Hd. Taghirad et E. Esmailzadeh, AUTOMOBILE PASSENGER COMFORT ASSURED THROUGH LQG LQR ACTIVE SUSPENSION/, Journal of vibration and control, 4(5), 1998, pp. 603-618
An analytical investigation of a half-car model including passenger dy
namics, subjected to random road disturbances is performed, and the ad
vantage of active over conventional passive suspension systems me exam
ined. Two different performance indices for optimal controller design
are proposed. The performance index is a quantification of both ride c
omfort and road handling. Due to practical limitations, all the states
required for the state-feedback controller are not measurable, and th
us must be estimated with an observer. Stochastic inputs are applied t
o simulate realistic road surface conditions, and statistical comparis
ons between passive system and the two controllers, with and without s
tate estimator, are carried out to gain a clearer insight into the per
formance of the controllers. The simulation results demonstrate that a
n optimal observer-based controller, when including passenger accelera
tion in the performance index, retains both excellent ride comfort and
road handling characteristics.