467 research outputs found
Information Aided Navigation: A Review
The performance of inertial navigation systems is largely dependent on the
stable flow of external measurements and information to guarantee continuous
filter updates and bind the inertial solution drift. Platforms in different
operational environments may be prevented at some point from receiving external
measurements, thus exposing their navigation solution to drift. Over the years,
a wide variety of works have been proposed to overcome this shortcoming, by
exploiting knowledge of the system current conditions and turning it into an
applicable source of information to update the navigation filter. This paper
aims to provide an extensive survey of information aided navigation, broadly
classified into direct, indirect, and model aiding. Each approach is described
by the notable works that implemented its concept, use cases, relevant state
updates, and their corresponding measurement models. By matching the
appropriate constraint to a given scenario, one will be able to improve the
navigation solution accuracy, compensate for the lost information, and uncover
certain internal states, that would otherwise remain unobservable.Comment: 8 figures, 3 table
Synchronous-Clock, One-Way-Travel-Time Acoustic Navigation for Underwater Vehicles
This paper reports the development and deployment of a synchronous-clock acoustic navigation system suitable for the simultaneous navigation of multiple underwater vehicles. Our navigation system is composed of an acoustic modem–based communication and navigation system that allows for onboard navigational data to be broadcast as a data packet by a source node and for all passively receiving nodes to be able to decode the data packet to obtain a one-way-travel-time (OWTT) pseudo-range measurement and navigational ephemeris data. The navigation method reported herein uses a surface ship acting as a single moving reference beacon to a fleet of passively listening underwater vehicles. All vehicles within acoustic range are able to concurrently measure their slant range to the reference beacon using the OWTT measurement methodology and additionally receive transmission of reference beacon position using the modem data packet. The advantages of this type of navigation system are that it can (i) concurrently navigate multiple underwater vehicles within the vicinity of the surface ship and (ii) provide a bounded-error XY position measure that is commensurate with conventional moored long-baseline (LBL) navigation systems [i.e., ] but unlike LBL is not geographically restricted to a fixed-beacon network. We present results for two different field experiments using a two-node configuration consisting of a global positioning system–equipped surface ship acting as a global navigation aid to a Doppler-aided autonomous underwater vehicle. In each experiment, vehicle position was independently corroborated by other standard navigation means. Results for a maximum likelihood sensor fusion framework are reported.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/86046/1/reustice-2.pd
AN INTELLIGENT NAVIGATION SYSTEM FOR AN AUTONOMOUS UNDERWATER VEHICLE
The work in this thesis concerns with the development of a novel multisensor data fusion
(MSDF) technique, which combines synergistically Kalman filtering, fuzzy logic
and genetic algorithm approaches, aimed to enhance the accuracy of an autonomous
underwater vehicle (AUV) navigation system, formed by an integration of global positioning
system and inertial navigation system (GPS/INS).
The Kalman filter has been a popular method for integrating the data produced
by the GPS and INS to provide optimal estimates of AUVs position and attitude. In
this thesis, a sequential use of a linear Kalman filter and extended Kalman filter is
proposed. The former is used to fuse the data from a variety of INS sensors whose
output is used as an input to the later where integration with GPS data takes place.
The use of an adaptation scheme based on fuzzy logic approaches to cope with the
divergence problem caused by the insufficiently known a priori filter statistics is also
explored. The choice of fuzzy membership functions for the adaptation scheme is first
carried out using a heuristic approach. Single objective and multiobjective genetic
algorithm techniques are then used to optimize the parameters of the membership
functions with respect to a certain performance criteria in order to improve the overall
accuracy of the integrated navigation system. Results are presented that show
that the proposed algorithms can provide a significant improvement in the overall
navigation performance of an autonomous underwater vehicle navigation.
