Workpiece identification method

A workpiece identification method including capturing an image of a workpiece storage area in which a plurality of workpieces is to be placed, the workpieces each including a soft body portion having a free line shape,

• determining whether or not the workpieces are present in the workpiece storage area based on the image acquired by the image capturing,
• when the workpieces are determined to be present, determining, based on the image, whether or not a crossing part is present in the workpiece storage area, the crossing part being a part where the soft body portions of a plurality of workpieces cross each other in an overlapping manner,
• when the crossing part is determined to be present, determining, based on the image, an uppermost soft body portion placed at an uppermost position among the soft body portions crossing each other, and
• determining that a workpiece including the uppermost soft body portion thus determined is an uppermost workpiece placed at an uppermost position,
• the workpiece identification method comprising:
• when the uppermost soft body portion is not determinable based on the image, considering a procedure for creating the uppermost soft body portion by moving one or more workpieces;
• and
• moving the one or more workpieces in accordance with the procedure found by the consideration so that the uppermost soft body portion is created.