An application to navigation system of modified invariant ekf

In this paper, the application of a modified IEKF (Invariant Extended Kalman Filter) to a navigation system is studied. Recently, a modification of IEKF was proposed by Seong [15] in order to consider various measurement equations, including nonlinear equations. In this paper, an aided navigation filter considering both linear and nonlinear measurement equations using the modified IEKF is presented. For nonlinear measurements such as speed and distance, the relationship between the invariant error and the measurement is derived, and from this, the linearized measurement matrix contributing to filter gain is then derived. Simulations and experiments were performed in order to verify the usefulness of the designed filter by comparison with conventional indirect feedback EKF. © 2020, Institute of Control, Robotics and Systems. All rights reserved.