(EN)
To accurately calculate an attached angle of an accelerometer and accurately correct an acceleration that is obtained from the accelerometer: a frequency analyzing module of an acceleration corrector divides a sensor coordinate system acceleration into a bias frequency component, a gravity frequency component, a movement acceleration frequency component, and a noise frequency component, through a wavelet transform. The frequency analyzing module outputs a sum component of the gravity frequency component and the movement acceleration frequency component to an attached angle estimating module and a correcting operation module. The attached angle estimating module estimation-calculates the attached angle of an accelerometer and outputs it to the correcting operation module. The correcting operation module corrects the acceleration, which is including of the sum component of the gravity frequency component and the movement acceleration frequency component, based on the estimation-calculated attached angle to calculate a movable body coordinate system acceleration.