DETROIT - Car keys carry security code emitters that let them start the car, but a new system by German firm Witte Strattec and Yazaki North America Inc. allows drivers to simply turn a knob to crank the engine.
Strattec's system, which also locks and unlatches car doors, depends on lightning-fast low-power radio communication between the car and a pocket-carried key fob for the driver. Strattec brands it as a 'Passive Ignition Lock,' while Yazaki refers to it as a trademarked 'PersonalAccess' system.
The system was displayed on a Volkswagen Passat at the SAE World Congress in Detroit in early March.
The systems are similar to the 'Smart Card' technology that Siemens Automotive supplies to Mercedes-Benz for the CL coupe in Europe.
The driver carries a card that communicates with the car via radio waves and energies the ignition system. The driver starts and stops the engine by touching a button on the gear shift lever.
James Edgar, advanced development engineer at Strattec's Milwaukee development facility, said the system eliminates the need for a mechanical key, but keeps both the proven technology of ordinary steering column locks and the reassuring 'feel' drivers are accustomed to when starting their cars.
'One of our goals was to make this just transparent to use,' Edgar said.
When a driver enters the car, they come in range of special low-power antennas, which interact with the key fob.
As the driver pushes in the steering column knob, the car wakes up and sends a radio frequency query to the fob.
The fob broadcasts back, and within about 90 milliseconds the ignition unlocks itself so that the driver can turn it. The activation is so fast that the driver rarely senses the process; it takes most people more than 150 milliseconds to rotate a standard ignition lock.
The same kind of authorization/unlock procedure works with door latches, as well. A driver approaching the car pulls on the door latch, and the radio frequency broadcast both unlocks the car door and opens the latch just as the door handle reaches its outer limit of travel.
For safety, though, if the door is being opened from the inside, the system only unlocks the door, but leaves the latch opening for manual means. A small child, who partially pulls the door handle, can't inadvertently trigger the unlatching mechanism.
Edgar says the system finally defeats the common driver experience of having a would-be passenger jam an electronic door lock by pulling the handle just as the driver triggers the 'unlock' switch. The driver's passive entry command both unlocks and unlatches the door - even if the passenger is pulling on the handle at the time.
Zach Rowland, Strattec director of electrical engineering, said the passive systems are similar to simpler, robust security systems introduced on 3,000 Utilimaster trucks delivered to Federal Express on the West Coast in 1998.
The system for the delivery trucks, which adds about $1,000 to the vehicle price, is meant to combat pilfering or truck theft that was happening when a truck door had to be left open while deliveries were being made.
Drivers of the Federal Express trucks wear a small radio-frequency wristband that lets them close and lock doors sequentially as they leave the driver's seat, open the freight door, walk around the vehicle or leave it unattended for a delivery or a break.
The wristband not only serves as a door-locking device, but also prevents the truck from being moved if the wristband wearer is outside the truck because it must be near the ignition for engine startup.
Since the system's introduction, pilferage rates on those trucks have dropped to near zero, Rowland said.
Remote keyless entry systems are a hotly competitive area, and Strattec and Yazaki's system for passenger cars has competition from Aisin, Gecom Corp., Honda Lock Manufacturing Co. Ltd., Robert Bosch Corp. and Magna International, among others.
But Edgar and Yazaki project engineer Dale Liff believes their system offers drivers a reassuring feel of traditional door lock and ignition lock controls, while incorporating keyless advanced technology.
'It's why we integrated our standard key fob, with typical control buttons, into the radio frequency function. Most people aren't ready to give up their keys and buttons yet,' Liff said.
The systems still will come with a key, just to reassure drivers - even though there really isn't any place in the ignition module to put it.