Download or read book Design and Evaluation of an Integrated GPS INS System for Shallow water AUV Navigation written by Eric R. Bachmann and published by . This book was released on 1995 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The major problem addressed by this research is the large and/or expensive equipment required by a conventional navigation system to accurately determine the position of an Autonomous Underwater Vehicle (AUV) during all phases of an underwater search or mapping mission. The approach taken was to prototype an integrated navigation system which combines Global Positioning System (OPS) and Inertial Measurement Unit (IMU), waterspeed and heading information using Kalman filtering techniques. Actual implementation was preceded by a computer simulation to test where the unit would fit into a larger hardware and software hierarchy of an AUV. The system was then evaluated in experiments which began with land based cart tests and progressed to open water trials where the unit was placed in a towed body behind a boat and alternately submerged and surfaced to provide periodic OPS updates to the Inertial Navigation System (INS). Test results and qualitative error estimates indicate that submerged navigation accuracy comparable to that of differential OPS may be attainable for periods of 30 seconds or more with low cost components of a small physical size.

Download or read book Design and Evaluation of an Integrated GPS INS System for Shallow water AUV Navigation written by Eric R. Bachmann and published by . This book was released on 1995 with total page 222 pages. Available in PDF, EPUB and Kindle. Book excerpt: The major problem addressed by this research is the large and/or expensive equipment required by a conventional navigation system to accurately determine the position of an Autonomous Underwater Vehicle (AUV) during all phases of an underwater search or mapping mission. The approach taken was to prototype an integrated navigation system which combines Global Positioning System (OPS) and Inertial Measurement Unit (IMU), waterspeed and heading information using Kalman filtering techniques. Actual implementation was preceded by a computer simulation to test where the unit would fit into a larger hardware and software hierarchy of an AUV. The system was then evaluated in experiments which began with land based cart tests and progressed to open water trials where the unit was placed in a towed body behind a boat and alternately submerged and surfaced to provide periodic OPS updates to the Inertial Navigation System (INS). Test results and qualitative error estimates indicate that submerged navigation accuracy comparable to that of differential OPS may be attainable for periods of 30 seconds or more with low cost components of a small physical size.

Download or read book Design and Evaluation of an Integrated Self contained GPS INS Shallow water Navigation AUV Navigation System SANS written by Randy G. Walker and published by . This book was released on 1996 with total page 157 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Design and Evaluation of an Integrated Self Contained GPS INS Shallow Water AUV Navigation System SANS written by Randy G. Walker and published by . This book was released on 1996-06-01 with total page 180 pages. Available in PDF, EPUB and Kindle. Book excerpt: The main problem addressed by this research is to find an alternative to the use of large and/or expensive equipment required by conventional navigation systems to accurately determine the position of an Autonomous Underwater Vehicle (AUV) during all phases of an underwater search or mapping mission. The approach taken was to advance an existing integrated navigation system prototype which combines Global Positioning System (GPS), Inertial Measurement Unit (IMU), water speed, and heading information using Kalman filtering techniques. The hardware and software architecture of the prototype system were advanced to a level such that it is completely self- contained in a relatively small, lightweight package capable of on-board processing of sensor data and outpouring updated position fixes at a rate of 10 Hz; an improvement from the 5 Hz rate delivered by the prototype. The major changes to the preceding prototype implemented by this research were to install an on-board processor to locally process sensor outputs, and improve upon the analog filter and voltage regulation circuitry. Preliminary test results indicate the newly designed SANS provides a 100% performance improvement over the previous prototype. It now delivers a 10Hz update rate, and increased accuracy due to the improved analog filter and the higher sampling rate provided by the processor.

