PURPOSE: To easily set a relative position between a robot and a work, by providing a moving mechanism and a turning mechanism in a hand mounted to a robot arm and moving the robot hand with contactors of these mechanisms hitting a work.

CONSTITUTION: The method, moving a robot arm 3 in the direction of an arrow head G in the drawing, moves both end contactors 35a, provided in both sides of a turning mechanism 10, so as to hit a front part 35a of a tested device 32 for a tested device 34 conveyed being mounted to a pallet 5. Then the turning mechanism 10 is turned against urging force of a tension spring, and the contactor 35a is adapted to the front part 35a of the tested device 32. Next the method, lowering a robot hand 3, moves a contactor 35b, provided in the right end part of a turning plate member 28, to hit an upper part 34b of the tested device 34. Further the method, moving the robot hand 3, actuates a contactor 35c to hit an internal wall surface 34c. In this way, a robot hand 8 can be positioned in a predetermined position of the tested device 34.