The Selfless Volvo: 2011 S60 Pedestrian Detection with Auto Braking System Explained

By Stu Fowle, Photos by Volvo Cars

Mar 15, 2010 - 8:16:00 AM

Last year Volvo debuted the XC60, the “Car that stops itself,” as all the marketing equipment read. This year, they’ll debut a new S60 that’s even smarter, with sharper vision and a more advanced brain. We’re going to call it the “Car that selflessly stops itself.”

Volvo made a name for itself decades ago as the Safety Brand. It claims among its advancements the first three-point safety belt, which debuted fifty years ago and the first side airbag, which debuted with the 1995 850 T-5R and quickly spread soon after through the Volvo range. And those are just a few of the many examples of how Volvo has lead the way. Fatality rates have fallen, advancements have moved on, and today, they leaders of safety face a new challenge. As far as in-car safety goes, everyone has caught up and there’s not a whole lot left to accomplish. What else can Volvo add in a world where other manufactures have pillows of air popping from behind just about every plastic trim panel? It’s time to take a hint from NASA and move this race out into orbit.



By that, we mean advancing on what the XC60 started. Instead of protecting occupants during the event of a crash, it is time for cars to start preventing crashes altogether. Other companies have been working on this in their own ways as well. Many premium marques offer things like blind spot detection systems and lane departure warnings, and there are even other cars that will stop themselves, though most are associated with an optional adaptive cruise control system, while Volvo’s City Safety is standard on every XC60. Up until now, though, it was all about protecting the car and the people inside—no one has ever thought about pedestrians, and that’s both where the S60 leaps ahead and why we’re calling it selfless. Most pedestrians would cause little more than a dented hood or windshield, but that walker might give his or her life in the process.



Advancing beyond the City Safety system's purely laser-based system, Pedestrian Detection with full auto braking uses a combination of radar and video footage, interpreted by a central control unit. A sensor in the grille up front detects objects, then relies on a camera mounted behind the windshield—up out of the way and hidden behind the rearview mirror—to determine what those objects are and where they are moving. It has been trained to identify humans in particular, using a set of size and movement parameters. Children as short as two feet, seven inches tall will be picked up by the camera/radar team.

Says Thomas Broberg, Volvo Senior Safety Advisor, “Detecting pedestrians with sufficiently high reliability has been a complex challenge. Our innovative technology is programmed to trace a pedestrian’s pattern of movement and also to calculate whether he or she is likely to step into the road in front of a car.” His team has been working on the system for five years, driving “more than a half-million kilometers in real traffic to train the system and recognize pedestrians’ patterns of movement and their appearance in different countries and cultures. What is more, we use the information obtained from these tests to conduct advanced computer simulations,” Broberg explains. He’s quite proud of the system, but refuses to say just how many people around the world were frightened by a camouflaged Volvo stopping inches from their knees.

Compared to the XC60’s City Safety, the S60 system uses an all-new dual-mode radar system with a wider field of vision and a higher resolution, which allows it to sense people coming from further out to each side and determine their size and path more accurately. Thanks to upgraded sensors, the S60 will automatically deliver full braking power, whereas City Safety on the XC60 delivers just 50 percent braking force. The camera side of the system works much like a human eye, and has the same limitations. The system can’t see as well in the dark, nor in bad weather. But if you ask us, anyone out walking in the road during a blizzard must have death wish to begin with.

According to Broberg’s research, half of all pedestrian accidents happen with the car traveling below 16 mph. Volvo’s system promises to avoid any collision up to 22 mph, and at least a reduction in speed for anything higher, with a maximum reduction, then, of 22 mph from the original speed. Volvo estimates that if a driver is moving at 31 mph and the system cuts that speed in half by the time a collision happens, the fatality risk is reduced by an average of 20 percent and, in some cases, as much as 85 percent. Leading up to an incident, the S60 will first deliver an audible tone as well as a series of red lights projected on the windshield (simulating a brake light up ahead) before the system takes matters into its own hands and hits the brake pedal.



In addition to Pedestrian Detection, the S60’s new system also integrates all the benefits of City Safety, detecting other cars and preventing accidents up to 18 mph. Volvo claims that over 90 percent of all road accidents are related to some distraction, and that half of all those accidents happen without the driver so much as touching the brake pedal. With the 2011 S60, Volvo looks ready to start shaking up the statistics. In the US, 11 percent of fatalities in traffic accidents are pedestrians. In Europe, that percentage is 14, while in China, it’s a staggering 26 percent.

So much has been done in recent decades to make cars safer, and with this latest advancement, Volvo takes two steps forward, taking those measures not only outside the car, but also, for the first time, putting pedestrians, rather than occupants, first. Some will gripe that this technology is too invasive, that they don’t trust such systems, but this right here is nothing but progress. We applaud Volvo for continuing its efforts to create firsts in a world where it seems like safety can’t go much further. And for working on a system that boasts such a strong value-to-gimmick ratio, which is getting harder to find these days. Cars don’t need to drive themselves, but sometimes stopping having them themselves isn’t such a terrible idea.

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