May 29 2019
Scientists at the University of California, Berkeley (UC Berkeley) have created a new, agile robot, known as Salto, as part of a research project for the U.S. Army.
Resembling a Star Wars Imperial walker in a compact size, the robot may prove useful in search-and-rescue and scouting operations. According to the researchers, such robots could be used to save the lives of both civilians and warfighters in the future.
Standing at less than a foot, the Salto—short for saltatorial (jumping like a grasshopper) locomotion on terrain obstacles—now includes an advanced control systems that enables it to perform increasingly difficult tasks, for example, navigating an obstacle course, bouncing in place, or tailing a moving target, all regulated with a radio controller.
In the year 2016, the researchers showed how the Salto robot can take a leap and then instantly jump higher by bouncing off a wall. This makes Salto the most vertically agile robot in the world—leaping over three times its height.
With its latest capabilities, Salto is believed to spur the advancement of tiny, agile robots that can possibly jump through the rubble to help in several military missions, including search-and-rescue operation.
The physical environment the Army operates in is highly irregular, cluttered, and constantly changing. The science underlying the advancements is critical for achieving the desired mobility, speed of action, and situational awareness generation necessary for future Army operations.
Dr Samuel Stanton, Program Manager, Army Research Office
Army Research Office is a part of U.S. Army Combat Capability Development Command’s Army Research Laboratory.
The researchers described the latest capabilities of the robot at the 2019 International Conference on Robotics and Automation, held in Montreal on May 21st, 2019.
Small robots are really great for a lot of things, like running around in places where larger robots or humans can’t fit. For example, in a disaster scenario, where people might be trapped under rubble, robots might be really useful at finding the people in a way that is not dangerous to rescuers and might even be faster than rescuers could have done unaided. We wanted Salto to not only be small, but also able to jump really high and really quickly so that it could navigate these difficult places.
Justin Yim, Robotics Graduate Student, University of California, Berkeley
Yim works with electrical engineering and computer sciences professor Ronald Fearing at UC Berkeley, whose Biomimetic Millisystems Lab studies the mechanics of animal movement and how they can be leveraged for developing more nimble robots.
Fearing’s laboratory is popular for constructing robots that are inspired by insects and are capable of safely crawling across difficult surfaces that are too rough or too smooth to be navigated by a wheeled robot.
The single, powerful leg of the Salto robot is designed after those of the galago, or Senegalese bush baby. Tendons and muscles of a tiny, tree-dwelling primate can retain energy in a way that gives the agile animal the potential to string together various jumps in just a matter of seconds.
By connecting a sequence of rapid leaps, the Salto robot can also navigate difficult terrains—for example, a pile of debris—that may not be possible to cross without flying or jumping.
Unlike a grasshopper or cricket that winds up and gives one jump, we're looking at a mechanism where it can jump, jump, jump, jump. This allows our robot to jump from location to location, which then gives it the ability to temporarily land on surfaces that we might not be able to perch on.
Ronald Fearing, Professor, Department of Electrical Engineering and Computer Sciences, University of California, Berkeley
In addition, Yim has fitted the Salto robot with a novel technology that enables it to feel its own body, telling it the bend of its leg and what angle it is pointing.
The Salto robot, without these abilities, has been placed in a room in one of the engineering buildings at UC Berkeley. Here, motion capture cameras monitor the precise position and angle of Salto and transfer that data back to a PC, which quickly crunches the numbers to tell the robot how to angle itself for its subsequent leap.
Now that the robot has a sense of itself and its own motion, it can perform these computations for itself, enabling Yim to take it outside and utilize a radio controller and joystick to instruct it where to go.
By understanding the way that these dynamics work for Salto, with its mass and size, then we can extend the same type of understanding to other systems, and we could build other robots that are bigger or smaller or differently shaped or weighted.
Justin Yim, Robotics Graduate Student, University of California, Berkeley
In the days to come, Fearing hopes to study the possibilities for hopping robots.
This Army investment extends the current state of the art for small ground robot mobility beyond what is currently capable through traditional wheeled and tracked locomotion which are severely limited in complex three-dimensional terrain. These advances will inform and guide our Army Research Laboratory researchers as they continue to develop innovative solutions for robotic actuation and mobility and will enable agile robots that can go anywhere a Soldier can and beyond. This research brings us a step closer to providing our warfighters with effective unmanned systems that can be deployed in the field.
Dr Brett Piekarski, Vehicle Technology Directorate, Army Research Laboratory
SALTO - Teaching an old robot new tricks
Video credit: U.S. Army Research Laboratory