Engineering Commons^™

Modeling Aircraft Disturbance Fields For Magnetic Navigation Using Dense Anns And The Novel Manntl Architecture, Kyle A. Emery

Theses and Dissertations

The ability to use GPS for navigation is becoming increasingly limited in certain areas of the world. Knowing this, the Air Force Research Labs is constantly looking for ways to improve alternate navigation methods such as magnetic navigation. In the interest of making advancements in aircraft disturbance field modelling, Lieutenant Emery recreates models from previous works to prove results. Lieutenant Emery also introduces a novel model architecture that attempts to mix the filtering properties of Tolles-Lawson with the non-linear capabilities of an artificial neural network. The introduction of this model could present better aircraft disturbance field modelling and in turn, …

Gps-Denied Localization Of Daughter-Ships In A Mother-Daughter Ship Collaborative Environment, Ethan W. Jacquin

Theses and Dissertations

This research investigates the possibility of using the communication link between a mothership and daughter-ship UAV and an Extended Kalman Filter algorithm as a replacement of GPS, assuming a ranging link exists between the mothership and daughter-ship and that the mothership is GPS-enabled. A simulation study examines the viability of the approach and the effect of parameters such as distance, altitude, roll angle, speed, ranging sensor noise, and inertial measurement unit uncertainty were considered. The magnitude of the errors between predicted and measured position were examined and a range of acceptable flight parameters was formed.

Optimizing A Bank Of Kalman Filters For Navigation Integrity, Luis E. Sepulveda

Theses and Dissertations

Alternative navigation is an area of research which employs a variety of sensor technologies to provide a navigation solution in Global Navigation Satellite System degraded or denied environments. The Autonomy and Navigation Technology Center at the Air Force Institute of Technology has recently developed the Autonomous and Resilient Management of All-source Sensors (ARMAS) navigation framework which utilizes an array of Kalman Filters to provide a navigation solution resilient to sensor failures. The Kalman Filter array size increases exponentially as system sensors and detectable faults are scaled up, which in turn increases the computational power required to run ARMAS in areal-world …

Automated Find Fix And Track With A Medium Altitude Long Endurance Remotely Piloted Aircraft, Aubrey L. Olson

Theses and Dissertations

A limitation in RPA ISR operations is loss of target track if the command link is severed. For an RPA to effectively execute the ISR mission without a command link, it needs the capability to F2T targets autonomously. Automated Find Fix and Track (AFFTRAC) was developed to help solve this problem by demonstrating a proof of concept tactical autopilot. Monocular stereo vision was used to process sequential images acquired during orbit to produce a partial structural point cloud of the original structure. This partial structural point cloud was then exploited to create a holding area density for the aircraft to …

Real-Time Aerial Magnetic And Vision-Aided Navigation, Daniel J. Clarke

Theses and Dissertations

Aerial magnetic navigation has shown to be a viable alternative navigation method that has the potential for world-wide availability, to include over oceans. Obtaining GPS-level accuracy using magnetic navigation alone is challenging, but magnetic navigation can be combined with other alternative navigation methods that are more posed to obtaining GPS-level accuracy in their current state. This research presents an aerial navigation solution combining magnetic navigation and vision-aided navigation to aid an inertial navigation system (INS). The navigation solution was demonstrated in real-time playback using simulated magnetic field measurements and flight-test captured visual imagery. Additionally, the navigation solution was flight-tested on …

Propose Of Architecture Design For Early Warning System With Space And Terrestrial Infrastructure, Akihiko Nishino

CESUN Conference

The purpose of this research is to design an architecture of early warning system with Global Navigation Satellite System (GNSS) and terrestrial infrastructure for improving a coverage of disaster information dissemination. In the proposed architecture, segments and information flow are identified in order to introduce an early warning system to target areas where there are no such kinds of public alert distribution. It can be adapted worldwide by combining GNSS satellite and terrestrial infrastructure. At the beginning of disaster, information will be sent from the agency via GNSS to terrestrial infrastructure, widely used such as a siren and a public …

Electromagnetic Formation Control Using Frequency Multiplexing, Zahra Abbasi

Theses and Dissertations--Mechanical Engineering

This dissertation addresses control of relative positions and orientations of formation flying satellites using magnetic interactions. Electromagnetic formation flight (EMFF) is implemented, in which each satellite is equipped with a set of electromagnetic coils to generate an electromagnetic field. Traditional EMFF technique applies DC magnetic fields which lead to a nonlinear and highly coupled formation dynamics that allow for only position or orientation control of the satellites. We present a new frequency multiplexing method, which is a technique that uses multi-frequency sinusoidal controls, to approximately decouple the formation dynamics and to provide enough controls for both position and orientation control. …

