Lateral Acceleration Sensor: Notes

Application 

Sense the lateral acceleration of the vehicle

Design 

In the interior of the sensor, a small mass element is attached to a movable lever arm which is deflected by lateral acceleration.

Function 

• Between two electrically charged stationary plates having the same polarity, an electrically charged silicon element having the opposite polarity is attached to the end of a cantilever arm.
• Between these three plates, two electric fields are generated by the capacitances C1 and C2.
• The capacitances C1 and C2 change in response to lateral acceleration. This change can be used to calculate the direction and amount of lateral acceleration acting on the vehicle.
• The same sensor can also be used as longitudinal acceleration sensor if it is installed in the direction of travel (e.g. VW 4 motion with Haldex clutch).
• For 0 g lateral acceleration, the sensor produces an output signal with a voltage of 2.5 V.

Other 

• The signal of the lateral acceleration sensor alone cannot trigger an ESP intervention.

  The sensor is mainly used for estimating the coefficient of friction.

• The installation location of the lateral acceleration sensor is more critical than that of the yaw-rate sensor (lever arm).
• The installation location may not be changed after repairs.