Michelin has developed a new non-pneumatic car wheel that has been adopted for various robotics uses. It reminds me of the "Smartwheels" in Neal Stephenson's Snow Crash: "Each one consists of a hub with many stout spokes. Each spoke telescopes in five sections. On the end is a squat foot, rubber tread on the bottom, swiveling on a ball joint. As the wheels roll, the feet plant themselves one at a time, almost glomming into one continuous tire. If you surf over a bump, the spokes retract to pass over it. If you surf over a chuckhole, the robo-prongs plumb its asphalty depths."
The heart of Tweel innovation is its deceptively simple looking hub and spoke design that replaces the need for air pressure while delivering performance previously only available from pneumatic tires.
The flexible spokes are fused with a flexible wheel that deforms to absorb shock and rebound with ease. Without the air needed by conventional tires, Tweel still delivers pneumatic-like performance in weight-carrying capacity, ride comfort, and the ability to "envelope" road hazards.
Michelin has also found that it can tune Tweel performances independently of each other, which is a significant change from conventional tires. This means that vertical stiffness (which primarily affects ride comfort) and lateral stiffness (which affects handling and cornering) can both be optimised, pushing the performance envelope in these applications and enabling new performances not possible for current inflated tires.