A work implement includes a breaker. Sensors detect an attitude of the work implement. A pilot valve controls the operation of the breaker. A controller controls the pilot valve. The controller detects, from the attitude of the work implement obtained by the sensors, a distance between a tip of the breaker and a striking limit. When it is determined that the tip of the breaker has reached the striking limit, the controller controls the pilot valve to stop the operation of the breaker.