The proposed technique is known to be the first method used in relation to AUV
navigation technology and is thus considered as a major contribution thereof.J&S Marine Ltd.,
Qinetiq, Subsea 7 and South West Water PL
Recent Advances in Synchronous-Clock One-Way-Travel-Time Acoustic Navigation
This paper reports recent results in the development
and deployment of a synchronous-clock acoustic navigation
system suitable for the simultaneous navigation of multiple
underwater vehicles. The goal of this work is to enable the
task of navigating multiple autonomous underwater vehicles
(AUVs) over length scales of 0(100 km), while maintaining
error tolerances commensurate with conventional long-baseline
transponder-based navigation systems (0(1 m)), but without the
requisite need for deploying, calibrating, and recovering seafloor
anchored acoustic transponders. Our navigation system is comprised
of an acoustic modem-based communication/navigation
system that allows for onboard navigational data to be broadcast
as a data packet by a source node, and for all passively receiving
nodes to be able to decode the data packet to obtain a one-way
travel time pseudo-range measurement and ephemeris data. We
present field results for a two-node configuration consisting of a
surface ship acting as a global navigation aid to a Doppler-aided
AUV.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/86042/1/reustice-26.pd
Fusing Acoustic Ranges and Inertial Measurements in AUV Navigation: the Typhoon AUV at CommsNet13 Sea Trial
The paper presents some experimental results of autonomous underwater navigation, based on the fusion of acoustic and inertial measurements. The work is in the framework of the Thesaurus project, funded by the Tuscany Region, aiming at developing techniques for systematic exploration of marine areas of archaeological interest through a team of Autonomous Underwater Vehicles (AUVs). The test was carried out with one Typhoon vehicle, a 300m depth rated AUV with acoustic communication capabilities, during the CommsNet13 experiment, organized and scientifically coordinated by the NATO S&T Org. Ctr. for Maritime Research and Experimentation (CMRE, formerly NURC), with the participation of several research institutions. The fusion algorithm is formally casted into an optimal stochastic filtering problem, where the rough estimation of the vehicle position, velocity and attitude, are refined by using the depth measurement, the relative measurements available on the acoustic channel and the vehicle surge speed
Experimental Results in Synchronous-Clock One-Way-Travel-Time Acoustic Navigation for Autonomous Underwater Vehicles
This paper reports recent experimental results in the development and deployment of a synchronous-clock acoustic navigation system suitable for the simultaneous navigation of multiple underwater vehicles. The goal of this work is to enable the task of navigating multiple autonomous underwater vehicles (AUVs) over length scales of O(100 km), while maintaining error tolerances commensurate with conventional long-baseline transponder-based navigation systems (i.e., O(1 m)), but without the requisite need for deploying, calibrating, and recovering seafloor anchored acoustic transponders. Our navigation system is comprised of an acoustic modem-based communication/navigation system that allows for onboard navigational data to be broadcast as a data packet by a source node, and for all passively receiving nodes to be able to decode the data packet to obtain a one-way travel time pseudo-range measurement and ephemeris data. We present results for two different field experiments using a two-node configuration consisting of a global positioning system (GPS) equipped surface ship acting as a global navigation aid to a Doppler-aided AUV. In each experiment, vehicle position was independently corroborated by other standard navigation means. Initial results for a maximum-likelihood sensor fusion framework are reported.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/86032/1/reustice-20.pd
Towards autonomous localization and mapping of AUVs: a survey
Purpose The main purpose of this paper is to investigate two key elements of localization and mapping of Autonomous Underwater Vehicle (AUV), i.e. to overview various sensors and algorithms used for underwater localization and mapping, and to make suggestions for future research.
Design/methodology/approach The authors first review various sensors and algorithms used for AUVs in the terms of basic working principle, characters, their advantages and disadvantages. The statistical analysis is carried out by studying 35 AUV platforms according to the application circumstances of sensors and algorithms.
Findings As real-world applications have different requirements and specifications, it is necessary to select the most appropriate one by balancing various factors such as accuracy, cost, size, etc. Although highly accurate localization and mapping in an underwater environment is very difficult, more and more accurate and robust navigation solutions will be achieved with the development of both sensors and algorithms.
