Instantiations of the Dream:

• n is the number of front wheels
• t is the number of tilting wheels
• unless otherwise noted, each is rear-wheel drive.

For tilting types, I use this notation, as proposed by J. Bond and adhered to on this site:

• Natural. Bikes, passive 3 wheel mechanisms. There are no systems to change the lean angle. Any change happens purely through weight transfer and steering movements. The machine is always in balance or it falls over.
• Assisted. The rider has a control that directly affects the lean angle in addition to simple weight transfer and steering. The rider has to maintain balance.
• Active. The machine decides the lean angle. The rider has no direct control. The machine maintains balance even if it was moving with no rider.

With further thanks to Mitch Casto and Larry Edwards, I use this notation for motive power:

• Gas. Two- or four-stoke internal combustion engine.
• Electric. Batteries and a motor or motors, AC or DC.
• Hybrid. Either serial (the internal combustion engine can only charge the batteries) or parallel (the internal combustion engine both charges the battery pack, but can also be engaged to provide drive torque on demand or when the batteries weaken).

Another tip' o the bomber's cap to Mitch Casto and Larry Edwards, I use this notation for seating:

• 1 seat. Just the driver.
• 2 seats. Driver and passenger sitting side-by-side.
• 1+1 seats. Driver and passenger, with one seat behind the other.

A last flap o' the silk scarf to Mitch Casto and Larry Edwards, I use this notation for cabin configuration:

• Open. Like a motorcycle or scooter, no roof, no roll cage.
• Closed. Covered or canopied with a permanent roof.
• Semi-open. Roll cage or convertible roof, fabric or rigid.

There are five parts to this site:

• Motorized Prototypes
• Human Powered Prototypes
• Designs and Simulations
• Patents
• TTW Links, Articles, and Related Points of Interest

And a note on intellectual property and copyright: as far as I know, everything on this page is available elsewhere on the web, and all sources are cited. Complaints and questions are always elcouraged, email me.