The invention provides a robot including a connection member relatively displaceably connected, and configured to control the displacement of the connection member based on a reference posture that can be adjusted, the robot including: a light emitting unit to emit a laser beam in a predetermined direction; a light receiving unit to receive the laser beam when the connection member is located in a detection posture that is away, by a preset displacement amount, from a predetermined zero posture; and a zeroing unit to relatively displace the connection member so as to make the light receiving unit receive the laser beam, and then to adjust the reference posture to the zero posture based on the posture of the connection member when the laser beam is received as well as on a relationship between the zero posture and the detection posture.