HOW MANY SENSORS DOES A CAR NEED

The highest rates of growth for sensors have been in the automotive sector. Forecasts (Prognos Studie: Sensortechnik 2000) suggest a 14% annual increase in sales to reach 15 billion DM by 1995. This is due to a spectacular rise in electronic functions in motor cars that started in the seventies. The period up to the eighties was characterized by the substitution of mechanical functions. a trend driven by the need for lower costs, greater reliability and easier system integration. Today, entirely new electronics functions such as exhaust-gas monitoring, active suspension and integrated traffic guidance systems are becoming available. These innovations are driven by the need for manufacturers to produce an attractive range of products as well as more stringent safety, environmental and economic demands. This is where sensors play a key role. Their important tasks include the monitoring of, e.g., the quantity and composition of engine fluids and pollutants, as well as to measure physical parameters of mechanical automotive components and actuators, and the vehicle position and speed with respect to the road. The limits of growth are determined by costs. Measured by the average gross earnings of an industrial worker, the price of a car has remained stable at one yearly gross income during the past 50 years. Opportunities for growth therefore depend purely on the systems benefit of a sensor. This means reducing complexity and costs as well as enhancing the reliability of existing functions and implementing even more sophisticated applications with no significant increase in costs. Microelectronics and sensorics are the kev technologies here. Whereas information density is continuing to increase unabated in microelectronics, thus making individual functions even cheaper, a comparable process is only now starting in sensorics. Apart from the discovery of new effects and the improvement of existing materials, a change toward system integration is occurring on two levels. At the technological level, sensorics and processing are converging. At the logical systems-technology level, sensors are becoming modularized and networked with sensors in other subsectors of the motor car. To achieve the desired benefits in good time, this path toward microsystems technology will also necessitate new structures in research and technology. The key concept here is parallel engineering: in the future, materials research and integration technologies will have even less time to respond to the mandatory requirements of automobile system design. They will have to come up with technology-driven advances. If automotive and sensor engineers cooperate intensively, no limits in growth of sensor utilization can yet be discerned.