| 摘要 |
PROBLEM TO BE SOLVED: To reduce error in the estimated value of fixing error caused by distortion of hull by weighting an estimated angular speed obtained through an inertial navigation system and a main inertial navigation system mounted on a sailing body and setting the angular speed difference of error covariance of the observation disturbance vector of a Kalman filter larger than a standard value. SOLUTION: At the time of estimating a fixing error around Z axis through an inertial navigation system, an angular speed estimated based on X angular speed difference is weighted as compared with that based on Y angular speed difference obtained through a master INS 10 and a sailing body INS 20. X and Y angular speed differences of a matrix RE satisfy a relationship; RE (X angular speed) <RE (Y angular speed difference). At the time of estimating a fixing error through a Kalman filter, a plurality of parameters are selected and weighted as observation values. Extent of weighting of estimation is distributed to minimize the error caused by distortion of hull contained in the fixing error. Extent of each state vector is represented by Kalman gain from observation values. Subsequently, initial value of error covariance matrix, covariance matrix of system disturbance vector error, and the like, are set. |
