In a method for controlling a posture of an articulated object, a user inputs an initial configuration of the object, a base point, an end point, a target point and a method for updating the posture. It is determined whether the number of joints positioned between the base and the end points is larger than or equal to three. If the number is smaller than or equal to two, it is determined whether the method for updating the posture is a two-segment or three-segment based method or another method for moving an intermediate end point. If the method is two-segment or three-segment based, the number is rechecked. If the number is smaller than or equal to two, the posture is modified according to the two-segment or three-segment based method. If the posture satisfies a predetermined condition, it is displayed on a screen.