Prototypes:
The value of prototyping is a fundamental credo at the Stanford program and I lived by it on this project. To quote Tom Kelley of IDEO in his book "The Art of Innovation": "Prototyping is problem solving. It's a culture and a language. You can prototype just about anything. . . what counts is moving the ball forward. . . ."
I began with a little radio-controlled prototype of the idea. The R/C models used purchased "omni-wheels" used in conveyor belt systems and cannibalized, cheap model cars. The outer hexagonal frame of each cart spun on a lazy-susan bearing. Magnets along one edge in each frame would let the carts link up. The free-spinning frame and the omni-wheels coupled to create a cool composite motion.
Small scale, big laughs.
A few test-driving sessions by some fellow students full of raucous screaming and shouting were enough to convince me the idea had merit.
Radio controlled sumo wrestling.
My first full-size prototype was simply a scaled-up version of the radio-controlled carts. I used hard plastic swimming lane buoys to recreate the omni-wheel effect. The curvature of the buoys defined the major diameter of the wheel and each buoy could spin on its own axle. Thus, at any instant you could be rolling forward or backward, and sliding left or right. This prototype kindof worked but it was very large, heavy and it self destructed after a few test sessions.
The first full-scale omni-cart.
I went back to the omni-directional drawing board and proceeded to make a whole slew of track-ball-inspired prototypes. These were all much better at pinching your fingers than at moving you around.
One of the ill-fated track ball experiments.
I decided to revisit the omni-wheel concept and ended up making the prototype you see at right. A solid polycarbonate axle is bent around the circumference of a wheel, creating an axle for 32 roller-blade wheels. This prototype was light, maneuverable, and created the most amazing driving-on-ice feeling. I made a second one and started battling . . . I mean cooperating . . . with the faculty.
The final prototype.