A method for determining estimated vehicle dynamics parameters using a
vehicle parameter estimator, a vehicle condition detector and a rich
steering input detector for estimating vehicle understeer coefficient and
front and rear cornering compliances in real time. The vehicle parameter
estimator receives a front wheel steering angle signal, a rear wheel
steering angle signal, a vehicle lateral acceleration signal, a vehicle
yaw rate signal and a vehicle speed signal, and employs a linear
parameter estimation algorithm for estimating the understeer coefficient,
and the front and rear corning compliance. The vehicle condition detector
receives the front wheel steering angle signal, the rear wheel steering
angle signal, the vehicle yaw rate signal and the vehicle speed signal,
and disables the vehicle parameter estimator if the vehicle is not
operating in a linear region. The rich steering input detector determines
whether the estimated vehicle parameters are reliable and are ready to be
used.