Future cars may be more pleasant to drive, thanks to computers using a technology called "fuzzy logic."
"Fuzzy logic is an easy way to make a car smart. It improves the performance of cars in many, many ways," said Daniel McNeill, a co-author of the new book "Fuzzy Logic," published by Simon and Schuster.Furthermore, unlike artificial intelligence, fuzzy logic is not terribly expensive. "In a sense, it is low-tech high-tech," said McNeill.
Conventional computers are programmed to make black-and-white decisions. If X happens, the computer does Y.
The idea behind fuzzy logic is to program the computer to consider many factors so that it makes decisions that seem appropriate under certain circumstances.
Fuzzy logic is first showing up in automatic transmissions.
General Motors Corp.'s Saturn division already uses fuzzy logic on its automatic-transmission-equipped cars, and Mitsubishi will introduce fuzzy logic on the automatic transmission of its redesigned 1994 Galant.
Mitsubishi says the prime advantages of fuzzy logic transmissions show up on hills. Here's how it works:
Normally, an automatic transmission would stay in overdrive while descending a hill. That requires the driver to use the brakes constantly, possibly overheating them and losing braking efficiency. Uncontrolled descents are generally not considered fun.
The alternative is to manually downshift to a lower gear to help slow the car. The Mitsubishi fuzzy logic transmission is programmed to do that automatically. It considers information from three sensors that provide data on the throttle opening, the vehicle's speed and brake usage.
Pretend the computer is told that the driver is hardly using the throttle at all, but the vehicle is picking up speed.
Also, the computer is told that the driver has touched the brakes several times in a short period of time.
Those three pieces of information would be consistent with a vehicle making a descent.
So, the fuzzy logic computer goes into its clairvoyant mode and predicts the driver would like some help slowing down. It obliges by downshifting a gear.
The Galant's transmission considers information from the same three sensors during uphill work. The idea here is to reduce the constant hunting or shifting from third to fourth gear.
Fuzzy logic was invented in 1964 by Lotfi Zadeh, a professor at the University of California at Berkeley. It has been slow to be implemented in the United States but not in Japan, McNeill said.
In Japan, fuzzy logic has become the rage. There are even fuzzy washing machines with one button. The machines use optical sensors to determine how much dirt is in the water, and then adjusts the cycle accordingly.
McNeill said Mitsubishi is an automotive leader in the use of fuzzy technology and is working on a "total fuzzy car" in Japan that uses fuzzy logic not only on the transmission, but also suspension, four-wheel steering, traction control, four-wheel drive and air conditioning.
Nissan has an automatic transmission in Japan that can reduce fuel usage by 12 percent to 17 percent, according to McNeill's book.
McNeill says the Big Three are all working on fuzzy logic, and he expects it to become far more popular in the United States. But there is a big gap between Japan and the United States in this field, he said.
"Japanese people are very quick to embrace technology for the sake of technology," said one Mitsubishi official. "American people are more skeptical."