Movement condition determination

摘要

A velocity information acquisition section 21 acquires velocity information on the velocity of a vehicle and records this acquired information in a velocity information recording section 27. A state judgment section 23 judges start and stop states of the vehicle based on state information indicating the start and stop states of the vehicle that was acquired at a state information acquisition section 22. After this judgment, a minimum output velocity computing section 24 accurately computes, based on the velocity information recorded in velocity information recording section 27, a minimum output velocity in a period in which a vehicle velocity detection circuit 10 cannot detect velocity information. A movement condition computing section 25 can appropriately compute a relative movement distance or a relative movement velocity of the vehicle based on the state information acquired at state information acquisition section 22 and the minimum output velocity computed at minimum output velocity computing section 24. <IMAGE>