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safety

Ben Margot/The Associated Press

They're the symbol of the connected age, eyes glued to smartphone screens as they walk, checking social media feeds, texting, watching videos. Someone even coined a term for them: petextrians.

It's funny when they stumble into fountains or bump their heads on light poles, but not so much when they wander into traffic.

The phenomenon is one reason auto makers are working to perfect electronic safety systems designed to alert drivers to potential collisions with vehicles and pedestrians alike, taking over braking if necessary.

Pedestrian safety is top of mind this time of year. The switch from daylight savings time on Nov. 6 is associated with a spike in pedestrian collisions as darkness falls an hour earlier for the afternoon commute. Nov. 16 is also the national day of remembrance for road crash victims.

After years of decline, U.S. pedestrian fatalities began trending upward in 2010, three years after Apple launched the iPhone. Deaths actually dipped in Canada in 2014 after being relatively flat for years.

Neither Canada nor the United States have data linking proliferation of smartphones to rising pedestrian deaths. The U.S. National Highway Traffic Safety Administration told Globe Drive it's considering a study. Most research focuses on driver behaviour and factors such as pedestrian visibility.

Scott Lindstrom, Ford's manager of driver assist technologies, said testing on three continents to develop Ford's Pre-collision Assist with Pedestrian Detection system show petextrians are a problem.

"We did over 500,000 miles of testing with video data and we analyzed that video data, so we kind of know from that data that it does indeed happen," he said in an interview from Dearborn, Mich.

Ford is introducing its Pre-Collision Assist with Pedestrian Detection system on the 2017 Fusion. It's been available on the European Ford Mondeo and in North America on the Lincoln MKX since last year.

Toyota is offering its Toyota Safety Sense P (for pedestrian) collision-warning system as standard on its redesigned Corolla sedan. Other models that have TSS+P as standard include the Prius, Avalon sedan and RAV4 SUV. A version dubbed LSS+ is offered on most upscale Lexus models.

Most auto makers' systems operate on the same basic principle, a high-mounted camera and millimetre-wave radar behind the grille combine to detect potential collision hazards. Computer software analyzes the images, issues an audible warning and pre-loads the brakes for the driver. But if the driver doesn't react in time, it automatically applies full braking force to avoid a collision or reduce its impact.

The systems are marketed as important safety enhancements – which they are – but they're speed-restricted and they're not infallible.

"Pedestrians have properties of both rigid and flexible objects," says a study posted by the U.S. National Institutes of Health. "Furthermore, the appearances of pedestrians are easily affected by view angle, occlusion, apparel, scale, pose variation, and illumination changes.

"All these issues have made pedestrian detection become a hot issue and one of the difficulties in the fields of computer vision."

The systems rely on image libraries that help recognize objects that may be pedestrians. Ford says its system was developed using 240 terabytes of test data based on track testing and real-world driving conditions.

But the images can be ambiguous – a person carrying a large box across the road, for instance, or half-obscured by a parked car. Most can't reliably alert drivers to pedestrians less than a metre tall – small children.

"It has to be taller than the hood," said Lindstrom. "If it's really short the camera's not going to see it."

Fog and rain also degrade their performance.

"If you can't see it, the car can't see it," said Toyota Canada engineer Terrence Chu.

Systems also have to be tuned to avoid too many false alarms, such as mistaking a stop sign for a pedestrian, which might cause drivers switch them off.

"If you come to a sudden stop in the middle of the road for no apparent reason, we don't think our customers would want that," said Lindstrom.

Insurance Bureau of Canada spokesman Andrew McGrath said both motorists and pedestrians should remain careful and alert.

"These emerging technologies could possibly lead to 'zero fatality' roads," he said. "That being said, staying alert and being cognizant of your surroundings – regardless of whether you have an onboard warning system – goes a long way towards reducing collisions and accidents."

In October, the federal government announced it was making back-up cameras mandatory on all new vehicles for the 2018 model year, bringing Canadian rules into line with U.S. standards. The regulation is largely aimed at helping protect pedestrians.

Toyota vice-president Stephen Beatty said it's possible governments may do the same with front-mounted automated systems in the future.

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