Braking free: An inventor combines gas and brake pedals for safety

The Naruse Pedal is a combined brake and gas pedal. The bar on the side of the pedal accelerates the car, while pressing down on the pedal activates the brakes. (Tyler Sipe / New York Times News Service)

Masuyuki Naruse, right, assembles his combined brake and accelerator pedal with welder Koji Yonemura in Tamana, Japan. The pedal's design helps prevent unintended acceleration, Naruse says. (Tyler Sipe / New York Times News Service)

Two pedals, inches apart, one for gas and the other for brakes. For years, a Japanese inventor has argued that this most basic of car designs is dangerously flawed.

The side-by-side pedal arrangement, the inventor says, can cause drivers to mistakenly floor the accelerator instead of the brakes, especially under stress. The solution? A single pedal that accelerates the car when pressed with the side of the foot. When the pedal is pushed down, it activates the brakes.

"We have a natural tendency to stomp down when we panic," says the inventor, Masuyuki Naruse, who owns a small factory in Tamana, Japan. "The automakers call it driver error. But what if their design's all wrong?"

Naruse, 74, is one of a handful of people who have designed combined brake-accelerator pedals in an effort to prevent accidents caused by unintended acceleration.

Regulators in Sweden are testing a single-pedal prototype by inventor Sven Gustafsson. In Japan, about 130 cars equipped with Naruse's pedal have been declared street-legal, including Naruse's own Mitsubishi Diamante sedan. He holds patents for the Naruse (pronounced NAH-roo-say) Pedal in Japan, the U.S. and six other countries.

Yasuto Ohama, a security company executive whose Toyota Harrier has one of the pedals, says he switched after his foot hit the gas instead of the brakes and he almost struck a bicyclist.

"I can never go back," Ohama says. "I now have peace of mind, because there's no mistaking when there's only one pedal."

Naruse's pedal, in various versions, has been around for two decades. But until recently, his testimonials fell mostly on deaf ears -- despite many accidents linked to pedal confusion.

In 2009, nearly 6,700 traffic accidents involving 37 deaths and more than 9,500 injuries were thought to have been caused by drivers in Japan mistakenly pushing the accelerator instead of the brakes, according to the Institute for Traffic Accident Research and Data Analysis, a government-affiliated group based in Tokyo. Car-safety specialists say it is likely that tens of thousands of crashes in the U.S. have also been caused by pedal errors.

Researchers have also pointed to the propensity for drivers to press the accelerator instead of the brakes. In experiments in Japan by Katsuya Matsunaga, an engineering and psychology specialist at Kyushu Sangyo University in Fukuoka City, drivers were asked to switch feet from the accelerator to the brakes on cue, at times while accompanied by startling noises. Subjects under stress sometimes hesitated or found it difficult to switch from one pedal to the other, he says.

Naruse's design is a unified pedal, shaped to accommodate the entire foot. On the right side is an accelerator bar. At any point, the driver can push down on the pedal to activate the brakes while automatically releasing the accelerator bar.

"Simply speaking, the conventional pedal setup, which forces drivers to switch back and forth between pedals, is dangerous," Matsunaga says. "Mr. Naruse's pedal works because it takes into account how our bodies work. It makes sure that when we make a mistake, the car stops."