Controller and control method

A controller for a punching device configured to sequentially punch a long sheet base material into a predetermined shape while feeding the sheet base material in a longitudinal direction of the sheet base material,

• wherein a plurality of reserved-for-punching areas that are to be punched by the punching device are set in advance on the sheet base material so as to be arranged in the longitudinal direction at a predetermined interval,
• the controller comprising one or more processors, wherein the one or more processors execute computer-executable instructions stored in a memory to cause the controller to:
• acquire image information on the sheet base material from an imaging device configured to image the sheet base material;
• determine, based on the image information, whether a specific reserved-for-punching area is present, which is a reserved-for-punching area that overlaps at least one defective site included in the sheet base material;
• and
• in a case where the specific reserved-for-punching area is present, shift the reserved-for-punching area determined to be the specific reserved-for-punching area upstream in a feeding path for the sheet base material with respect to the defective site.