1. An information processing method for calibrating a position and orientation of a sensor in an object coordinate system based on an object, the sensor being attached to the object used to measure a position and orientation of the sensor in a world coordinate system, and a position and orientation of the sensor in the object coordinate system is stored in a storage unit, the information processing method comprising: an image input step of inputting an image of the object captured by an image capturing device; a sensor measurement value input step of inputting a measurement value of the position and orientation of the sensor in the world coordinate system; an index detecting step of detecting information about image coordinates of an index attached to the object from the image, wherein a position of the index in the object coordinate system is known; a position and orientation input step of inputting a position and orientation of the image capturing device in the world coordinate system; a relative position and orientation calculation step of calculating a relative position and orientation between the index attached to the object and the image capturing device on the basis of the measurement value of the position and orientation of the sensor in the world coordinate system input in the sensor measurement value input step and the position of the index in the object coordinate system; an image coordinates calculation step of calculating image coordinates of the index in the image on the basis of the position of the index in the object coordination system, the relative position and orientation calculated in the relative position and orientation calculation step, and the position and orientation of the image capturing device input in the world coordinate system in the position and orientation input step; a difference calculation step of calculating a difference value with the image coordinates detected in the index detecting step and the image coordinates calculated in the image coordinates calculation step; a correction value calculation step of calculating a correction value of a position and orientation of the sensor in the object coordinate system on the basis of the difference value calculated in the difference calculation step and the relative position and orientation calculated in the relative position and orientation calculation step; and a calibration step of calibrating the stored position and orientation of the sensor in the object coordinate system on the basis of the correction value.