A control device for electric power steering apparatus, in which when torque ripples at the time of the rotation of a motor is reduced by simple arithmetic, smooth and safe assist limitation is performed without deteriorating steering feeling, is provided. The water pump pulley is attached by a threaded shaft to a connector on the fan clutch, and the pulley has at least a pair of fasteners each with an exposed fastener head that extends from the pulley’s surface which is next to the fan clutch. This movement information is then used to determine a current positionorientation of the moveable structure. As a result, when distal end portion catches against bending portion, an intermediate reactive force is generated and a base contact load at a final stage of energy absorption can be decreased. This correcting device enables quantitative estimation of size variation occurring in a pattern exposed in lithography and easy and accurate correction of pattern size based on the estimation.