VEHICULAR STATE ESTIMATION APPARATUS, AND METHOD OF CONTROLLING OPERATION OF ACTIVE SUSPENSION APPARATUS

The vehicular state estimation apparatus includes: a physical quantity detector configured to detect a physical quantity indicating behavior by the vehicle; a vehicle behavior estimator configured to estimate current behavior by the vehicle; a distance sensor that is configured to detect a value pertaining to a distance between the vehicle body member and a measurement point on a road surface in front of the vehicle and corresponding to at least a central section of a road surface contact section on a wheel; a distance calculator configured to calculate a road surface distance; a spring constant calculator configured to calculate at least one of spring constants, in a vehicle stopped state; and a suspension controller configured to control operation of the active suspension apparatus based on the spring constants, the road surface distance, and vehicle behavior information.