Download or read book 2484 written by and published by . This book was released on 1941 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Analysis Experimental Evaluation and Software Upgrade for Attitude Estimation by the Shallow Water AUV Navigation System SANS written by Ricky L. Roberts and published by . This book was released on 1997-03-01 with total page 209 pages. Available in PDF, EPUB and Kindle. Book excerpt: The main problem addressed by this research is the lack of a small, low-cost integrated navigation system to accurately determine the position of an Autonomous Underwater Vehicle (AUV) during all phases of an underwater search or mapping mission. The approach taken utilized an evolving prototype, called the Shallow-Water AUV Navigation System (SANS), combining Global Positioning System (GPS), Inertial Measurement Unit (IMU), water speed, and magnetic heading information using Kalman, low-pass, and complimentary filtering techniques. In previous work, addition of a math coprocessor improved system update rate from 7 to 18 Hz, but revealed input/output coordination weaknesses in the software. The central focus of this thesis is on testing and programming improvements which resulted in reliable integrated operations and an increased processing speed of 40 Hz. This now allows the filter to perform in real time. A standardized tilt table evaluation and calibration procedure for the navigation filter also was developed. The system was evaluated in dynamic tilt table experiments. Test results and qualitative error estimates using differential GPS suggest that submerged navigation with SANS for a period of several minutes will result in position estimation errors typically on the order of 10 meters rms, even in the presence of substantial ocean currents.

Download or read book Evaluation of Hardware and Software for a Small Autonomous Underwater Vehicle Navigation System SANS written by Nancy Ann Norton and published by . This book was released on 1994 with total page 142 pages. Available in PDF, EPUB and Kindle. Book excerpt: The purpose of this thesis is to evaluate the hardware and software for a Small Autonomous Underwater Vehicle (AUV) Navigation System (SANS), a self-contained, externally mountable navigation system. The SANS is designed to determine the location of an underwater object using a combination of Global Positioning System (GPS) while surfaced, sand Inertial Navigation System (INS) while submerged. Various experimental testing of the hardware was performed to determine the ability of the GPS navigation system to function within the mission requirements. A test was done to determine the time required to obtain a GPS fix. A test of the system while the antenna was covered with water, was done to determine if the GPS signal could penetrate a shallow while the antenna was covered with water, was done to determine if the GPS signal could penetrate a shallow layer of water. Finally, a sea test was done to determine the feasibility of reacquiring a GPS fix after the system has been submerged during normal ocean wave wash. A computer simulation was written in Common LISP Object System (CLOS) in order to evaluate the errors introduced by using a accelerometer in the INS to determine the climb angle of the AUV while surfacing. The experimental testing of the GPS system showed that the GPS signal is able to penetrate a shallow layer of water covering the antenna, and that the system is able to meet the accuracy and time requirements of the mission while being splashed by wave wash. The simulation results show that the error introduced by measuring climb angle with an accelerometer is minor and will not significantly degrade the accuracy of the system.

Download or read book Technology Survey and Preliminary Design for Small AUV Navigation System written by Robert B. McGhee and published by . This book was released on 1992 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Navigation of an Autonomous Underwater Vehicle (AUV) is a problem that has not been adequately solved. Although the inclusion of the Global Positioning System (GPS) into AUV navigation has been briefly examined before, this possibility is explored further in this report. GPS and Inertial Measurement System (INS) based navigation package offers many advantages for AUV navigation especially for transit and precise object location in shallow water. This report provides background information on GPS and INS as they pertain to small AUV employment. Other required components are also examined as they pertain to small AUV employment. The use of the GPS/INS navigation package for AUV transits and precise object location work is presented. Two preliminary Small AUV Navigation System (SANS) designs with specified components are developed. GPS, INS, IMV, Navigation, AUV missions Computer System Hardware, Real-Time Software.

Download or read book Compilation of Theses Abstracts October 1994 September 1995 written by United States. Naval Postgraduate School, Monterey, CA. and published by . This book was released on 1995 with total page 564 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Incorporation of GPS INS Into Small Autonomous Underwater Vehicle Navigation written by and published by . This book was released on 1992 with total page 60 pages. Available in PDF, EPUB and Kindle. Book excerpt: Navigation of an Autonomous Underwater Vehicle (AUV) is a problem that has not been adequately solved. Although the inclusion of the Global Positioning System (GPS) into AUV navigation has been briefly examined before, this possibility is explored further in this thesis. GPS and Inertial Measurement System (INS) based navigation package offers many advantages for AUV navigation especially for transits and precise object location in shallow water. This thesis provides background information on GPS and INS as they pertain to small AUV employment. Other required components are also examined as they pertain to small AUV employment. The use of the GPS/INS navigation package for AUV transits and precise object location work is presented. Two designs with specified components are developed. A GPS receiver was tested for AUV employment suitability. These test results are presented and analyzed. Autonomous underwater vehicles, Global positioning system, Inertial measurement system.

