Towards Model-Aided Navigation of Underwater Vehicles

Abstract

This paper reports the development and preliminary experimental evaluation of a model-aided inertial navigation system (INS) for underwater vehicles. The implemented navigation system exploits accurate knowledge of the vehicle dynamics through an experimentally validated mathematical model, relating the water-relative velocity of the vehicle to the forces and moments acting upon it. Together with online current estimation, the model output is integrated in the navigation system. The proposed approach is of practical interest both for underwater navigation when lacking disparate velocity measurements, typically from a Doppler velocity log (DVL), and for systems where the need for redundancy and integrity is important, e.g. during sensor dropouts or failures, or in case of emergency navigation. The presented results verify the concept that with merely an addition of software and no added instrumentation, it is possible to considerably improve the accuracy and robustness of an INS by utilizing the output from a kinetic vehicle model. To the best of our knowledge, this paper is the first report on the implementation and experimental evaluation of model-aided INS for underwater vehicle navigation.

Model-Aided Navigation with Sea Current Estimation for an Autonomous Underwater Vehicle

“…In this work, we follow the idea and concept of using the dynamic vehicle model for aiding an INS [14,15]. The use of a vehicle DM as a source of information to aid the solution of the inertial navigator has the benefit of not requiring any additional hardware and the potential of being self-contained.…”

“…Developed for supervision and exploration tasks, the design resembles the general structure of several well-known AUVs, such as HUGIN 4500 [14], REMUS [20] and STARFISH [21], but at a different scale and with changes in the governing organs. With steel built in, this low-speed "cigar-shaped" vehicle is completely symmetrical in the x-z plane, with good symmetry in the y-z plane and quasi-symmetric in the x-y plane, as shown in Figure 1.…”

“…In this work, we follow the recent developments of MA-INSs for underwater vehicles based on a three-DOF non-linear model [14,15] and propose a modelaided inertial navigation strategy based on the linear three-DOF DM for the HRC-AUV (a low-cost AUV under development by the Cuban Hydrographic Research Center (HRC) and the Group of Automation, Robotics and Perception (GARP) [16,17,18,19]). The proposed strategy, within a KF framework, also estimates in real-time the magnitude of the main environmental perturbation, i.e., the sea current.…”

Making AUVs Truly Autonomous

“…The sea current will often constitute the dominant error source when aiding the INS with water-relative velocity data, in particular when applying DVL water track data. For additional information on model-aiding and sea current estimation, the reader may refer to (Hegrenaes et al, 2007) and .…”

A Novel Hybrid Approach to Deal with DVL Malfunctions for Underwater Integrated Navigation Systems

“…Therefore, in order to improve the navigation performance, it is necessary to introduce auxiliary sensors to limit the error growth of the SINS. Now the integrated navigation system which consists of multiple navigation sensors is widely adopted on underwater vehicles [6][7][8]. As a high-precision velocity measuring instrument, the Doppler velocity log (DVL) has become increasingly popular as the fundamental component of underwater integrated navigation systems [9][10][11][12][13].…”