LOCATION COMPUTATION DEVICE AND LOCATION COMPUTATION METHOD

A self-location calculating device of the present invention projects a patterned light onto a road surface around a vehicle, captures and obtains an image of the road surface around the vehicle. When determining that a condition of the road surface around the vehicle changes as much as or more than a threshold value, the self-location calculating device calculates a current position and a current attitude angle of the vehicle in present by adding an amount of change in the attitude to a current position and a current attitude angle of the vehicle which are calculated in a previous information process cycle.