Drivers have depended on gestures to maneuver through traffic since the dawn of the auto age, from a friendly wave to a shaking fist -- or worse.
Now, automakers are starting to use gestures to let drivers control car functions, whether it's an approaching hand to activate a dashboard infotainment system or the kick of a leg to open a crossover's tailgate.
Not only are the latest gesture technologies on display this week at the International CES here, but more will be featured at the North American International Auto Show in Detroit next week.
Hyundai plans to introduce a sleek concept car that incorporates "3-D gesture" control so a driver can operate an audio system with the wave of a hand.
The goal: Make it "safe and easy to use," says Mitchell Zarders, a Hyundai senior engineer, who notes the functionality is still in its infancy. "You are going to be amazed in a couple years. (Gesture control) isn't going to resemble anything that you see today."
As with so many promising technologies, interest in the use of gestures to make things happen inside and outside cars isn't so much the product of a breakthrough as it is a confluence of events.
First is safety. Designers are striving to find ways that drivers can avoid fiddling for buttons, knobs or icons on an electronic display screen as a car barrels down the road at 70 miles an hour. The use of voice commands to change radio stations, phone home or search for an address is becoming common. The ability to wave a hand, rather than having to glance at the dashboard, is considered a natural next step in the war against driver distraction.
Three of four consumers said safety is the top consideration in buying a car, according to a survey of 2,100 people released this week by auto parts supplier Johnson Controls. Safe operation of systems is considered critical.
Consumers have already seen the potential for motion sensors and gesture control in other aspects of their lives, whether it's outside floodlights that automatically illuminate when a critter prowls the backyard or playing group-oriented video games.
From mock bowling to disco dance contests, millions of players have discovered how video games monitor and mimic their body motions using systems such as Microsoft's hands-free, body-sensing Kinect controller for the Xbox 360, Sony PlayStation Move or Nintendo Wii remotes.
"Three-year-olds are touching the TV, expecting it to move," says Parrish Hanna, global director of human-machine interface programs for Ford Motor. "Between consumer electronics and automotive, there is going to be a constant struggle" for higher levels of technology, including gesture control.
Car buyers have come to expect the same wizardry in vehicles as they find in consumer products at home. New cars are being loaded with sensors and cameras. Using radar, they can parallel park themselves or hold their place in stop-and-go traffic. Even driverless cars, shown at the consumer electronics show this week, are on the horizon with the help of laser-ranging systems.
Here's how gesture technology is showing up in cars.
Drowsy driver detection. Lexus has mounted an infrared camera to steering columns of 2013 GS and LS luxury sedans that "maps" drivers' faces, searching for signs they're looking away from the road or falling asleep.
The system works in conjunction with the car's radar to detect another vehicle or object that could mean a crash is imminent. Then, the car automatically brakes and cinches the seat belts to prepare for a collision.
Using gesture recognition means the system "will activate a tenth or a hundredth of a second earlier" than radar alone. General Motors and other automakers are researching similar driver-monitoring systems. "We are watching the head," not just the eyes, "and checking to see if there is tilting," to indicate drowsiness, says GM engineer Mike Hichme.
Opening doors. Moms, dads or shoppers can wave ankles under the tailgate of a Ford Escape or C-Max family hauler to get it to open when their arms are filled. Sensors underneath the bumper detect the leg motion.
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