Road gradient detection using Kalman filter

Accurate, real-time knowledge of the road inclination is necessary for in-car electronic systems which are related to battery recharging system, electric motor, engine and gearbox control units. When the vehicle is moving, the measurement of the slope is not straightforward. The force measured by the inclination or acceleration sensors is coupled with the force due to the vehicle acceleration. This research examines the application of Kalman filter to estimate the road inclination. Furthermore, it compares the performance of the Kalman filter approach against the acceleration discrepancy method which is currently used by some car manufactures.