Resilience For Multi-Filter All-Source Navigation Framework With Integrity, Jonathon S. Gipson, Robert C. Leishman

Faculty Publications

The Autonomous and Resilient Management of All-source Sensors (ARMAS) framework monitors residual-space test statistics across unique sensor-exclusion banks of filters, (known as subfilters) to provide a resilient, fault-resistant all-source navigation architecture with assurance. A critical assumption of this architecture, demonstrated in this paper, is fully overlapping state observability across all subfilters. All-source sensors, particularly those that only provide partial state information (altimeters, TDoA, AOB, etc.) do not intrinsically meet this requirement.
This paper presents a novel method to monitor real-time overlapping position state observability and introduces an "observability bank" within the ARMAS framework, known as Stable Observability Monitoring (SOM). SOM …

Planetary Rover Inertial Navigation Applications: Pseudo Measurements And Wheel Terrain Interactions, Cagri Kilic

Graduate Theses, Dissertations, and Problem Reports

Accurate localization is a critical component of any robotic system. During planetary missions, these systems are often limited by energy sources and slow spacecraft computers. Using proprioceptive localization (e.g., using an inertial measurement unit and wheel encoders) without external aiding is insufficient for accurate localization. This is mainly due to the integrated and unbounded errors of the inertial navigation solutions and the drifted position information from wheel encoders caused by wheel slippage. For this reason, planetary rovers often utilize exteroceptive (e.g., vision-based) sensors. On the one hand, localization with proprioceptive sensors is straightforward, computationally efficient, and continuous. On the other …

Leveraging Aircraft Transponder Signals For Measuring Aircraft Fleet Mix At Non-Towered Airports, Chuyang Yang, John Mott, Darcy M. Bullock

International Journal of Aviation, Aeronautics, and Aerospace

The general aviation sector has contributed significantly to the overall growth of the aviation industry. Fleet mix and operations information is important for the analysis of both the safety and the environmental and economic impact of general aviation activity. Factual data on the impact of environment and safety is particularly important, given the scarcity of airport improvement funds and the strong stakeholder engagement that often occurs when airport investments are evaluated. The research presented herein evaluates Mode S short and extended squitter data collected from three general aviation airports over a one-month period. This article demonstrates that by utilizing the …

Analyzing And Improving Calculation And Tuning Process For A Uav, Laurel Wardell

Williams Honors College, Honors Research Projects

The nature of this project is confidential and cannot be disclosed in detail. Generally, this project deals with the analysis of a control system of a UAV with several electric motors and gimbals. The goal of this analysis is to improve control calculations for increased stability. In addition, development has been started on an application to streamline the tuning of gains for this particular controller, allowing for more efficient use of precious flight time.

Design And Testing Of A Feed-Forward Control System For Deployable Vortex Generators Dependent On Angle Of Attack, Solomon B. Whitmire, Christopher J. Chapanar, Kirklin M. Anderson, Nickalus R. Amon, Daniel W. Chech

Williams Honors College, Honors Research Projects

A vortex generator (VG hereafter) is a common feature of an aircraft wing that disturbs the flow on the leading edge of the wing, thus energizing the boundary layer and reducing flow separation. For an aircraft experiencing flow separation, VGs can increase the lift-to-drag ratio of the wing and prevent stall; however, if flow separation isn’t an issue, the unnecessary frontal area of the VGs has the potential to produce parasitic drag. This study seeks to determine whether the use of a deployment system can improve the performance of VG’s by raising or lowering them depending on the angle of …

Comparative Analysis Of Different Classes Of On-Line State Estimators For Aerodynamics Angles And True Airspeed Sensors For Applications To The Sensor Failure Problem, Alexandra Anne Augsberger

Graduate Theses, Dissertations, and Problem Reports

Throughout aviation history, there have been numerous incidents due to sensor failure that have caused a range of issues from loss of control of the aircraft to crashes resulting in loss of human life. Although there are many hardware-based solutions to this problem, the threat of control hardware failure still exists. This work investigates the efficacy of implementing neural networks (NN) and Kalman filters (KF) to solve the accommodation portion of the sensor failure detection, identification, and accommodation (SFDIA) problem through on-line real-time estimation of specific aircraft dynamic parameters. The implementation of on-line estimation architectures into the aircraft flight control …

