'Smart Lights' Illuminate Dark Corners

By using electronics to create "smart" headlights, Ford Motor Co. engineers have found a better, more cost-effective way to illuminate the road ahead.

Ford's system, known as adaptive lighting, is significant because it enables the giant automaker to light the way for luxury vehicles without resorting to High Intensity Discharge (HID) lighting, which can cost hundreds of dollars more than conventional halogen lights.

"This covers the same area as HID," notes Mahendra Dassanayake, staff technical specialist in charge of optical electronics for Ford. "But with this, consumers don't have to get the sticker shock of HID."

Ford's system is specifically targeted at turning situations, especially those in which drivers must venture onto very poorly-lit roads. The system enables drivers to see the dark road they are turning onto by swiveling the head lamps faster than the car itself is turning. Thus, drivers are provided with an early view of the new road, enabling them to glimpse pedestrians, bicyclists or other obstacles before they might ordinarily see them.

The feature accomplishes that by employing stepper motors behind each headlight, and then operating the motors with a controller that responds to vehicle sensors. During operation, the unit's controller "listens" to input from a steering wheel sensor (usually a Hall Effect switch or an optical sensor) and from ABS-based wheel-speed sensors. By "knowing" how fast the car is traveling and how sharply it is turning, the controller is able to calculate where the headlights should be pointing and how fast they should move there. With that information in hand, the system then sends a command signal to the stepper motors, which swivel the gimbal-mounted lights to point at the correct spot.

"It swings the beam into the turning lane faster than the car can get there," Dassanayake says. "So it gives the driver the ability to see farther during a left turn." Specifically, Ford says it provides a sight-distance improvement of about 35 ft.

Ford, which will employ the concept on a Lincoln cross-over vehicle debuting this fall, says it eventually plans to combine the adaptive lighting concept with a secondary row of light-emitting diodes on the sides of the vehicle. Plans are for the LEDs to turn on sequentially, depending upon the speed and turning rate of the vehicle. Ford has not said when the LED configuration will be employed, but the company has said it plans to use the adaptive lighting concept on as many as eight different vehicle models.

"To get better illumination, everyone has been moving to HID," Dassanayake says. "But we believe you get safe and comfortable illumination without all that extra cost."