· Acceleration and yaw rate sensors can be integrated for all axes

· Lower system costs and less installation space needed

Lower overall costs and reduced space requirements – these are the outstanding characteristics of the Bosch AB plus airbag control unit. In the existing housing of the airbag control unit, engineers have integrated two sensors of the ESP® electronic stability program. The inertia sensors – i.e. the sensor elements used to measure yaw rate and lateral acceleration – used to have their own separate housing. This is now no longer necessary. In addition, further acceleration sensors and yaw rate sensors can be integrated, allowing vehicle movement along all axes to be measured. “AB plus offers our customers improvements in two key areas – it frees up installation space and keeps system costs low,” says Dr. Werner Struth, president of the Bosch Chassis Systems Control division. Bosch AB plus recently debuted in a production car made by a Japanese automaker.

Both the ESP® anti-skid system and the passenger restraint system require extremely accurate data about the actual movement of the vehicle. The sensors needed to supply these data have so far been positioned as close as possible to the vehicle’s center of gravity. Combining the two sensor blocks saves costs. This integrated concept is best suited for vehicles in which both airbags and ESP® are standard features. One further advantage, apart from the fact that there is no need for a separate housing and less space is needed for installation, is that electrical connections can be made more easily.

The AB plus control unit offers all the conventional crash-sensing functions for passive safety: as well as sensing head-on, side, and rear crashes, a rollover sensor function is also available as an option. Moreover, an active pedestrian protection system can also be integrated. The system can be scaled flexibly with respect to the number of spark plugs, of sensor interfaces for peripheral crash sensors, and of integrated inertia sensors. Because the inertia sensors are directly connected to the motherboard in the airbag control unit, it is no longer so complicated to offer new functions based on the networking of airbag control unit and ESP®.

Two further Bosch concepts for integration
Apart from AB plus, Bosch offers two further solutions for integrating inertia sensors in existing control units. Since 2008, for example, there has been an ESP® variant in series production in which the sensors are integrated in the ESP® control unit itself. It is mounted directly on the hydraulic modulator and installed in the engine compartment. Integrating sensors in the ESP® is always an advantage in vehicle models in which this anti-skid system is not a standard feature. If even more sensors or control units are to be combined, then the domain control unit (DCU) is the more suitable approach. In this central control unit, the software of new functions, as well as individual hardware components and sensors, can be combined in a compact unit.

The Bosch Group is a leading global supplier of technology and services. In the areas of automotive and industrial technology, consumer goods, and building technology, some 275,000 associates generated sales of 38.2 billion euros in fiscal 2009. The Bosch Group comprises Robert Bosch GmbH and its more than 300 subsidiaries and regional companies in over 60 countries. If its sales and service partners are included, then Bosch is represented in roughly 150 countries. This worldwide development, manufacturing, and sales network is the foundation for growth. Each year, Bosch spends more than 3.5 billion euros for research and development, and applies for some 3,800 patents worldwide. With all its products and services, Bosch enhances the quality of life by providing solutions which are both innovative and beneficial. The company was set up in Stuttgart in 1886 by Robert Bosch (1861-1942) as “Workshop for Precision Mechanics and Electrical Engineering.” The special ownership structure of Robert Bosch GmbH guarantees the entrepreneurial freedom of the Bosch Group, making it possible for the company to plan over the long term and to undertake significant up-front investments in the safeguarding of its future. Ninety-two percent of the share capital of Robert Bosch GmbH is held by Robert Bosch Stiftung GmbH, a charitable foundation. The majority of voting rights are held by Robert Bosch Industrietreuhand KG, an industrial trust. The entrepreneurial ownership functions are carried out by the trust. The remaining shares are held by the Bosch family and by Robert Bosch GmbH. Additional information can be accessed at www.bosch.com.

PI6837 - December 2009