Localization Algorithms For Gnss-Denied And Challenging Environments, Chizhao Yang

Graduate Theses, Dissertations, and Problem Reports

In this dissertation, the problem about localization in GNSS-denied and challenging environments is addressed. Specifically, the challenging environments discussed in this dissertation include two different types, environments including only low-resolution features and environments containing moving objects. To achieve accurate pose estimates, the errors are always bounded through matching observations from sensors with surrounding environments. These challenging environments, unfortunately, would bring troubles into matching related methods, such as "fingerprint" matching, and ICP. For instance, in environments with low-resolution features, the on-board sensor measurements could match to multiple positions on a map, which creates ambiguity; in environments with moving objects included, the …

Attitude Control And Consensus On So(3) Using Sinusoids: Theory And Application To Small Satellites, Roshan Anandrao Chavan

Theses and Dissertations--Mechanical Engineering

We present and analyze kinematic-level and dynamic-level feedback control algorithms for single agent attitude control and multi-agent attitude consensus on SO(3). The kinematic-level algorithms yield attitude feedback controls that are piecewise-continuous sinusoidal angular velocities. The dynamic-level algorithms yield attitude feedback controls that are relative angles of rotational-mass actuators, which are continuous but only piecewise continuously differentiable sinusoids. Furthermore, the dynamic-level algorithms are designed to accommodate actuator stroke constraint. We present application of the dynamic-level control algorithms to attitude control and consensus of small-satellites.

Predictability Improvement Of Scheduled Flights Departure Time Variation Using Supervised Machine Learning, Deepudev Sahadevan, Palanisamy Ponnusamy Dr, Manjunath K. Nelli Mr, Varun P. Gopi Dr

International Journal of Aviation, Aeronautics, and Aerospace

The departure time uncertainty exacerbates the inaccuracy of arrival time estimation and demand for arrival slots, particularly for movements to capacity constrained airports. The Estimated Take-Off Time (ETOT) or Estimated Departure Time(ETD) for each individual flight is currently derived from Air Traffic Flow Management System (ATFMS), which are solely determined based on individual flight plan Estimated Off Block Time(EOBT) or subsequent delays updated by Airline. Even if normal weather conditions prevail, aircraft departure times will differ from ETOTs determined by the ATFMS due to a number of factors such as congestion, early/delayed inbound flight (linked flights), reactionary delays and air …

Digitalization Of Educational And Methodological Support For The Training Of Aviation Dispatchers, Zair Ziyaevich Shamsiev

International Journal of Aviation, Aeronautics, and Aerospace

The tasks of improving the educational process of training civil aviation dispatchers on the basis of the development and implementation of digital teaching aids are considered. Legislative and regulatory documents are accepted as an object of digitalization. The end result of the research is expressed in the provision of the educational process with a special electronic educational complex, which has the functions of providing the necessary information and conducting practical exercises to deepen, consolidate and control knowledge in the field of aviation documents.

A Mathematical Analysis Of The Wind Triangle Problem And An Inquiry Of True Airspeed Calculations In Supersonic Flight, Leonard T. Huang, Lisa I. Cummings

International Journal of Aviation, Aeronautics, and Aerospace

In the first half of this paper, we present a fresh perspective toward the Wind Triangle Problem in aerial navigation by deriving necessary and sufficient conditions, which we call "go/no-go conditions", for the existence/non-existence of a solution of the problem. Although our derivation is based on simple trigonometry and basic properties of quadratic functions, it is mathematically rigorous. We also offer examples to demonstrate how easy it is to check these conditions graphically. In the second half of this paper, we use function theory to re-examine another problem in aerial navigation, namely, that of computing true airspeed — even in …

Uncertainty Estimation For Stereo Visual Odometry, Derek W. Ross

Graduate Theses, Dissertations, and Problem Reports

Over the past few decades, unmanned aerial vehicles (UAVs) have been increasingly popular for use in locations that are lacking, or have unreliable global navigation satellite system (GNSS) availability. One of the more popular localization techniques for quadrotors is the use of visual odometry (VO) through monocular, RGB-D, or stereo cameras. With primary applications in the context of Simultaneous Localization And Mapping (SLAM) and indoor navigation, VO is largely used in combination with other sensors through Bayesian filters, namely Extended Kalman Filter (EKF) or Particle Filter. This work investigates the accuracy of two standard covariance estimation techniques for a feature-based …

