IN FUTURE WITHOUT DRIVERS,DO CARS EXIST

        Carmakers are developing vehicles that have an increasing ability to autonomously drive themselves, potentially reducing accidents and traffic congestion.

A silver BMW 5 Series is weaving through traffic at roughly 120 kilometers per hour (75 mph) on a freeway that cuts northeast through Bavaria between Munich and Ingolstadt. I’m in the driver’s seat, watching cars and trucks pass by, but I haven’t touched the steering wheel, the brake, or the gas pedal for at least 10 minutes. The BMW approaches a truck that is moving slowly. To maintain our speed, the car activates its turn signal and begins steering to the left, toward the passing lane. Just as it does, another car swerves into the passing lane from several cars behind. The BMW quickly switches off its signal and pulls back to the center of the lane, waiting for the speeding car to pass before trying again.

      Putting your life in the hands of a robot chauffeur offers an unnerving glimpse into how driving is about to be upended. The automobile, which has followed a path of steady but slow technological evolution for the past 130 years, is on course to change dramatically in the next few years, in ways that could have radical economic, environmental, and social impacts.

The first autonomous systems, which are able to control steering, braking, and accelerating, are already starting to appear in cars; these systems require drivers to keep an eye on the road and hands on the wheel.

But the next generation, such as BMW’s self-driving prototype, could be available in less than a decade and free drivers to work, text, or just relax. Ford, GM, Toyota, Nissan, Volvo, and Audi have all shown off cars that can drive themselves, and they have all declared that within a decade they plan to sell some form of advanced automation—cars able to take over driving on highways or to park themselves in a garage. Google, meanwhile, is investing millions in autonomous driving software, and its driverless cars have become a familiar sight on the highways around Silicon Valley over the last several years.

The allure of automation for car companies is huge. In a fiercely competitive market, in which the makers of luxury cars race to indulge customers with the latest technology.

Thanks to autonomous driving, the road ahead seems likely to have fewer traffic accidents and less congestion and pollution. Data published last year by the Insurance Institute for Highway Safety, a U.S. nonprofit funded by the auto industry, suggests that partly autonomous features are already helping to reduce crashes. Its figures, collected from U.S. auto insurers, show that cars with forward collision warning systems, which either warn the driver about an impending crash or apply the brakes automatically, are involved in far fewer crashes than cars without them.

More comprehensive autonomy could reduce traffic accidents further still. The National Highway Traffic Safety Administration estimates that more than 90 percent of road crashes involve human error, a figure that has led some experts to predict that autonomous driving will reduce the number of accidents on the road by a similar percentage. Assuming the technology becomes ubiquitous and does have such an effect, the benefits to society will be huge. Almost 33,000 people die on the roads in the United States each year, at a cost of $300 billion, according to the American Automobile Association. The World Health Organization estimates that worldwide over 1.2 million people die on roads every year.

Meanwhile, demonstrations conducted at the University of California, Riverside, in 1997 and experiments involving modified road vehicles conducted by Volvo and others in 2011 suggest that having vehicles travel in high-speed automated “platoons,” thereby reducing aerodynamic drag, could lower fuel consumption by 20 percent. And an engineering study published last year concluded that automation could theoretically allow nearly four times as many cars to travel on a given stretch of highway. That could save some of the 5.5 billion hours and 2.9 billion gallons of fuel that the Texas Transportation Institute says are wasted by traffic congestion each year.

If all else fails, there is a big red button on the dashboard that cuts power to all the car’s computers. I practiced hitting it a few times.

But such projections tend to overlook just how challenging it will be to make a driverless car. If autonomous driving is to change transportation dramatically, it needs to be both widespread and flawless. Turning such a complex technology into a commercial product is unlikely to be simple. It could take decades for the technology to come down in cost, and it might take even longer for it to work safely enough that we trust fully automated vehicles to drive us around.