SLIP STATE DETECTION APPARATUS AND SUSPENSION CONTROL APPARATUS

A suspension control unit includes a slip state detection apparatus configured to detect a slip state of a wheel. The slip state detection apparatus includes a second slip ratio calculation portion, a slip ratio distribution calculation portion, and a third slip ratio calculation portion. The second slip ratio calculation portion determines a tire characteristic-considered slip ratio (a second slip ratio) according to a longitudinal acceleration of a vehicle detected by a longitudinal acceleration sensor (a longitudinal acceleration) and a tire characteristic (a slip ratio coefficient). The slip ratio distribution calculation portion calculates a percentage of a slip ratio of each wheel. The third slip ratio calculation portion determines a corrected slip ratio of each wheel (a third slip ratio) by correcting the tire characteristic-considered slip ratio (the second slip ratio) according to the percentage of the slip ratio of each wheel calculated according to a rotational velocity signal of each wheel.