Intelligent Tires for Commercial Vehicles; Tire Sensors by Siemens VDO Better Protect Driver and Machine

HANOVER, Germany--Oct. 1, 2004--Correct tire pressure is a decisive factor in truck safety. For this reason, Siemens VDO Automotive AG and Goodyear Tire and Rubber Company have optimized the Tire IQ system for use in trucks. The system could prevent 85 percent of all tire damage. The Tire IQ system is suitable for increasingly popular super single tires and will reduce carrier costs since needed tire changes can be planned in advance.

Truck tires and car tires work in the same way. A tire filled with the correct amount of air will smooth bumps in the road, protect the load, driver and passengers, and provide required traction in difficult road conditions. If the pressure is too low, the tires do not function correctly, and will compensate with increased flexing. The tire's interior material experiences much greater motion, becomes hotter and ages more rapidly. In extreme cases, the air suddenly escapes, and the truck or trailer becomes impossible to handle. This situation is responsible for 85 percent of all truck tire failures. Continuous tire pressure monitoring is provided by the Tire IQ system, the intelligent tire pressure sensor system optimized by Siemens VDO Automotive and Goodyear for commercial vehicles.

Intelligent tires provide timely notification of low tire pressure and when older tires need to be changed. This can prevent accidents caused by tire damage. The Tire IQ system can be integrated in twin tires and is suitable for super single tires, the very wide tires for trucks. Super single tires' reduced road resistance lowers fuel consumption and their reduced weight in comparison to classic twin tires increases truck payload.

Siemens VDO and Goodyear originally developed the Tire IQ tire pressure monitoring system for use in passenger cars. In truck tires, the sensor is permanently linked to a 360-degree antenna in the tire material that maintains continuous radio contact with a transceiver-receiver when the vehicle is moving or idling. Electronics in the tire are supplied with energy via a 125 kHz connection. Special evaluation software recognizes pressure loss. The driver receives a specific warning of which tire needs air. In addition, the chip in the tire stores the tire wear and other information to assist in maintenance of leased tires.

The electronics in the tire are a few square millimeters in size and measure both tire temperature and air pressure inside the tire. Since the air pressure changes under parameters such as speed, load and temperature, an algorithm must be used to quickly identify gradual pressure loss. Data about correspondingly equipped tires is sent via the receiver to the software. The electronics evaluate information such as tire rotation speed. The software then uses this information to calculate optimum air pressure. The driver is notified when the measured pressure is below the calculated optimum pressure.

Since the sensor system is integrated in the tire, data such as tire type can be directly transmitted to the vehicle electronics system. In the future, the ABS system or an electronic stability program will benefit from this information. Depending on the tire type and age, corresponding safety systems can intervene in the vehicle dynamics during an emergency.

A press photo accompanying this release can be found at www.siemensvdo.com/press.

Siemens VDO Automotive is a tier-one supplier of automotive electronic/electrical systems and components with applications covering gasoline and diesel powertrain technologies, safety and chassis systems, body electronics, plus interior products including infotainment systems. Worldwide sales reflecting fiscal year 2002/2003 totaled $9.5 billion (EUR 8.375 billion). For more information: www.usa.siemensvdo.com.

Siemens AG is one of the largest global electronics and engineering companies with reported worldwide sales of $80.5 billion in fiscal 2003. Founded more than 150 years ago, the company is a leader in the areas of Information and Communications, Automation and Control, Power, Transportation, Medical and Lighting. With its global headquarters in Munich, Siemens AG and its subsidiaries employ 417,000 people in 192 countries.

With its U.S. corporate headquarters in New York City, Siemens in the USA has sales of $16.6 billion and employs 65,000 people throughout all 50 states and Puerto Rico. Ten of Siemens' worldwide businesses are based in the United States. For more information on Siemens in the U.S.: www.usa.siemens.com.