Yaw-Rate Sensor
A yaw-rate sensor is used to detect rollover.
The yaw-rate sensor has a comb-like structure. It consists of a fixed comb structure (3) and a rotational oscillator (2) with a moving comb structure. Together, the comb structures for a capacitor. The rotational oscillator is fitted on bearings on a shaft (1) in its center.
When the vehicle is in a horizontal position, the rotational oscillator turns within the comb structure and detects the change of direction (left/right). If the vehicle is brought into a tilting position (e.g. on a slope), the rotational oscillator is moved out of the comb structure due to the Coriolis effect.
This causes a change in capacity, which in turn creates a change in voltage proportional to the deflection of the rotational oscillator in the mV range, which is evaluated as the measured variable.
The voltage change is directly related to the angle and, in the same way, the speed of the voltage change is directly related to the angle velocity. The angle and the angle velocity are the measurements used for the algorithm calculation.
The voltage values are directly converted into digital values in the yaw-rate sensor and sent to the main processor for evaluation.