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Smart Cars
Michio Kaku

1 Even the automobile industry, which has remained largely unchanged for the last seventy years, is about to feel the effects of the computer revolution.



2 The automobile industry ranks as among the most lucrative and powerful industries of the twentieth century. There are presently 500 million cars on earth, or one car for every ten people. Sales of the automobile industry stand at about a trillion dollars, making it the world's biggest manufacturing industry.
3 The car, and the roads it travels on, will be revolutionized in the twenty-first century. The key to tomorrow's "smart cars" will be sensors. "We'll see vehicles and roads that see and hear and feel and smell and talk and act," predicts Bill Spreitzer, technical director of General Motors Corporation's ITS program, which is designing the smart car and road of the future.


4 Approximately 40,000 people are killed each year in the United States in traffic accidents. The number of people that are killed or badly injured in car accidents is so vast that we don't even bother to mention them in the newspapers anymore. Fully half of these fatalities come from drunk drivers, and many others from carelessness. A smart car could eliminate most of these car accidents. It can sense if a driver is drunk via electronic sensors that can pick up alcohol vapor in the air, and refuse to start up the engine. The car could also alert the police and provide its precise location if it is stolen.


5 Smart cars have already been built which can monitor one's driving and the driving conditions nearby. Small radars hidden in the bumpers can scan for nearby cars. Should you make a serious driving mistake (e.g., change lanes when there is a car in your "blind spot") the computer would sound an immediate warning. 
6 At the MIT Media Lab, a prototype is already being built which will determine how sleepy you are as you drive, which is especially important for long-distance truck drivers. The monotonous, almost hypnotic process of staring at the center divider for long hours is a grossly underestimated, life-threatening hazard. To eliminate this, a tiny camera hidden in the dashboard can be trained on a driver's face and eyes. If the driver's eyelids close for a certain length of time and his or her driving becomes erratic, a computer in the dashboard could alert the driver.


7 Two of the most frustrating things about driving a car are getting lost and getting stuck in traffic. While the computer revolution is unlikely to cure these problems, it will have a positive impact. Sensors in your car tuned to radio signals from orbiting satellites can locate your car precisely at any moment and warn of traffic jams. We already have twenty-four Navstar satellites orbiting the earth, making up what is called the Global Positioning System. They make it possible to determine your location on the earth to within about a hundred feet. At any given time, there are several GPS satellites orbiting overhead at a distance of about 11,000 miles. Each satellite contains four "atomic clocks," which vibrate at a precise frequency, according to the laws of the quantum theory.
8 As a satellite passes overhead, it sends out a radio signal that can be detected by a receiver in a car's computer. The car's computer can then calculate how far the satellite is by measuring how long it took for the signal to arrive. Since the speed of light is well known, any delay in receiving the satellite's signal can be converted into a distance.

9 In Japan there are already over a million cars with some type of navigational capability. (Some of them locate a car's position by correlating the rotations in the steering wheel to its position on a map.)


10 With the price of microchips dropping so drastically, future applications of GPS are virtually limitless. "The commercial industry is poised to explode," says Randy Hoffman of Magellan Systems Corp. , which manufactures navigational systems. Blind individuals could use GPS sensors in walking sticks, airplanes could land by remote control, hikers will be able to locate their position in the woods -- the list of potential uses is endless.
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11 GPS is actually but part of a larger movement, called "telematics," which will eventually attempt to put smart cars on smart highways. Prototypes of such highways already exist in Europe, and experiments are being made in California to mount computer chips, sensors, and radio transmitters on highways to alert cars to traffic jams and obstructions.

12 On an eight-mile stretch of Interstate 15

ten miles north of San Diego, traffic engineers are installing an MIT-designed system which will introduce the "automated driver." The plan calls for computers, aided by thousands of three-inch magnetic spikes buried in the highway, to take complete control of the driving of cars on heavily trafficked roads. Cars will be bunched into groups of ten to twelve vehicles, only six feet apart, traveling in unison, and controlled by computer.



13 Promoters of this computerized highway have great hopes for its future. By 2010, telematics may well be incorporated into one of the major highways in the United States. If successful, by 2020, as the price of microchips drops to below a penny a piece, telematics could be adopted in thousands of miles of highways in the United States. This could prove to be an environmental boon as well, saving fuel, reducing traffic jams, decreasing air pollution, and serving as an alternative to highway expansion.