Fecha de publicación: 11/06/1998 Fuente: WIPO "royal booby" A controller of a construction machine such as a hydraulic shovel which digs the ground has an angle detecting means (20-22) for detecting the posture of an articulated arm mechanism in terms of angle information, a converting means (26) which converts the detected angle information into expansion/contraction displacement information of a corresponding cylinder actuator (120-122) and a control means (1) which controls the actuator (120-122) to have the required expansion/contraction displacement in accordance with the obtained expansion/contraction displacement information. Thus the position and posture of a working member (400) can be accurately and stably controlled while the cost is kept low.