Abstract:

Aiming at the problem of larger calculation burden of the quaternion unscented Kalman filter (USQUE), a modified USQUE (MUSQUE) is proposed. Based on the transformation between the quaternion and the modified rodriguez parameter (MRP), the novel method can reduce calculation amount by avoiding frequent transformation between the quaternion and the error-MRP for the USQUE. Meanwhile, the singularity avoidance method is also derived in case when the MRP is singularity. By simulating strapdown inertial navigation system/global positioning system (SINS/GPS) direct integrated navigation, the results prove the validation of the novel method comparing with the multiplicative extended Kalman filter and USQUE.