Description And Operation: Description: Accelerometers

WARNING: This page is about a different car, the 2018 Jaguar XE and 2017 Jaguar XE. However, it is still accessible from the selected car via links, so may be relevant.

Three accelerometers are used in the adaptive damping system; two at the front of the vehicle and one at the rear.

The accelerometers measure acceleration in the vertical plane and output a corresponding analogue signal to the SUM. The algorithms in the pulse width modulation calculate the heave, pitch and roll motions of the vehicle, which are used by the SUM. to control body motion.

Each accelerometer is connected to the SUM via three wires, which supply ground, 5 V supply and signal return.

The sensing element comprises a single parallel plate capacitor, one plate of which moves relative to the other dependent on the force (acceleration) applied. This causes the capacitance to change as a function of applied acceleration. This capacitance is compared with a fixed reference capacitor in a bridge circuit and the signal is processed by means of a dedicated integrated circuit to generate an output voltage that varies as a function of applied acceleration. The sensors output a signal voltage of approximately 1 V/g ± 0.05 V/g. When the vehicle is stationary, each accelerometer outputs approximately 2 volts.