This is the airless wheel I used for Electropositive. Let's start with a Michelin Tweel (I have never tested them, but they seem to be great thing) and add some design tweaking.
The entire structure is a single piece made out of alternate facing tetrahedra whose edges form the general shape of the spokes and ribs (visible inside the wheel) elements. By using the triangle as the basic structure of all the elements, very high strength can be acquired without sacrificing the weight. Instead of using steel wire as reinforcement for the rubber, it is used Kevlar for its high tensile strength.
The Threel acts as a combination of bike and car wheel, the lateral and top supporting tension forces which are handled by the Kevlar reinforcement and the area under the hub (motor in this case) supporting compression forces handled by the rubber.