South Korea’s Korea Institute of Machinery and Materials (KIMM) is pioneering a new “morphing” wheel that could revolutionize mobility for people and robotics. Imagine a wheelchair equipped with wheels flexible enough to handle obstacles like curbs, humps, and even staircases. Or envision an unmanned delivery vehicle taking the stairs to deliver food and groceries to your doorstep. This is the vision for the morphing wheel, capable of overcoming obstacles up to 1.3 times the height of its radius.
Inspired by the surface tension of water droplets, this innovative wheel changes its form from solid to fluid as it encounters obstructions, adapting dynamically to its environment. The morphing wheel could also benefit robotics in challenging terrains, including surveillance or combat robots on the battlefield, where maneuverability is crucial. Additionally, KIMM hopes to use morphing wheels on two- and four-legged robots, improving stability and payload management in industrial settings where smooth movement is essential.
Principal researcher Song Sung-hyuk at KIMM explains that unlike other wheels, such as non-pneumatic or airless tires, the morphing wheel’s flexibility is enhanced with obstacle-handling capabilities. Built with an outer hoop of chain links and spoke wires extending through the hub, the wheel’s stiffness is automatically adjusted by sensors based on the terrain. In a recent demonstration, a prototype wheelchair with morphing wheels successfully climbed stairs with 18-cm steps while carrying a life-sized dummy.
The morphing wheel can currently reach speeds up to 30 kph, with hopes of making it viable at car speeds, or up to 100 kph. This breakthrough was highlighted in the August issue of Science Robotics, showcasing the wheel’s potential to transform mobility across various fields, from personal aids to advanced robotics.