Download or read book A Summary of Research 1995 written by United States. Naval Postgraduate School, Monterey, CA. and published by . This book was released on 1995 with total page 588 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Proceedings of the 9th International Symposium on Unmanned Untethered Submersible Technology September 27 29 1995 written by and published by . This book was released on 1995 with total page 506 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Simulation Based Validation of Navigation Filter Software for a Shallow Water AUV Navigation System SANS written by Ruediger Steven and published by . This book was released on 1996-03-01 with total page 145 pages. Available in PDF, EPUB and Kindle. Book excerpt: Navigation filter software is currently being developed for an inertial navigation system without rotating gyros. This system shall replace the navigation system that is currently used in the Phoenix Autonomous Underwater Vehicle of the Naval Postgraduate School. The filter combines acceleration sensors, angular rate sensors, a water speed sensor, a magnetic compass and a GPS system. The harmonization of the sensors is performed by gain matrices. The filter code must be tested for correctness and evaluated, and optimal values for the gain matrices must be found. Both factors directly influence the accuracy of the computed positions, and thus the quality of AUV navigation. in this thesis, the Kalman filter code is tested by experimentation with a simulation of a submarine. Two versions of the code are available, both written in LISP and C++. Test runs are performed in different simulated sea-states (water current), with and without noise added to the sensors, and with different values for the gain matrices. Based on the experiments, the Kalman filter code seems to be correct and stable. Noise is the most important determinant of the filter performance. The results can be optimized by careful fine tuning of the gain matrices.

Download or read book Global Navigation Satellite Systems Inertial Navigation and Integration written by Mohinder S. Grewal and published by John Wiley & Sons. This book was released on 2020-01-22 with total page 610 pages. Available in PDF, EPUB and Kindle. Book excerpt: Covers significant changes in GPS/INS technology, and includes new material on GPS, GNSSs including GPS, Glonass, Galileo, BeiDou, QZSS, and IRNSS/NAViC, and MATLAB programs on square root information filtering (SRIF) This book provides readers with solutions to real-world problems associated with global navigation satellite systems, inertial navigation, and integration. It presents readers with numerous detailed examples and practice problems, including GNSS-aided INS, modeling of gyros and accelerometers, and SBAS and GBAS. This revised fourth edition adds new material on GPS III and RAIM. It also provides updated information on low cost sensors such as MEMS, as well as GLONASS, Galileo, BeiDou, QZSS, and IRNSS/NAViC, and QZSS. Revisions also include added material on the more numerically stable square-root information filter (SRIF) with MATLAB programs and examples from GNSS system state filters such as ensemble time filter with square-root covariance filter (SRCF) of Bierman and Thornton and SigmaRho filter. Global Navigation Satellite Systems, Inertial Navigation, and Integration, 4th Edition provides: Updates on the significant upgrades in existing GNSS systems, and on other systems currently under advanced development Expanded coverage of basic principles of antenna design, and practical antenna design solutions More information on basic principles of receiver design, and an update of the foundations for code and carrier acquisition and tracking within a GNSS receiver Examples demonstrating independence of Kalman filtering from probability density functions of error sources beyond their means and covariances New coverage of inertial navigation to cover recent technology developments and the mathematical models and methods used in its implementation Wider coverage of GNSS/INS integration, including derivation of a unified GNSS/INS integration model, its MATLAB implementations, and performance evaluation under simulated dynamic conditions Global Navigation Satellite Systems, Inertial Navigation, and Integration, Fourth Edition is intended for people who need a working knowledge of Global Navigation Satellite Systems (GNSS), Inertial Navigation Systems (INS), and the Kalman filtering models and methods used in their integration.

