Cockroaches and lizards were the inspiration for a new high-speed amphibious robot developed at Ben-Gurion University of the Negev (BGU). The robot can swim, run on top of water and crawl on difficult terrain.

Bioinspired and Medical Robotics Laboratory Director David Zarrouk and graduate student Avi Cohen presented the mechanical design of the AmphiSTAR robot and its control system at the virtual IROS (International Conference on Intelligent Robots and Systems) that continues this month.

“The AmphiSTAR uses a sprawling mechanism inspired by cockroaches, and it is designed to run on water at high speeds like the basilisk lizard,” says Zarrouk. “We envision that AmphiSTAR can be used for agricultural, search and rescue and excavation applications, where both crawling and swimming are required.”

AmphiSTARis a wheeled robot fitted with propellers whose axes can be tilted using the sprawl mechanism. The propellers can serve as wheels or fins at high speeds of 1.5 meters per second (m/s) depending on the terrain.

Air tanks allow the robot to float and transition between high speeds when hovering on water to lower speeds when swimming, and from crawling to swimming and vice versa.

The experimental robot can attain speeds of 3.6 m/s (3.3 mph) just like the original STAR robot while crawling over gravel, grass and concrete.

Zarrouk has been developing robots for many years, including other STAR robots.

His minimally actuated serial “snake” robot uses only two motors to maintain its lightweight and function. In 2019, Zarouk’s group unveiled the FSTAR robot drone that not only flies, but also travels over rough terrain.

“Our future research will focus on the scalability of the robot and on underwater swimming,” Zarrouk says.

Zarrouk’s research was supported in part by the BGU Helmsley Charitable Trust through the Agricultural, Biological and Cognitive Robotics Initiative, and by the Marcus Endowment Fund, both at BGU.