By Hyun Young Yi, Daewoung Kim and Jack Kim
DAEJEON, South Korea (Reuters) – Imagine a wheelchair equipped with wheels flexible enough to overcome all kinds of obstacles, from curbs to bumps and even stairs.
Or perhaps an unmanned delivery vehicle that uses the same wheels as the stairs to deliver food and groceries to your door.
This is what researchers at the Korea Institute of Machinery and Materials (KIMM) envision with their “morphing” wheel, which can roll over obstacles up to 1.3 times the height of its radius.
Inspired by the surface tension of water droplets, it goes from solid to liquid when it encounters obstacles.
Other possible applications include robots that spy on the enemy on the battlefield.
The KIMM team also hopes that morphing wheels will eventually be used in two- and four-legged robots, which are currently limited in movement efficiency and sensitive to vibration, that can transport loads that require stable movements in industrial environments.
“The goal is to make this feasible for speeds up to 100 km per hour, or the speed of an average car,” said Song Sung-hyuk, lead researcher at South Korea’s KIMM.
Wheels developed for a similar purpose, such as non-pneumatic or airless tires, have flexibility but are limited in their ability to overcome obstacles, said Song, a member of KIMM’s AI robotics research team.
The morphing wheel consists of an outer ring of chain and a series of spoke wires running through the hub. The stiffness of the spokes – and therefore of the wheel – is automatically controlled by a sensor as it responds to the terrain.
Song’s team demonstrated to Reuters a prototype wheelchair mounted on morphing wheels as it climbed a staircase with 7-inch steps containing a life-size dummy. The team also tested a device mounted on the handlebars at speeds of up to 30 km/h.
The morphing wheel was the cover story of Science Robotics magazine in August.
(Reporting by Hyun Young Yi, Daewoung Kim and Jack Kim; Editing by Nicholas Yong)
