necessary feature of many robots. And the results of added muscle can be staggering. For example, the BigDog robot from Boston Dynamics can throw cinder blocks and the RoboSimian from the NASA Jet Propulsion Laboratory can swing on its arms like a gymnast. While this strength is impressive for a robot, this is by no means the limit.

Robots like the BigDog and RoboSimian move with the help of hydraulics. This system, based on pressurized fluid, makes their movements slow and jerky. Not only that, it restricts the potential of their strength, allowing them to only lift half of their own weight—about the same as a human.

For roboticists, this isn't good enough. As such, engineers at the National University of Singapore have developed a stretchy plastic that could be used with robots to serve as artificial muscle. Pulses of electricity would control the muscle, allowing it to react just as quickly as a human’s.

This is not the first time plastic muscles controlled by electrical pulses have been used for robotics. However, the work by the Singapore team may prove the strongest system to date. 

“Last year, we calculated theoretically that polymer muscles driven by electrical impulse could potentially have a strain displacement of 1,000 percent, lifting a load of up to 500 times its own weight. So I asked my students to strive towards this Holy Grail, no matter how impossible it sounded,” said Adrian Koh, research lead. 

Thus far the team has created muscle that allows a robot to bear 80 times its own weight and stretch to five times its original length. They believe that the muscle could eventually be stretched to ten times its original length.

Right now the team is working on a robotic arm that will be strong enough to defeat a human in arm wrestling despite being half the size and weight of a human arm. They expect to have it completed in three to five years and are in the process of filing a patent for both the plastic and the pulse system.