Caltech has developed a new bionic robot called M4. It can autonomously assess the environment it faces and choose the most efficient combination of movements for navigation.
The new robot, called M4 (short for Multi-Mode Mobile Transformer), can reconfigure its body to achieve eight different types of movement. It rolls on 4 wheels, turns its wheels into rotors to fly, stands on 2 wheels and stares at obstacles like a meerkat, “walks” on wheels like legs, and uses 2 rotors. Can be used to roll on two wheels and roll down steep slopes.
Mollie Garib, PhD ’83, director of the Center for Autonomous Systems Technology (CAST) at Caltech, where the robot was developed, and the Hans W. Liebmann Professor of Aerospace and Bionic Engineering, said he said such a wide range of capabilities could have a wide range of applications, from transporting the wounded to hospitals to exploring other planets.
M4 is the brainchild of Ghalib and Alireza Ramezani, Assistant Professor of Electrical and Computer Engineering at Northeastern University. The team supporting the technical aspects of M4 includes Caltech Aerospace Postdoctoral Fellow Eric Siheit, CAST Design Engineer Reza Nemobi, and Caltech NASA administrator, Mr. Arash Karantari of the Jet Propulsion Laboratory. The paper announcing this new robot was published in Nature Communications on June 27, 2023.
This robot’s agile movement combined with artificial intelligence allows it to choose the most efficient form of movement based on the terrain ahead. If you imagine the M4 exploring unfamiliar environments, you may find yourself driving the most fuel-efficient four-wheeled vehicle available. When reaching a rocky obstacle, it can stand up on two wheels and see the ground ahead through the rocks. If there’s a canyon or terrain the wheeled robot can’t get through, the wheels can be converted into rotors that fly across the canyon to the other side and keep rolling.
One of the main features of the M4 is its reusable accessories such as wheels, legs and propellers. When the M4 needs two wheels to stand upright, two of the four wheels fold and the propellers rotate upward. When the M4 needs to fly, all four wheels fold and the propellers lift the robot off the ground.
The wheel assembly connector allows the M4 to perform walking motions. In the current iteration of the M4, walking is primarily a proof of concept. However, future developments may allow the M4 to effectively walk over rough terrain that wheeled robots have difficulty handling.
The design of the M4 is said to be heavily influenced by nature. For example, Galib and his colleagues have shown that quail (a species of quail) use wing flapping as leverage to push up steep slopes, while sea lions perform a variety of different maneuvers at sea and on land. I get tips on using my flippers while doing different types of sports. Biologists have been reporting examples of this type of appendage retrieval in the animal kingdom for some time, but the concept is now being explored in engineering.
The M4 has an autopilot feature that allows it to make its own decisions about how best to navigate complex environments. The robot has also been tested outdoors, navigating the terrain of the Caltech campus.
The Nature Communications paper is titled “Multimodal mobile morphobot (M4), a platform for examining appendage repurposing to enhance locomotor plasticity. The research was funded by the Jet Propulsion Laboratory and the National Science Foundation.