An agile jumping robot that was inspired by some of the world’s best leapers in the animal kingdom could one day help in rescue efforts after earthquakes or building collapses, US scientists said Tuesday (Dec 6).

Known as Salto, the 10-inch (26-centimetre) tall Robot can jump higher than a bullfrog and almost as high as a galago, or bush baby, a small primate found in Africa. The robot can jump one meter in less than one second, according to the report in the journal Science Robotics.

That’s better than a human but not the highest of any robot – other machines that have been made can jump more than three meters in a single leap.

Record Vertical Jumping Ability

Salto does hold the crown in vertical-jumping agility, which researchers define as the ratio of the maximum jump height to the time it takes to complete one jump.

“To have a high vertical-jumping agility, you have to be able to jump high and do it quickly,” explained Duncan Haldane, a researcher at the University of California, Berkeley, and lead author of the study.

According to co-author Justin Yin, “Salto can jump to a height of one meter in 0.58 seconds and be immediately ready to jump again.” This means Salto can achieve a vertical-jumping agility of 1.75 meters per second, the highest such ratio of any robot to date. Salto, for saltatorial locomotion on terrain obstacles, achieved 78 percent of the vertical jumping agility of a galago, the animal kingdom’s most vertically agile creature. Salto, which stands for “saltatorial locomotion on terrain obstacles,” weighs just 100 grams.

How this tiny robot jumps so quickly

“The special thing we built into this robot is they can get really, really low into a crouch and have more time to stretch out their tendons, and then store energy that way and release it”, Haldane said. Vertical agility combines the size of a single bound with the frequency at which the jump can be executed in succession. The researchers adapted that into Salto by using a motorized, spring-loaded leg mechanism that lets the robot get into the same type of crouched position. By using power modulation, Salto doesn’t need to wind up before a jump; as soon as it jumps, Salto is ready to jump again. Like the galago, Salto can jump both high and fast.

Salto can use the wall to jump higher. “We’re particularly interested these days in seeing if we cannot just match but exceed the performance of animals”, said UC-Berkeley electrical engineering and computer sciences professor Ronald Fearing, who heads the lab where Salto was developed. Despite being just over 10 inches tall when fully extended, Salto can jump from a stationary position to a height of one meter (39 inches).

Watch it in action:

This jumping robot is a ninja

The one-legged robot can jump from the floor, flip forward and then kick off a wall, reaching even greater heights. Researchers hope it will aid rescuers by offering a robot that can easily navigate rubble and tough terrain.

“What originally inspired us to do this work was speaking with first responders down at the Federal Emergency Management Agency (FEMA) Urban Search and Rescue Training site in Menlo Park, California, where they have these giant rubble piles simulating collapsed buildings,” Haldane told reporters on a conference call.

“Our goal was to have a search-and-rescue robot small enough to not disturb the rubble further, and to move quickly across the many kinds of rubble produced by collapsed buildings.”

Aiding in earthquake aftermath

The robot would not be powerful enough to pull a person out of a collapsed building, but might be equipped with sensors that could tip off rescuers to the location of a trapped person. The single-legged prototype was developed for lab experimentation and is not ready for real-world use. Battery life is also a problem. The battery takes up 17 per cent of the robot’s mass, and allows it to function for only a couple of minutes at a time.

“Depending on the task that you want to accomplish, you’re going to trade off battery life for how high you can jump,” said Haldane. The study was funded by the US Army Research Laboratory and the National Science Foundation, which is interested in building robots that can maneuver through challenging terrain.