Posture computing apparatus for work machine, work machine, and posture computation method for work machine

A posture computing apparatus for a work machine, to obtain a posture angle of the work machine including a traveling body and a swing body that is mounted on the traveling body and that rotates relative to the traveling body, the posture computing apparatus comprising:

• a detection apparatus that detects angular velocity and acceleration of the work machine, the detection apparatus being provided to the swing body;
• an acceleration correcting unit that corrects the acceleration detected by the detection apparatus to an acceleration to be detected when the detection apparatus is placed on a center of the swing body, by subtracting components of acceleration acting on the detection apparatus including a centrifugal acceleration which is determined from centrifugal force from the acceleration detected by the detection apparatus based on a position where the detection apparatus is placed in the swing body with respect to the center of the swing body and the angular velocity and acceleration detected by the detection apparatus;
• and
• a posture angle computing unit that obtains a posture angle of the work machine from the acceleration corrected by the acceleration correcting unit and the angular velocity detected by the detection apparatus.