Cars are immensely complicated machines, but when you get down to it, they do an incredibly simple job. Most of the complex stuff in a car is dedicated to turning wheels, which grip the road to pull the car body and passengers along. The steering system tilts the wheels side to side to turn the car, and brake and acceleration systems control the speed of the wheels.
Given that the overall function of a car is so basic (it just needs to provide rotary motion to wheels), it seems a little strange that almost all cars have the same collection of complex devices crammed under the hood and the same general mass of mechanical and hydraulic linkages running throughout. Why do cars necessarily need a steering column, brake and acceleration pedals, a combustion engine, a catalytic converter and the rest of it?
According to many leading automotive engineers, they don't; and more to the point, in the near future, they won't. Most likely, a lot of us will be driving radically different cars within 20 years. And the difference won't just be under the hood -- owning and driving cars will change significantly, too.
In this article, we'll look at one interesting vision of the future, General Motor's remarkable concept car, the Hy-wire. GM may never actually sell the Hy-wire to the public, but it is certainly a good illustration of various ways cars might evolve in the near future.
Hy-Wire Basics
Two basic elements largely dictate car design today: the internal combustion engine and mechanical and hydraulic linkages. If you've ever looked under the hood of a car, you know an internal combustion engine requires a lot of additional equipment to function correctly. No matter what else they do with a car, designers always have to make room for this equipment.
The same goes for mechanical and hydraulic linkages. The basic idea of this system is that the driver maneuvers the various actuators in the car (the wheels, brakes, etc.) more or less directly, by manipulating driving controls connected to those actuators by shafts, gears and hydraulics. In a rack-and-pinion steering system, for example, turning the steering wheel rotates a shaft connected to a pinion gear, which moves a rack gear connected to the car's front wheels. In addition to restricting how the car is built, the linkage concept also dictates how we drive: The steering wheel, pedal and gear-shift system were all designed around the linkage idea.
