At the 2004 North American International Auto Show in Detroit, Michigan, Volvo Cars presented four new safety systems that will be launched in the company’s car models in the future. One of them was BLIS – Blind Spot Information System. “BLIS is now ready to be demonstrated in roadgoing cars,” says Lex Kerssemakers, Vice President, Global Marketing.
In addition to BLIS, Volvo Cars is also launching water-repellent glass for the side windows and door mirrors – along with a simple and dependable method for switching off the front passenger airbag in Volvo cars.
BLIS – Blind Spot Information System
Despite large window panels and effective door mirrors, there is always the risk of offset rear blind spots while driving. This can increase the risk of accidents, especially when changing lanes or overtaking.
In order to improve safety in such situations, Volvo Cars started fitting its European-spec cars wide-angle door mirrors for the driver’s side back in 1979 – the first car maker to do so. Now the company is taking visibility one-step further with a camera-based monitoring system that keeps a watchful eye on the area alongside and to the offset rear of the car.
When another vehicle enters this zone, a warning lamp comes on beside the appropriate door mirror. The driver is thus given an indication that there is another vehicle very close to his or her own. The system alerts the driver both to cars approaching from behind and cars that have currently been overtaken. The production of BLIS will start in the end of 2004.
The technology behind BLIS
A digital camera that takes 25 pictures per second is installed on each door mirror. By comparing the pictures taken, the system can register when a vehicle is moving within the BLIS zone, which measures 31 feet long by 9.8 feet wide on either side of the car.The system is programmed to identify cars as well as motorcycles, in daylight as well as at night. Since BLIS is camera-based, however, it has the same limitations as the human eye does. This means the system will not function in conditions of poor visibility, for instance in fog or flying snow. In such a case, the driver receives a message that BLIS is not in action. It is also configured not to react to parked cars, road barriers, lampposts and other static objects.
The system is active at all speeds above 6.2 mph. It reacts to vehicles that are driven a maximum of 12 mph slower and a maximum of 43.5 mph faster than the car itself.If the driver chooses, BLIS can be switched off via a button in the centre console.
WRG – Water Repellent Glass
In order to improve safety when driving in the rain, Volvo Cars is launching WRG – Water Repellent Glass – for the door mirrors and front side windows. WRG helps prevent rainwater from obstructing visibility.
On the windows, the water gathers as pearls of moisture, which blow away easily by the wind, leaving a dry glass panel with unobstructed visibility. Since it is more difficult for dirt to fasten on dry surfaces, it is also easier to keep the windows clean and free of ice. WRG treatment requires that the windows be laminated.
On the door mirrors, a different method is used. Here, the water is distributed evenly across the entire glass surface so that it is possible to see through the water. In certain weather conditions, the function can be speeded up if the mirror heater elements are activated. The water repellent function has been created through special treatment of the glass. On the side windows, the treatment must be renewed after about three years and then every year after that in order to ensure full effect. The door mirrors do not need to be re-treated since they are not as exposed to wear and tear.