Terrain-Aided Navigation With Coarse Maps—Toward an Arctic Crossing With an AUV

Abstract

The desire to conduct research in the Arctic on an ever-larger spatio-temporal scales has led to the development of long-range autonomous underwater vehicles (AUVs), such as the Autosub Long-Range 1500 (ALR1500). Whilst these platforms open up a world of new applications, their actual use is limited in GPS-denied environments since self-contained navigation remains yet unavailable. In response, this study evaluates whether terrain-aided navigation (TAN) can enable multi-month deployments using basic navigation sensors and sparse bathymetric maps. To evaluate the potential, ALR1500 undertakes a hypothetical science-driven mission from Svalbard (Norway) to Point Barrow (Alaska, USA) under the sea ice (a mission over 3200 km). Therefore, a simulated environment is developed which integrates a state-of-the-art model of water circulation, error models for heading estimation at high latitudes and an Arctic bathymetric map. Recognising that this map is constructed based on sparse depth measurements and interpolation techniques, a bathymetric uncertainty model is developed. The performance of the TAN algorithm is examined with respect to the type of the heading sensor utilised and a range of vertical map distortions, calculated using the developed bathymetric uncertainty model. Simulations show that unaided navigation experiences an error of hundreds of kilometres, whereas TAN provides acceptable accuracy given a moderate map distortion. By degrading the quality of the map further, it appears that the navigation filter may diverge when traversing large regions subject to interpolation. Therefore, a Rapidly-exploring Random Tree Star (RRT * ) algorithm is used to design a new path such that the AUV traverses reliable and rich in topographic information areas.

Underwater terrain positioning method based on Markov random field for unmanned underwater vehicles

“…Owing to the poor energy reserves of UUVs, CTFMs based on MBES are not suitable for engineering applications unless the battery field has a major technological breakthrough (Ma et al, 2020). Thus, CTFMs typically use lowpower sensors, such as the Doppler velocity log (DVL) and acoustic altimeter, for water depth measurements (Salavasidis et al, 2021;Jiang et al, 2022). Compared with CTFMs, UTPMs were developed using TERCOM, which only requires multiple terrain-measured profiles (ping), which is relatively more advantageous.…”

A Novel Multi-Hypothesis Filter for Terrain Aided Navigation

“…Turan and Kutay test the performance of two different PF resampling methods in TAN [18]. Rao-Blackwellized implementations of PF, in which the linear and non-linear parts of the state vector are separated, have been extensively utilized in recent studies related to Terrain-Aided Navigation for underwater vehicles [19], [20], [21]. Rupeng et al proposes a terrain aided positioning (TAP) confidence interval model for PF to mitigate the initial TAN positioning error [22].…”

In-situ characterization of sea state with improved navigation on an Autonomous Underwater Glider

“…as capable platforms for making in-situ measurements for a variety of ocean processes [11]. With some exceptions, AUVs generally do not possess the endurance for long-range missions and often require a support vessel for transit to test sites [12,13,14]. AUVs that do possess the range for trans-oceanic missions tend to take a "scaling-up" approach, opting for high volume displacement and high power budgets, ultimately increasing cost and decreasing operational flexibility.…”

“…Gliders are commonly used to sample the water column for conductivity, temperature and other chemical properties. Expanding upon these sensing capabilities to allow an AUG to not only take measurements of the water column but also to estimate ocean currents (Chapter 3), characterize surface wave parameters (Chapter 4), identify bathymetric features [13,23], and identify sea-ice characteristics [24] are critical to an AUG's overall utility.…”

“…Geophysical navigation methods use onboard sensing to extract environmental features which are then compared to an a priori map. One of the most common forms of geophysical navigation used on AUVs is terrain-aided navigation (TAN) [13,23,50]. Bathymetric features used in TAN can be extracted using acoustic sensors onboard an AUV.…”