Researchers at Texas A&M have designed a compact four-wheeled robot for whom stairs and other uneven terrain pose no problems — thanks to wheels which can transform themselves into "legs" on demand.
Dubbed α-WaLTR, for the Adaptable Wheel-and-Leg Transformable Robot, the robot has been built as part of DARPA's Offensive Swarm-Enabled Tactics (OFFSET) programme under the leadership of grant awardee Associate Professor Kiju Lee. "Through this new project," Lee explains, "I will develop unmanned ground vehicles with agile and versatile locomotive capabilities for urban military operations.
"Legged locomotion is more versatile, but suffers from inherent structural, mechanical and control complexities. The proposed testbed will be equipped with novel wheel/leg transformable mechanisms, which can switch between the two locomotion modes actively adapting to its environment, but without needing any additional actuator."
On even terrain, α-WaLTR works like any other four-wheeled robot: Its wheels turn to provide locomotion and turning capabilities. During transformation mode, however, the wheels open out into three-bladed "legs" which allow it to traverse uneven terrain — even travelling up and down stairs without difficulty, the researchers hope. The decision to switch between modes, meanwhile, is entire local: The robot decides for itself the best method of locomotion.
More details on the project are available on the Texas A&M Engineering website; the first hardware prototype is expected to be showcased at the OFFSET FX5 event in February 2021.