Inspired by the African primate galago, scientists at the University of California, Berkeley have designed a small robot that is the most vertically agile robot ever built. Named Salto (Saltatorial locomotion on terrain obstacles), the 10-inch tall robot can leap into the air and then spring off a wall, just like the African bush baby. It is also capable of performing multiple vertical jumps in a row.

Salto Jumping Robot
Image source: University of California Berkeley / YouTube video

It has the highest vertical-jumping agility for any robot

Duncan Haldane, the lead author of the study, believes that the one-legged robot could eventually help in search and rescue operations after earthquakes or building collapses. The robot can jump one meter in less than one second. Salto’s expertise lies in vertical-jumping agility, which is the ratio of the maximum jump height to the time taken to complete one jump.

Haldane says you need to “jump high and do it quickly” to have a high vertical-jumping agility. Salto can jump to a one-meter height in just 0.58 seconds and be ready to jump again. It gives the robot a vertical-jumping agility of 1.75 meters per second, the highest for any robot. That’s better than the bullfrog’s 1.71 meters per second, and the next best jumping robot Minitaur 1.1 m/s. Salto still lags behind the gravity-defying African galago’s 2.24 m/s.

Salto mimics galago’s crouched position

The African bush baby or galago is a small tree-dwelling, night-active primate. It is such an incredible leaper because the primate stores energy in its tendons when in a crouched position. The UC Berkeley scientists adapted it into Salto by using a spring-loaded, motorized leg mechanism that allows the robot to get into the same crouched position as the galago.

Salto doesn’t need to wind up before making a jump, thanks to power modulation. Duncan Haldane said his objective was to develop a search-and-rescue robot small enough not to disturb the rubble and jump quickly across different kinds of rubble. Salto weighs just 100 grams, and can achieve 78% of the galago’s vertical-jumping agility.

Salto not ready for real-world use yet

The one-legged prototype is still in lab experimentation stage. It’s not yet ready for real-world applications. Though researchers believe that it could be used in search and rescue operations in the future, the robot is not powerful enough to pull out someone trapped under a collapsed building. However, it may feature some sensors that could send signals to rescuers when it spots a trapped person.

Another issue with the robot is its battery life. The battery takes up 17% of its mass, but it is barely enough for the robot to function for a couple of minutes at a time. Published in the journal Science Robotics, the study was funded by the US Army Research Laboratory and the National Science Foundation.