DVD-Video System Reaches Automobiles

By Charles J. Murray, EE Times

28-Apr-00

In response to growing demand for automotive video systems, Delphi Automotive has unveiled a DVD-based entertainment device designed to fit in virtually any vehicle.Known as Rear-Seat Audio/Video, the system is a twist on a practice that's been sweeping the automotive industry for two years. Unlike the video tape systems used in a variety of minivans, Rear-Seat Audio/Video is the first automotive video device to offer DVD playback and portability. It can be used in the back seat of a car or carried into a home or hotel room, the company said. Introduced at the recent New York Auto Show, Rear-Seat Audio/Video reflects the sudden and surprising growth of automotive video systems. ""There's a tremendous market pull in that area,"" said Robert Schumacher, Director, Mobile MultiMedia Business Group at Delphi Delco Electronics Systems (Kokomo, Ind.). ""Every manufacturer of vans or large sport utility vehicles either has it in their vehicle or is planning it for the near future. It's now considered a must-have. It really took us by surprise."" Auto-Specific Delphi demonstrated the system on a Buick Cielo concept vehicle at last week's show by placing it atop a rear bench seat, strapping it in with a seat belt and connecting it to the cigarette lighter for power. The system, which measures 20 inches long and 8 inches wide, is said to be small enough to fit atop any rear car seat or truck seat. The system includes the DVD playback unit, a seven-inch liquid crystal display (LCD), user controls and plastic enclosure. Delphi engineers considered developing a video tape unit but decided it didn't offer the portability they wanted. ""The tape playback mechanisms are big and klunky,"" Schumacher said. ""And the tapes themselves are big. It's too hard to stack them."" As a result, he said, they opted for the portability of DVD. Despite its portability, Delphi engineers say the system is specifically designed to meet automotive requirements. Unlike home video systems, which typically operate between 0C to 60C, Delphi's new system is designed for a range of -40C to 85C, which is considered the general specification among automakers for interior electronics. ""If you leave this in the back of a van all night when its ten below outside, the system has to be able to work in the morning,"" Schumacher said. Delphi met those requirements by incorporating a resistance heater into the LCD's back light assembly. The heater helps warm the fluorescent lamps and the display's glass. ""It extends the life of the back light and warms up the liquid crystals so you don't have to wait ten minutes for it to show video motion when it's cold,"" Schumacher said. Engineers also used special high-impact plastics to protect the electronic components from shock and vibration caused by highway driving. Delphi purchased a rugged DVD mechanism from an Asian vendor, which it mounts inside the high-impact plastic enclosure. Although Delphi introduced the system last week as an aftermarket device, the company is already working with OEMs to incorporate it into new vehicles. In most cases, engineers say, the OEM version will use an LCD that folds out of a headliner on the vehicle's ceiling. Some OEMs, however, are considering mounting displays in the back of the front-seat head rests or on the center console. For now, OEM versions of the product probably won't be connected to the vehicle's databus. ""If you've got a video playback system and a screen a few feet away, you don't need a databus,"" Schumacher said. ""But if you have multiple displays around the vehicle, then a databus is more important."" When multiple video displays do become commonplace, Schumacher expects automakers to use fiber optic databuses, such as the Media Oriented Systems Transport (MOST) bus. The next step for the technology, however, is to connect the DVD to the Controller Area Network databus, then run the sound through the vehicle's audio system. That way, users will get the benefit of the new, more-powerful audio systems combined with DVD sound. Advances in this area are inevitable, Schumacher said. ""The initial products will be standalone units, but that's going to change. People are becoming more and more enamored with this technology. They can't seem to get enough of it,"" he said.