“With the wave of a hand” may move from magicians’ banter to car salesman’s description within a few years. Many automakers and suppliers are racing to devise gesture recognition that lets drivers manage complex functions without being distracted.
Hyundai previewed some of its concepts for gesture control of an audio system, letting drivers adjust volume with a hand gesture early this year. Toyota and Microsoft are working together on similar technologies. Volvo’s Concept You uses an infrared (IR) camera to watch the driver’s eyes, turning on displays when the driver looks at them.
Component makers are developing various technologies that can make these concepts a reality. STMicroelectronics and Melexis are both promoting time-of-flight cameras. These IR cameras work a bit like radar, detecting changes in motion rather than creating images.
“Time-of-flight cameras use IR LEDs that are modulated, putting a time stamp on each pulse,” said Vincent Hiligsmann, Marketing Manager for Sensors at Melexis. “By measuring the time it takes for light to reach an object and reflect back, they triangulate distance to very tight resolutions. It works like a motion capture system to detect how a person is moving.”
While these research programs address large movements, other technologies are already starting to see use in touch-sensitive controls. A number of touch screens now have proximity sensing, which lets displays wake from sleep modes when the sensor detects the presence of a hand or finger. The Cadillac User Experience (CUE) system and the 2014 Corvette’s touch screen boasts gesture recognition.
Component suppliers are increasing the range of these proximity sensors so drivers don’t have to reach as far, which can be helpful with some center stack displays. Cypress Semiconductor’s CapSense touch screen sensor can detect fingers when they are nearly a foot away. That makes it feasible to let drivers move their hands up or down to scroll to the next page, among other actions.