When it comes to navigating difficult terrain, four-legged robots such as Boston Dynamics’ Spot are king, as the legs provide a stable center of gravity, even on rocky slopes. Transition over to flat surfaces and those four-legged robots become inefficient compared to those outfitted with wheels. Engineers at ETH Zurich’s Robotic Systems Lab have designed a robot that utilizes both legs and wheels, giving it a dynamic hybrid walking/driving ability that can handle any terrain.
Known as ANYmal, the quadruped robot is outfitted with actuated wheels that the engineers state “might be a solution for any real-world application requiring rapid, and long-distance mobility skills on challenging terrain.” ANYmal was created using torque-controllable actuators, which provides the legs enough power to traverse stairs and other obstacles. The wheels are torque-driven as well, and are non-steerable, meaning they can’t turn left or right, which allows the robot to remain stable when transitioning different terrain.
ANYmal is outfitted with LIDAR, GPS, wide-angle, and depth cameras, allowing it to map its environment and position itself in the assigned area. The robot processes the sensor data using an onboard computer outfitted with a pair of Intel i7 hexa-core processors, and then uses the data to plan its navigation path, and what type of locomotion to use to safely traverse the area.
The engineers tested their ANYmal robot at DARPA’s Subterranean Challenge, which the research agency states, “robots compete to rapidly map, navigate, search, and exploit complex underground environments, including human-made tunnel systems, urban underground, and natural cave networks.” With that in mind, the engineers hope to use the robot for search and rescue operations in hazardous areas, but the platform is still in the development stage to improve its wheel grip and other hardware before its deployed.