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Incorporation Of Carrier Phase Global Positioning System Measurements Into The Navigation Reference System For Improved Performance, Neil P. Hansen
Incorporation Of Carrier Phase Global Positioning System Measurements Into The Navigation Reference System For Improved Performance, Neil P. Hansen
Theses and Dissertations
In order to quantify the performance and accuracy of existing navigation systems, the U.S. Air Force has been using the Completely Integrated Reference Instrumentation System (CIRIS) as a baseline. CIRIS combines information from an inertial navigation unit, a barometric altimeter, and a range/range-rate system of ground transponders to obtain a navigation solution. This research explores the possibilities of enhancing CIRIS by adding measurements obtained from the Global Position System (GPS). Pure pseudorange measurement updates to the CIRIS Extended Kalman Filter form the basis of the Navigation Reference System (NRS). Applying differential corrections to the pseudorange measurements forms the basis of …
Failure Detection, Isolation, And Recovery In An Integrated Navigation System, William B. Mosle Iii
Failure Detection, Isolation, And Recovery In An Integrated Navigation System, William B. Mosle Iii
Theses and Dissertations
An Inertial Navigation System (INS), the Global Positioning System (GPS), and a ground based transponder system (RRS) can all be used to provide the user with a navigation solution. Yet by integrating these three navigation systems with an extended Kalman filter (EKF), a navigation solution is attained that benefits from the information of all three subsystems. This research develops a multiple model EKF failure detection, isolation, and recovery (FDIR) algorithm using a Chi-Square failure test to provide robust navigation solution to measurement failures. The algorithm specifically counters failures in the GPS and RRS range measurements. Analysis is conducted using a …
Enhanced Tracking Of Airborne Targets Using Forward Looking Infrared And Laser Return Measurements, Patrick J. Grondin
Enhanced Tracking Of Airborne Targets Using Forward Looking Infrared And Laser Return Measurements, Patrick J. Grondin
Theses and Dissertations
The Air Force Institute of Technology has been involved in developing Kalman filter based trackers of ballistic missiles for 15 years. The goal of this thesis is to develop a Multiple Model Adaptive Estimator MMAE that tracks the missile plume using a forward looking infrared sensor and the missile hardbody center-of-mass additionally using low energy laser returns for the purpose of directing a high power laser to incapacitate the missile. The missile plume pogos about an offset equilibrium point relative to the hardbody center-of-mass with an amplitude and frequency of oscillation that are not precisely known a priori. The MMAE …
Multiple Model Adaptive Estimation Applied To The Lambda Urv For Failure Detection And Identification, David W. Lane
Multiple Model Adaptive Estimation Applied To The Lambda Urv For Failure Detection And Identification, David W. Lane
Theses and Dissertations
Multiple Model Adaptive Estimation (MMAE) is a method of estimating unknown system parameters by modeling all possible parameter configurations in several models. The parameters for this research are failure status conditions associated with flight control actuators and sensors on the LAMBDA Unmanned Research Vehicle, an experimental aircraft operated by Wright Laboratory Flight Controls Division at Wright-Patterson Air Force Base, Ohio. Six actuator failures and eight sensor failures are modeled, along with the fully functional aircraft, in fifteen elemental Kalman filters. These filters propagate and update their own aircraft state estimates in real time. A probability computation representing the likelihood of …
Development Of A Performance Evaluation Tool (Mmsofe) For Detection Of Failures With Multiple Model Adaptive Estimation (Mmae), Robert L. Nielsen
Development Of A Performance Evaluation Tool (Mmsofe) For Detection Of Failures With Multiple Model Adaptive Estimation (Mmae), Robert L. Nielsen
Theses and Dissertations
Multiple model Kalman Filter (KF) techniques are used extensively for Multiple Model Adaptive Estimation (MMAE), Multiple Model Adaptive Control (MMAC), and Distributed Kalman Filter (DKF) applications to determine Bayesian- blended optimal estimates of states, uncertain parameters, and optimal control signals. Multiple model methods are used for sensor management, Failure Detection and Isolation (FDI), and other Guidance and Control (G and C) applications. A simulation tool called the Multiple Model Simulation for Optimal Filter Evaluation (MMSOFE) has been in this research. MMSOFE is based on the well-benchmarked single Kalman filter tool called Multimode Simulation for Optimal Filter Evaluation (MSOFE). MMSOFE is …
A New Approach To The Optimal Filtering Of Differential Phase Measurements Of Gps Signal In The Precision Survey, Shengan Wang
A New Approach To The Optimal Filtering Of Differential Phase Measurements Of Gps Signal In The Precision Survey, Shengan Wang
Dissertations and Theses
The Global Positioning System (GPS) has become popular research and application interests in surveying and many other areas. Nowadays, the accuracy of the Differential GPS can easily reach the order of a few meters. Yet, there are still many ways to exploit the GPS system signal carrier to improve the accuracy to less than meter level. In this thesis, a new approach to improve the accuracy to less than meter level is presented while the observer is in the dynamic situation. In order to reach the sub-meter accuracy, we measure on the carrier phase difference (The L1 carrier frequency is …
Application Of Sequence Comparison Methods To Multisensor Data Fusion And Target Recognition, Edmund W. Libby
Application Of Sequence Comparison Methods To Multisensor Data Fusion And Target Recognition, Edmund W. Libby
Theses and Dissertations
This research addresses methods for exploiting the joint likelihood of observed kinematic and nonkinematic (sensor signature) physical events to improve dynamic object and target recognition. A principal direction is the application of dynamic programming sequence comparison techniques to condition matching of object signatures to known models according to observed kinematics. A second direction is the application of kinematic/aspect-angle Kalman filter trackers to condition kinematic tracking according to observed signatures. These conditioning processes dramatically reduce ambiguity in object recognition, and can be used together or separately to allow computation of a posterior probabilities of object class membership using Bayesian methods. Proposals …
Comparison Of A Distributed Kalman Filter Versus A Centralized Kalman Filter With Fault Detection Considerations, Paul J. Lawrence Jr.
Comparison Of A Distributed Kalman Filter Versus A Centralized Kalman Filter With Fault Detection Considerations, Paul J. Lawrence Jr.
Theses and Dissertations
This project examined the results obtained by simulating an aircraft navigation system with a partial complement of a typical avionics sensor array. Two different techniques of estimation processes were utilized and compared: the conventional Kalman and the federated filter architectures. Areas of interest include error state estimation accuracy and overall performance, residual behavior under normal and induced sensor failure conditions, and potential for failure detection and isolation. Several simulations were accomplished for each filter design and the results were compared in order to verify the validity of the newly developed federated filter architecture. Comparison of the error state estimation accuracies …