Robot system

A robot system comprising:

• a robot having a hand attaching/detaching mechanism at a distal end of a wrist thereof;
• a controller for controlling the robot;
• and
• a hand stand on which several types of hands to be voluntarily attached to the hand attaching/detaching mechanism of the robot are put and which includes a ground circuit that electrically grounds the hands put on the hand stand to the ground,
• wherein a first electrode to which detection voltage is applied is fixed to the distal end of the wrist of the robot,
• wherein each of the hands has a reference position to be a reference when the hand is attached to the hand attaching/detaching mechanism, and is provided with a second electrode so that distance from the reference position to the second electrode differs for each hand,
• wherein the robot system further comprises a current detecting unit for detecting electric current flowing into the ground circuit of the hand stand,
• wherein the controller includes:
• a hand selecting unit for selecting one of the hands;
• a storage unit that stores the types of the hands and positions of the second electrodes so that the types are associated with the positions, and a hand identifying unit that makes the robot operate to move the first electrode toward each one of the hands put on the hand stand and identifies whether or not the hand is a selected hand selected by the hand selecting unit on the basis of whether or not the electric current is detected by the current detecting unit when the first electrode has been moved to a position corresponding to the position of the second electrode of the selected hand.