Physicists Build a Wheel that Rolls Uphill

University of Amsterdam’s Corentin Coulais and University of Chicago’s Vincenzo Vitelli, along with their collaborators, invented a wheel that seemingly defies physics. Dubbed “Odd Matter,” the wheel—comprised of six small motors tethered together with plastic arms and rubber bands—wiggles and gyrates to travel uphill. This writhing enables the wheel to adjust to difficult terrain despite not having any cognizance of the environment. It’s a phenomenon founded on “odd elasticity,” a property that describes how a material, once stretched or squashed in one direction, does not engender a reciprocal reaction in the other. As such, when the material undoes a deformation, it contains excess energy, allowing it to travel uphill. Scientists coupled this property with robotics, outfitting a chain of modules with a motor, sensor and microcontroller, so that each module would not respond reciprocally. This thought process combines physics and robotics to generate collective behavior in robots that are crafted from simple parts obeying simple laws. Odd Matter is just one of the latest innovations from this “Robophysics” space. Learn more at Wired.

Image courtesy of Corentin Coulais