The EngineerOnline has a couple of interesting posts on new mobility devices; a super scooter and a morphing handcycle...so lets begin with the handcycle.
In a stretched-out low-rider position, it’s a traditional bicycle - but when "morphed" into high-rider position, it has a wheelchair’s agility for navigating doorways and aisles. It also puts the user at eye level with standing persons.
The morphing handcycle involves no electronics. To morph into high-riding position, the rider sets the brake and rolls the rear wheels forward, as with a wheelchair. The 24-speed cycle employs twin mechanical gas shocks, specified for the rider’s weight, that assist in the lift, enabling the user to switch to high-riding mode with single-hand force. Other components are standard bike parts.
ii) the super scooter:
Prof William J. Mitchell and several of his students at MIT have developed a new electric scooter that folds up when not in use....Motor scooters are a very popular form of transportation in Asian and European cities, Mitchell said, because they provide convenient, inexpensive transportation. But conventional scooters, using inefficient two-stroke petrol engines, are also a source of local air pollution.
The non-polluting electric design, which eliminates the powertrain by putting motors directly inside each of the two wheels, made it possible to design the scooter so that it could be folded up to about half its size, making it easy to store in crowded urban environments.