Research limitations/implications This paper provides an overview of the state of art underwater localisation and mapping algorithms and systems. No experiments are conducted for verification.
Practical implications The paper will give readers a clear guideline to find suitable underwater localisation and mapping algorithms and systems for their practical applications in hand.
Social implications There is a wide range of audiences who will benefit from reading this comprehensive survey of autonomous localisation and mapping of UAVs.
Originality/value The paper will provide useful information and suggestions to research students, engineers and scientists who work in the field of autonomous underwater vehicles
Cooperative Navigation for Low-bandwidth Mobile Acoustic Networks.
This thesis reports on the design and validation of estimation and planning algorithms for underwater vehicle cooperative localization. While attitude and depth are easily instrumented with bounded-error, autonomous underwater vehicles (AUVs) have no internal sensor that directly observes XY position. The global positioning system (GPS) and other radio-based navigation techniques are not available because of the strong attenuation of electromagnetic signals in seawater. The navigation algorithms presented herein fuse local body-frame rate and attitude measurements with range observations between vehicles within a decentralized architecture.
The acoustic communication channel is both unreliable and low bandwidth, precluding many state-of-the-art terrestrial cooperative navigation algorithms. We exploit the underlying structure of a post-process centralized estimator in order to derive two real-time decentralized estimation frameworks. First, the origin state method enables a client vehicle to exactly reproduce the corresponding centralized estimate within a server-to-client vehicle network. Second, a graph-based navigation framework produces an approximate reconstruction of the centralized estimate onboard each vehicle. Finally, we present a method to plan a locally optimal server path to localize a client vehicle along a desired nominal trajectory. The planning algorithm introduces a probabilistic channel model into prior Gaussian belief space planning frameworks.
In summary, cooperative localization reduces XY position error growth within underwater vehicle networks. Moreover, these methods remove the reliance on static beacon networks, which do not scale to large vehicle networks and limit the range of operations. Each proposed localization algorithm was validated in full-scale AUV field trials. The planning framework was evaluated through numerical simulation.PhDMechanical EngineeringUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/113428/1/jmwalls_1.pd
A parallel hypothesis method of autonomous underwater vehicle navigation
Submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy at the Massachusetts Institute of Technology and the Woods Hole Oceanographic Institution June 2009This research presents a parallel hypothesis method for autonomous underwater vehicle
navigation that enables a vehicle to expand the operating envelope of existing
long baseline acoustic navigation systems by incorporating information that is not
normally used. The parallel hypothesis method allows the in-situ identification of
acoustic multipath time-of-flight measurements between a vehicle and an external
transponder and uses them in real-time to augment the navigation algorithm during
periods when direct-path time-of-flight measurements are not available. A proof of
concept was conducted using real-world data obtained by the Woods Hole Oceanographic
Institution Deep Submergence Lab's Autonomous Benthic Explorer (ABE)
and Sentry autonomous underwater vehicles during operations on the Juan de Fuca
Ridge.
This algorithm uses a nested architecture to break the navigation solution down
into basic building blocks for each type of available external information. The algorithm
classifies external information as either line of position or gridded observations.
For any line of position observation, the algorithm generates a multi-modal block
of parallel position estimate hypotheses. The multimodal hypotheses are input into
an arbiter which produces a single unimodal output. If a priori maps of gridded
information are available, they are used within the arbiter structure to aid in the
elimination of false hypotheses. For the proof of concept, this research uses ranges
from a single external acoustic transponder in the hypothesis generation process and
grids of low-resolution bathymetric data from a ship-based multibeam sonar in the
arbitration process.
The major contributions of this research include the in-situ identification of acoustic
multipath time-of-flight measurements, the multiscale utilization of a priori low-resolution
bathymetric data in a high-resolution navigation algorithm, and the design
of a navigation algorithm with a
exible architecture. This flexible architecture allows
the incorporation of multimodal beliefs without requiring a complex mechanism for
real-time hypothesis generation and culling, and it allows the real-time incorporation
of multiple types of external information as they become available in situ into the
overall navigation solution
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