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Different realizations of adaptive cruise control systems (ACC) have been tested. Firstly, only throttle access has been realized. In addition to this, the second realization utilizes access to the automatic transmission ECU. Finally, the third realization includes access to the brakes. Essentially, the first two versions are characterized by different states (e.g. acceleration, hold speed, deceleration), while the third version is based on continuous longitudinal vehicle control, e.g. using fuzzy methods [1]. Practical results showed high system stability for all three ACC versions. Advantages and disadvantages of each realization have been worked out based on simulated and measured results. Measurements showed that the first two solutions are sufficient to handle many traffic situations. However, in comparison with these versions, the third realization turned out to be the most powerful one.

The influence of vehicle and driving situation parameters in a rollover event are evaluated by numerical simulation. Sensors and an algorithm for the deployment decision are necessary for occupant protection with restraint systems. The algorithm must decide in a timely manner to deploy the restraint systems for various rollover scenarios. Given the great variety in rollover situations a numerical vehicle simulation is needed and is the suitable tool to cover all cases. All the different cases were divided into 6 test configurations for this simulation investigation. The computer programs ADAMS and MADYMO were used for the rollover simulation. The results from the vehicle dynamic simulation are the sensor input signals for the algorithm (angular rate and acceleration signal) and these signals are also the values for the MADYMO occupant simulation. In addition, the requirements for the restraint system activation in the different rollover scenarios are also obtained from MADYMO.

Safety-critical electronic control units within automotive applications, such as four-wheel-drive, anti-lock braking systems, and airbag systems, are all characterized by sophisticated internal and external monitoring circuitry. This paper is focused on the specific needs of monitoring circuitry in electronic control units (ECU) for airbag systems. After a short introduction, the main electrical components of an airbag system and their interconnections are described. In the following sections, the monitoring of components external to the ECU is discussed, such as the monitoring of the battery supply voltage, the warning lamp, the selection inputs, the firing loops, and external crash sensors. For each case, requirements are stated and practical solutions for the realization of the monitoring functions are provided. Furthermore, the pros and cons of simple and sophisticated solutions are compared.

One important topic in future automotive safety systems will be a better protection of the occupants in rollover situations. Convenient systems are belt pretensioner and head airbags and, for convertibles, rollover bars. For an in-time detection of an imminent rollover and an activation of these safety systems by an electronic control unit there can be used different sensors, for example angular rate sensors, accelerometers, tilt switches. All kinds of these sensors were used in a vehicle test program in order to find out the best sensor architecture for this purpose. By use of a rotation table which is controlled according to the signals of the angular velocity sampled in these tests the rotation of the vehicle about the longitudinal axis can be simulated. This test equipment is used for the validation of trigger algorithms for the safety systems.