Siemens' Fingerprint Recognition - Theft Prevention System
6 March 2000
It's Not Science Fiction AnymoreDETROIT - A driver enters his vehicle, presses his finger to a sensor in the instrument panel which starts the engine and initializes a series of vehicle personalization events. No, this isn't a scene from a James Bond movie. It is technology developed today at Siemens Automotive that is being demonstrated in the Siemens Automotive booth at the SAE show, in Detroit. Many products in the automotive industry have evolved from existing technologies applied in other fields. Two years ago, the electronics for vehicle access control and driver authorization were installed into a Smart Card, slightly thicker than a credit card. Siemens Automotive's PAssive Start/Entry (PASE) marked the first implementation of this concept in the 1999 Mercedes S-Class. That technology has since evolved into the science of biometrics, the application of mathematical, statistical theory to biology -- or fingerprint recognition. According to Siemens' engineers in Regensburg, Germany, fingerprint recognition will be ready for production in two years. As the driver slightly touches the fingerprint switch, the skin of the fingertip with its individual and unmistakable geometric characteristics is sensed. A high-performance computer reads, measures and quickly identifies the fingerprint. The engine ignition sequence is authorized and the ignition is started. All of this, measured in fractions of a second, is much faster and more convenient for the driver than a conventional car key and ignition lock. Immediately following the ignition authorization sequence, the automatic transmission receives the control command for the gearshift functions, tailored to the driving style of the unique fingerprint. This intelligent control, or "fuzzy" logic, takes into account changing environmental conditions, as well as personal driving style, adapting the shifting strategy to the conditions and requirements of the driver. Another convenient feature of the system is its ability to adapt the mirror, climate control, radio settings, steering column and seating positions to the driver's individual requirements. When a fingertip is placed on the sensing field for evaluation, 65,000 sensor electrodes measure the exact distance between the skin surface and the sensor. Within fractions of a second, the sensor generates a digitized grayscale image of the fingerprint with a resolution of 20 dots per millimeter (513 dpi). The image processing software searches for one to two dozen characteristic features of the fingerprint, the minutiae, and stores their position and orientation in its memory. During the subsequent check, an evaluation algorithm compares the image sensed to the previously stored reference data. The chip only issues the release signal that activates the system functions if both sets of data are identical. If the quality of the image sensed is impaired by factors, such as when the skin on the fingertip is dirty or injured, the system can read other fingers as the system can be programmed to recognize up to three fingers of the same person. In fact, nearly one hundred reference prints per sensor can be stored. The high degree of integration of the fingertip sensor, memory and computer is Siemens' competitive advantage. A single silicon chip with an area of 160-square-millimeters, approximately the size of a penny, holds the sensing field, analog-digital converter, sequencing control, clock generator and parallel interface. A digital signal processor serves as the evaluation unit. A CAN bus network is used for user guidance and signal transmission to the individual functions. The capacitive fingertip sensor is produced with the same Complimentary Metal Oxide Semiconductor (CMOS) technology used for conventional memory chips, resulting in a number of significant advantages over optical or infrared sensors relative to production costs and space requirements in the vehicle. Fingerprint sensing is expected to provide benefits to Original Equipment Manufacturers (OEM), as well as consumers. Siemens Automotive is a tier-one supplier of automotive and electrical- electronic systems and components with applications covering gasoline and diesel powertrain systems, safety and chassis systems, body electronics, electric motors drives and driver information systems. Worldwide sales in fiscal year 1998/1999 totaled $3.6 billion.