Motoring journalists have had their first ride in Nissan’s high-tech self-driving car, saying it is similar to being chauffeured by a very cautious person – maybe your grandmother.

Nissan's self-driving car can read traffic lights.

Nissan’s self-driving car can read traffic lights. Image by Martin Abegglen / CC BY-SA 2.0

Requiring neither hands on the steering wheel nor a foot on the accelerator or brakes, the Nissan making its way on Japanese public roads is instead packed with radars, lasers, cameras and computer chips.

Nissan’s “intelligent driving” feature is smart enough to navigate junctions without lane markers. It also brakes safely to a stop without crashing into the vehicle in front and it knows the difference between a red light and a tail-lamp.

Reporters were given a half-hour test ride in the prototype vehicle on a scenic but pre-programmed course on Tokyo roads, which included stopping at traffic lights, making turns, changing lanes and crossing a bridge across the bay.

The car was painstakingly careful, like someone extra cautious on the road. It always stayed within the speed limit. And it slowed down, appearing to be “thinking” at slightly complicated situations, such as cars coming from another lane.

Nissan is preparing the autonomous driving option for vehicles going on sale in 2020. It plans to have abbreviated versions of the technology starting from next year, such as keeping a safe distance from the car in front on congested roads.

The car is still unable to deal with unexpected situations, such as moving to the side of the road if an ambulance approaches. At one point, the human driver, who was in the seat for the whole test ride, had to intervene because the car did not properly recognise a lane drawn rather obscurely.

Nissan general manager Tetsuya Iijima, the human driver for the test ride, acknowledged the system needed fine-tuning but was confident it was the way of the future, delivering better safety, because more than 90% of traffic accidents are caused by driver error.

When compared with a human, Nissan’s prototype is only three or four years old, maybe six at most, and the goal is to help it mature to a 20 year old, he said.

“It’s like a kid,” said Mr Iijima, emulating a child walking slowly, a step at a time. “We need to make it understand the world – the severe world.”

The system was shown in Nissan’s Leaf electric vehicle, meaning it was not only intelligent but also zero-emission.

Its boot space was filled with electronics and wiring, evidence of the computer technology needed to integrate the information from the car’s many sensors, radars and 360-degree cameras. But when it goes on sale, the electronics system will be much smaller and tidier.

Jeremy Carlson, senior analyst at IHS Automotive, an expert on autonomous driving, praised Nissan for having “a clear road map” for the technology it was working on.

“Nissan’s plans to successively deploy piloted drive technologies keep the auto-maker at or near the leading edge of the industry in driver assistance technology, both in Japan and worldwide,” he said.

“Overall it is a comprehensive system that will allow Nissan to continue to innovate and add functionality in the future.”

Nissan plans to tailor the feature to various markets.

In the US, where there tends to be long driving on highways, a feature that might work like an enhanced auto-cruise would be handy.

All the major car makers, including Nissan’s Japanese rival Toyota and electric car maker Tesla Motors, as well as players outside the industry such as Google, are working on the driverless car. Daimler and Mercedes Benz have also developed such technology.

“We think we are a leader,” Mr Iijima said. “Please compare the prototypes.”

(Press Association)