Rollover Detection
The E64 Convertible is equipped with a special Crash Safety Module. The module incorporates a special sensor system for detecting rollover situations. On top of the two sensors (4) for longitudinal (X-axis) and lateral acceleration (Y-axis), there is a yaw-rate sensor (2) and a LOW g sensor (3) for the Z-axis and for the Y-axis.
The longitudinal - and lateral-acceleration sensors (4) record the positive and negative vehicle acceleration in a measuring range of 0-100 g. They serve to detect heavy acceleration and deceleration in a crash.
The two LOW-g sensors (3) have a small measuring range of 0-2 g and can therefore detect small accelerations and decelerations with great accuracy. For example, when the vehicle skids sideways off the road surface and buries itself with its wheels in soft ground.
The sensors provide a voltage as measured variable. This voltage is a measure for the acceleration and is converted directly into digital signals in the sensor. The digital values are sent to the processor for evaluation.
The processor evaluates the signals from the longitudinal - and lateral-acceleration sensors and the two LOW g sensors. The yaw-rate sensor is also included in the calculation. The results are compared with the stored algorithm. When the processor detects that a rollover is imminent, it sends two telegrams within a defined timeframe to the ROC ECU with the instruction to trigger the actuators.