PURPOSE: A movable robot system for mowing the grass and a method for controlling the same are provided to mowing the grass while avoiding obstacles within a grass existing area and to stop mowing by recognizing peoples or animals. CONSTITUTION: A movable robot system(1) for mowing the grass comprises a body, a first transceiving device(170), a boundary indicating device(20), and a controller(160). The body includes a moving device(120). The first transceiving device is included in the body and transceives condition information consulting signals. One or more boundary indicating devices are arranged in a grass existing area and include a second transceiving device which receives condition information consulting signals from the first transceiving device and transmits condition information confirmation signals to the first transceiving device. The control unit recognizes an absolute coordinate within the grass existing area based on the condition information confirmation signals. [Reference numerals] (10,20) Movable robot for mowing the grass； (120) Moving device； (130) Power supply device； (140) Mowing device； (150) Detecting device； (151) Infrared sensor； (153) Ultrasonic sensor； (160) Controller； (161) Memory； (170) First transceiving device； (210) Infrared ray irradiating unit； (220) Lamp unit； (230) Photovoltaic cell； (240) Second transceiving device본 발명의 일 실시예에 따른 잔디 깎기용 이동로봇 시스템은 이동장치가 구비된 본체와, 본체에 구비되고 상태정보 문의신호를 송수신하는 제1송수신장치와, 잔디존재영역에 적어도 하나 이상 배치되며 제1송수신장치로부터 상태정보 문의신호를 수신하고 제1송수신장치에 상태정보 확인신호를 송신하는 제2송수신장치가 구비되는 경계표시장치 및, 제2송수신장치에서 수신된 상태정보 확인신호에 의해 잔디존재영역 내에서 절대좌표를 인식하는 제어부를 포함한다.
