Robot system

A robot system comprising:

• a robot including a hand that holds a workpiece, and a wrist capable of rotating the hand around a rotation axis in a substantially vertical direction;
• and
• a control unit that controls the robot so as to rotate the wrist to pick up the workpiece by the hand,
• wherein the control unit comprises a processor configured to:
• detect a phase of the workpiece around an axis in the substantially vertical direction;
• acquire a current phase of the hand based on a current rotation angle of the wrist;
• select, based on the acquired current phase of the hand and the detected phase of the workpiece, any one of a plurality of reference phases previously set for a relative phase of the hand with respect to the phase of the workpiece;
• and
• control the robot so as to rotate the wrist until the relative phase becomes the selected reference phase to pick up the workpiece by the hand.