Suspension control system

A suspension control system for a vehicle provided with a variable damper that can adjust a damping force according to an input signal, comprising:

• a wheel rotational speed sensor for detecting a wheel rotational speed;
• an un-sprung load computing means for computing an un-sprung load of the vehicle according to a wheel rotational speed variation detected by the wheel rotational speed sensor, the un-sprung load consisting of a road contact load variation of the vehicle;
• a state variable computing means for computing state variables of the vehicle by feeding the un-sprung load to a vehicle model representing a behavior of a sprung mass and an un-sprung mass of the vehicle in relation to the un-sprung load, the state variables including a sprung velocity and a suspension stroke speed of the vehicle;
• and
• a damper control means for controlling the damping force of the variable damper according to the computed state variables,
• wherein the un-sprung load computing means converts the wheel rotational speed variation into the un-sprung load based on a relationship between the wheel rotational speed variation and the un-sprung load, the relationship being predetermined based on actually detected values of the wheel rotational speed and a road contact load.