Download or read book Global Positioning Systems Inertial Navigation and Integration written by Mohinder S. Grewal and published by John Wiley & Sons. This book was released on 2004-04-05 with total page 415 pages. Available in PDF, EPUB and Kindle. Book excerpt: The only comprehensive guide to Kalman filtering and its applications to real-world GPS/INS problems Written by recognized authorities in the field, this book provides engineers, computer scientists, and others with a working familiarity with the theory and contemporary applications of Global Positioning Systems (GPS), Inertial Navigational Systems, and Kalman filters. Throughout, the focus is on solving real-world problems, with an emphasis on the effective use of state-of-the-art integration techniques for those systems, especially the application of Kalman filtering. To that end, the authors explore the various subtleties, common failures, and inherent limitations of the theory as it applies to real-world situations, and provide numerous detailed application examples and practice problems, including GPS-aided INS, modeling of gyros and accelerometers, and WAAS and LAAS. Drawing upon their many years of experience with GPS, INS, and the Kalman filter, the authors present numerous design and implementation techniques not found in other professional references, including original techniques for: * Representing the problem in a mathematical model * Analyzing the performance of the GPS sensor as a function of model parameters * Implementing the mechanization equations in numerically stable algorithms * Assessing computation requirements * Testing the validity of results * Monitoring GPS, INS, and Kalman filter performance in operation In order to enhance comprehension of the subjects covered, the authors have included software in MATLAB, demonstrating the workings of the GPS, INS, and filter algorithms. In addition to showing the Kalman filter in action, the software also demonstrates various practical aspects of finite word length arithmetic and the need for alternative algorithms to preserve result accuracy.

Download or read book An Integrated INS GPS Navigation System for Small AUVs Using an Asynchronous Kalman Filer written by Glenn C. Hernandez and published by . This book was released on 1998 with total page 41 pages. Available in PDF, EPUB and Kindle. Book excerpt: A Small AUV Navigation System (SANS) is being developed at the Naval Postgraduate School. The SANS is an integrated INS/GPS navigation system composed of low-cost, small-size components. It is designed to demonstrate the feasibility of using a low-cost Inertial Measurement Unit (IMU) to navigate between intermittent GPS fixes. This thesis presents recent improvements to the SANS hardware and software. The 486-based ESP computer used in the previous version of SANS is now replaced by an AMD 586DX133 based PC/104 computer to provide more computing power, reliability and compatibility with PC/104 industrial standards. The previous SANS navigation filter consisting of a complementary constant gain filter is now aided by an asynchronous Kalman filter. This navigation filter has six states for orientation estimation (constant gain) and eight states for position estimation (Kalman filtered). Low- frequency DGPS noise is explicitly modeled based on an experimentally obtained autocorrelation function. Ocean currents are also modeled as a low-frequency random process. The asynchronous nature of GPS measurements resulting from AUV submergence or wave splash on the DGPS antennas is also taken into account by adopting an asynchronous Kalman filter as the basis for the SANS software. Matlab simulation studies of the asynchronous filter have been conducted and results documented in this thesis.

Download or read book An Integrated INS GPS Navigation System for Small AUVS Using an Asynchronous Kalman Filter written by Glenn C. Hernandez and published by . This book was released on 1998 with total page 56 pages. Available in PDF, EPUB and Kindle. Book excerpt: A Small AUV Navigation System (SANS) is being developed at the Naval Postgraduate School. The SANS is an integrated INS/GPS navigation system composed of low-cost, small-size components. It is designed to demonstrate the feasibility of using a low-cost Inertial Measurement Unit (IMU) to navigate between intermittent GPS fixes. This thesis presents recent improvements to the SANS hardware and software. The 486-based ESP computer used in the previous version of SANS is now replaced by an AMD 586DX133 based PC/104 computer to provide more computing power, reliability and compatibility with PC/104 industrial standards. The previous SANS navigation filter consisting of a complementary constant gain filter is now aided by an asynchronous Kalman filter. This navigation filter has six states for orientation estimation (constant gain) and eight states for position estimation (Kalman filtered). Low-frequency DGPS noise is explicitly modeled based on an experimentally obtained a autocorrelation function. Ocean currents are also modeled as a low-frequency random process. The asynchronous nature of GPS measurements resulting from AUV submergence or wave splash on the DGPS antennas is also taken into account by adopting an asynchronous Kalman filter as the basis for the SANS software. Matlab simulation studies of the asynchronous filter have been conducted and results documented in this thesis.