Increasing The Reliability Of Software Systems On Small Satellites Using Software-Based Simulation Of The Embedded System, Matthew D. Grubb

Graduate Theses, Dissertations, and Problem Reports

The utility of Small Satellites (SmallSats) for technology demonstrations and scientific research has been proven over the past few decades by governments, universities, and private companies. While the research and technology demonstration objectives that can be provided by these SmallSats are becoming similar to larger spacecraft, their reliability still falls behind. This is in part due to the reduced cost of SmallSat missions in comparison to large spacecraft, which requires cheaper components, rapid development schedules, and accepted risk. In these missions, the importance of the flight software is often overlooked, and the software is rushed through development and not fully …

Active Localization For Robotic Systems: Algorithms And Cost Metrics, Jared Strader

Graduate Theses, Dissertations, and Problem Reports

In the real world, a robotic system must operate in the presence of motion and sensing uncertainty. This is caused by the fact that the motion of a robotic system is stochastic due to disturbances from the environment, and the states are only partially observable due noise in the sensor measurements. As a result, the true state of a robotic system is unknown, and estimation techniques must be used to infer the states from the belief, which is the probability distribution over all possible states. Accordingly, a robotic system must be capable of reasoning about the quality of the belief …

Planning Algorithms Under Uncertainty For A Team Of A Uav And A Ugv For Underground Exploration, Matteo De Petrillo

Graduate Theses, Dissertations, and Problem Reports

Robots’ autonomy has been studied for decades in different environments, but only recently, thanks to the advance in technology and interests, robots for underground exploration gained more attention. Due to the many challenges that any robot must face in such harsh environments, this remains an challenging and complex problem to solve.

As technology became cheaper and more accessible, the use of robots for underground ex- ploration increased. One of the main challenges is concerned with robot localization, which is not easily provided by any Global Navigation Services System (GNSS). Many developments have been achieved for indoor mobile ground robots, making …

Bibliometric Review On Inertial Sensors Based Position Estimation Using Sensor Fusion, Animesh Mishra, Hamshita Kancharlapalli, Ankit Kumar, Aditya Chauhan, Parag Narkhede

Library Philosophy and Practice (e-journal)

Background: This paper analyzes the position estimation of UAV in a 3D environment, on the basis of inertial sensors and sensor fusion algorithm, done from the year 1994 to 2020. This paper contains various bibliometric analyses previously done on this topic.

Methods: The content for this topic was taken from the popular Scopus database. The Scopus provides many filters for searching databases with different document categories like document by year, country, etc. The research carried in this paper also includes co-authorship, citation analysis, etc.

Results: A total of 345 articles were obtained from the last 20 years, on the topic …

Dji Drone Modification, Sean Lacey, Seth Mancuso, Bryce Mckenzie

Williams Honors College, Honors Research Projects

For this project, we set out to create a lightweight carrying case that would be mounted to a DJI Phantom 3. This case is designed to transport small packages, such as medications, from a delivery vehicle to their final destination. Based on our maximum drone lifting capacity of 600 grams, our case, servomotor, and contents had to weigh less than or equal to that value. The coronavirus pandemic has led to an increase in contactless delivery options along with the push for immunocompromised people to avoid contact with people that may be sick. Our product would help transport necessary supplies …

Evaluation Of Murrell’S Ekf-Based Attitude Estimation Algorithm For Exploiting Multiple Attitude Sensor Configurations, Sharanabasaweshwara Asundi, Norman Fitz-Coy, Haniph Latchman

Mechanical & Aerospace Engineering Faculty Publications

Pico- and nano-satellites, due to their form factor and size, are limited in accommodating multiple or redundant attitude sensors. For such satellites, Murrell's implementation of the extended Kalman filter (EKF) can be exploited to accommodate multiple sensor configurations from a set of non redundant attitude sensors. The paper describes such an implementation involving a sun sensor suite and a magnetometer as attitude sensors. The implementation exploits Murrell's EKF to enable three sensor configurations, which can be operationally commanded, for satellite attitude estimation. Among the three attitude estimation schemes, (i) sun sensor suite and magnetometer, (ii) magnetic field vector and its …