MARLO Bipedal Robot Walks Over Snow And Rough Terrain With Ease

Researchers from the University of Michigan have been working on a freestanding bipedal robot called MARLO. Electrical engineering professor Jessy Grizzle and his students have been working on MARLO in an attempt to get the unsupported robot to be able to walk across varied terrain without issue. The team believes that the feedback control used in the robot could be used in other devices like powered prosthetic legs in the future.

"The robot has no feeling in her tiny feet, but she senses the angles of her joints—for instance, her knee angles, hip angles and the rotation angle of her torso," said Jessy Grizzle, professor of electrical engineering and computer science and of mechanical engineering. "It's like walking blindfolded and on stilts."

MARRLO is the first robot that the team has worked with that can walk and fall in any direction, a feat known as 3D walking. The team previously worked with a less complex robot called MABEL that could move in two dimensions and was attached to a boom to give sideways stability. The team of researchers developed a way to control the robot with 2D algorithms, something that could help speed the process of achieving stable walking with other robots used in research.

There is a main controller that handles forward and backward motion and balance with a second controller that handles side-to-side balance. Doctoral student Xingye Da created a library of 15 gaits to handle different walking speeds and ground heights. Each of those gaits is optimized for energy efficiency. MARLO is able to step blindly and adjust gait to terrain and speed by fitting one of the gaits from the library to the environment. An Xbox controller is used to tell the robot what direction to walk and how quickly to walk, choosing the correct gait is up to the robot.

SOURCE: University of Michigan