UC Berkeley student and faculty researchers presented their latest developments on the monopedal jumping robot “Salto” at the International Conference on Robotics and Automation, or ICRA, in Montreal, Canada, on May 21, according to a UC Berkeley press release.
According to the press release, Salto is a “Star Wars imperial walker in miniature” — student lead and electrical engineering doctoral candidate Justin Yim added that it stands just a foot tall when fully extended. Yim said Salto moves by “jumping around like a pogo” and can jump just less than four times its height in a single leap. Salto, which is an acronym for “saltatorial locomotion on terrain obstacles,” is the world’s most vertically agile robot, according to the press release.
“Small robots are really great for a lot of things, like running around in places where larger robots or humans can’t fit,” Yim said in the press release. “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.”
The research paper, which was chosen as a finalist for the ICRA Best Student Paper Award, according to ICRA’s website, suggests that legged robots could traverse environments impassable by other vehicles or robots that use wheels or tracks. Yim, who joined the project at its inception in 2015, said the objective of Salto was to mimic the mechanisms that animals use to jump in order to improve robotic performance. Yim added that the idea stemmed from the similarly small and agile animal, the bush baby.
According to Yim, he and his team used biomechanical research and have collaborated with the campus biology department. Bush babies uniquely use their muscles and tendons to store energy, which allows them to string together multiple jumps, according to the press release. Yim explained that the combination of the robot’s motor and spring similarly provides Salto with more power and allows it to jump to impressive heights.
During the conference, Yim and his team unveiled Salto’s newest capabilities.
“It was really exciting for me to present our robot and our work at (ICRA),” Yim said in an email. “Now that Salto runs outside of motion capture, I ran live demos at the conference that were really fun.”
According to Yim, the team’s most recent work has focused on getting Salto out of the lab and into new environments by developing onboard control and estimation algorithms. Because Salto’s movements are difficult to track, Yim’s team had previously used motion capture strategies with dozens of cameras to monitor the robot. Salto now only uses onboard gyroscopes and encoders, according to the research paper. Yim said this means that Salto can move autonomously or can be controlled by a human using a joystick controller.
As the research team further pursues Salto’s potential at Biomimetic Millisystems Lab, Yim said his team will continue to look toward the project’s principal investigator, electrical engineering and computer sciences professor Ronald Fearing.
“Salto is our first step toward robots that bounce around,” Fearing said in the press release. “It provides a basis for more complicated robots that also could be very highly dynamic.”