Two-part “stutter jumps” could reduce jumping robot power consumption
Researchers at the Georgia Tech School of Physics say they have developed a novel jumping strategy for hopping robots that reduces power consumption. Associate Professor Daniel Goldman and Graduate Student Jeffrey Aguilar analyzed almost 20,000 jumps made by a simple robot designed to test jumping dynamics and discovered that a so-called "stutter jump" – where a robot builds up momentum by first making smaller hops before a big jump – requires a tenth of the power normally expended when performing the bigger jump from scratch.
“The preparatory hop allows the robot to time things such that it can use a lower power to get to the same jump height,” Goldman said. “You really don’t have to move the mass rapidly to get a good jump.” The test rig was comprised of a rod with a spring at the end, much like a pogo stick, that moved up and down. A computer controlled the rod, while a high-speed camera and contact sensors measured and recorded the height and position of each jump.
The research suggests that there is still room for further exploration of jumping robots, a form of locomotion that has largely fallen out of favor among roboticists. Back in the 1980s, Boston Dynamics' founder Marc Raibert worked on hopping robots that used similar pogo stick-like appendages at MIT's Legged Robotics Lab, but today the vast majority of projects opt for wheels or legs with multiple joints. However, given the large number of animal species that jump, it's possible that future generations of biomimetic robots, like those based on insects, will do the same.
Goldman and his team will also explore how different surfaces, such as sand, affect jumping. They hope that their research will allow future robots – such as those designed for military or search and rescue operations like the hopping robots developed at Sandia Labs – to jump successfully regardless of conditions.