A control apparatus controls the controller device that is mounted on a hand of a user and includes a plurality of sensors exceeding the number of fingers of the user to be detected so as to detect bending and stretching of the fingers to be detected. The control apparatus identifies a width of the hand of the user, determines, on the basis of information regarding the identified width of the hand, to which sensor among the plurality of sensors each of the fingers to be detected is assigned, and uses an output of the sensor assigned to each of the fingers to be detected to identify and output a state of bending and stretching of the corresponding finger.