Text: B.T. Yu / Photos: Brent Co, Jude Morte | posted May 26, 2009 09:28
Volvo's new City Safety system
Volvo's newest model, the elegant XC60, serves as the flagship car featuring the City Safety driver support system. City Safety is designed chiefly to help prevent low-speed collision. According to Volvo's research, 75% of car accidents occur at a speed of 30 km/hr or less. This means distracted drivers failing to notice that the car in front has stopped or has slowed down, and had had no presence of mind to slam on the brakes on time. City Safety is the world's first ever technology that stops a car moving at 18-30 km/hr from hitting a vehicle in front. It detects objects up to 18 feet in front of the bumper through a laser sensor mounted behind the rearview mirror. If a shape 6-8 meters in front with a size approximately that of a passenger car is at a standstill or is moving at a slower speed, City Safety engages the brakes and reduces the throttle opening to get ready for the driver's brake. If the driver doesn't respond, City Safety automatically applies the brakes and switches off the throttle. The car stops for just 3 seconds before rolling on again, enough time for a driver to regain concentration.
This writer was able to experience this feature through the XC60 first hand in a controlled facility across Volvo's Makati showroom. 100 meters away from the starting line was a balloon replica of a vehicle. This driver was instructed to accelerate until 25 km/hr and then let go of the gas, letting the car approach the balloon at a steady speed. As we neared the object, I felt the car slow down and with a jerk come to a full stop. The slowing down made me instinctively go for the brake, but the instructor told me to let go. After a couple of seconds, the car moved again albeit slower until it finally nudged the balloon in front. The sudden stop is enough to jerk a sleepy driver awake, and the drop in speed just before the automatic brake is sufficiently noticeable for a distracted driver to come to. Thanks to the automatic brake, the impact on balloon would have equated to nothing more than a paint scratch, as opposed to a dent without the City Safety.
At normal to high speeds, Volvo ensures safety by introducing the Pre-Prepared Restraints technology, also featured in the new XC60. Designed to help reduce injuries from collision, the PRS combines the functions of the laser sensor with other protective and preventive safety systems. In case of an impending collision, the laser sensor feeds information to the airbags and adaptive seat belt load limiters to suit the gravity of the impact. PRS is active at all speeds, unlike City Safety which only works until 30 km/hr. Also, City Safety can be turned off although it is always on by default.
The City Safety ranks high in my list of Most Impressive Things Seen This Year. It is a reason for any urban dwelling motorist to rejoice. However, it does not give drivers license to grow lax and abandon good driving habits. The City Safety will not register approaching vehicles, nor will it recognize motorcycles, cyclists, and most importantly, pedestrians (boo!). City Safety has other limitations as well. For instance, visibility factors like fog, heavy rain, snow and dirt affect the laser's detection, although when something is blocking the sensor, the driver is alerted by a message in the information display. In terms of the reliability of the auto-brake, the system makes 50 calculations a second to determine the braking force needed to prevent a collision, but surface quality would affect the performance of this function.
It does seem like Volvo has got it all covered in terms of safety. However, as all devices go, technology does not eliminate danger without the cooperation of the user. Without these bonus additions to one's vehicle, a responsible, conscientious and disciplined motorist is all that it takes to have a safe, hassle-free driving experience. Now, if only the City Safety had come out earlier when I was in college?