CTU Events

Nonlinear Observer Design for Strapdown Inertial Navigation Systems

12 May 2016   10:00-11:30

Since 1960 the Kalman filter (KF), and nonlinear extensions thereof, has been used to provide integrated navigation solutions based on different types of measurements. One disadvantage of the KF is its relatively high computational complexity, with the number of internal states growing quadratically with the number of actual estimates. Another disadvantage is that the KF is developed for linear systems and stability can be difficult or impossible to prove for nonlinear extensions such as the extended Kalman filter (EKF). Consequently, there is a growing interest in the design of nonlinear observers for strapdown inertial navigation systems (INS), which can provide explicit stability guarantees and reduced computational complexity.

In this talk, globally exponentially stable (GES) observers for attitude and the translational motion is presented for strapdown INS. The attitude observer avoids the well-known topological obstructions to global stability by not confining the attitude estimate to SO(3), but rather estimating a full rotation matrix with nine degrees of freedom. A quaternion-based representation for effective implementation, which guarantees semiglobal exponential stability, is also presented. Next, a translational motion observer (TMO) for estimation of position and linear velocity is presented. Explicit stability requirements for GES are given for the feedback interconnection. The presentation focuses on the theory of nonlinear observers, stability properties and experimental validation of the methods.



Biosketch: Thor I. Fossen received an MSc degree in Marine Technology in 1987 and a PhD degree in Engineering Cybernetics in 1991 both from the Norwegian University of Science and Technology (NTNU), Trondheim. He is currently professor of guidance, navigation and control and co-director of the NTNU Centre for Autonomous Marine Operations and Systems. Fossen?s expertise covers guidance, inertial navigation systems, nonlinear control and observer theory, vehicle dynamics, hydrodynamics, autopilots and unmanned vehicles. He has been elected to the Norwegian Academy of Technological Sciences and elevated to IEEE Fellow.

Place

T2:A3-318

Organizer

katedra měření, FEL

Contact person

doc. Ing. Jan Roháč, Ph.D., xrohac@fel.cvut.cz

More information

http://measure.feld.cvut.cz/node/3683