Abstract: A measuring apparatus comprises an industrial robot and a sensor fastened to a movable arm of the robot. A calibration body comprises a calibration element, a carrier, and an alignment element rigidly arranged relative to the carrier. The alignment element interacts with a counter piece provided on a carrying structure. Data specifying the pose of the calibration element relative to the alignment element are encoded in an encoding zone which may be embodied as a data matrix code. The calibration body is initially aligned on the carrying structure with the aid of the alignment element and the counter piece. The sensor then approaches the encoding zone to read the data encoded therein. Subsequently, the pose of the calibration element relative to the carrying structure is determined using the previously read data. Finally, the pose of the calibration element is measured by the sensor to calibrate the measuring apparatus.