Patent ID: 8649978

Claim:
A velocity calculating device comprising: a vertical acceleration detector mounted on a moving body, the vertical acceleration detector detecting an acceleration in a vertical direction generated due to an undulation of a contact surface that is in contact with the moving body; a horizontal angular velocity detector mounted on the moving body, the horizontal angular velocity detector detecting an angular velocity around a horizontal axis that is perpendicular to a direction of travel of the moving body, the angular velocity being generated due to the undulation of the contact surface; and circuitry configured to calculate a correlation coefficient that represents a degree to which an acceleration in the direction of travel of the moving body is mixed into the acceleration in the vertical direction in accordance with an attachment angle with which a body including the vertical acceleration detector and the horizontal angular velocity detector is attached to the moving body; calculate a true acceleration in the vertical direction by subtracting the acceleration in the direction of travel mixed into the acceleration in the vertical direction from the acceleration in the vertical direction, the acceleration in the direction of travel mixed into the acceleration in the vertical direction being calculated on the basis of the correlation coefficient; and calculate a velocity of the moving body in the direction of travel of the moving body on the basis of the true acceleration in the vertical direction and the angular velocity around the horizontal axis.