A method for allowing even a user with little experience in robot operation to be able to perform correct calibration is provided. A mobile device displays one or more patterns at predetermined positions and transmits information indicating a touch position to a control device according to touching applied to the touch position in a state that the patterns are displayed. The control device calculates a parameter set based on an image measurement result obtained by a visual sensor when the mobile device is disposed in an image visual field in a state that the patterns are displayed, a touch position when the mobile device is touched by a robot, and a distance between a position of the mobile device when disposed in the imaging visual field and a position when the mobile device is touched by the robot.