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Physical Sciences and Mathematics

Theses/Dissertations

2008

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Development Of A Night Vision Goggle Heads Up Display For Paratrooper Guidance, Fernando Ontiveros Jun 2008

Development Of A Night Vision Goggle Heads Up Display For Paratrooper Guidance, Fernando Ontiveros

Theses and Dissertations

This thesis provides the proof of concept for the development and implementation of a Global Positioning System (GPS) display via Night Vision Goggles (NVG) Heads-Up Display (HUD) for paratroopers. The system has been designed for soldiers who will be able to utilize the technology in the form of a processing system worn in an ammo pouch and displayed via NVG HUD as a tunnel in the sky. The tunnel in the sky display design is essentially a series of boxes displayed within the goggle's HUD leading the paratrooper to the desired Landing Zone (LZ). The algorithm developed receives GPS and …


Tightly Integrating Optical And Inertial Sensors For Navigation Using The Ukf, Sedat Ebcin Mar 2008

Tightly Integrating Optical And Inertial Sensors For Navigation Using The Ukf, Sedat Ebcin

Theses and Dissertations

The motivation of this research is to address the benefits of tightly integrating optical and inertial sensors where GNSS signals are not available. The research begins with describing the navigation problem. Then, error and measurement models are presented. Given a set of features, a feature detection and projection algorithm is developed which utilizes inertial measurements to predict vectors in the feature space between images. The unscented Kalman filter is applied to the navigation system using the inertial measurements and feature matches to estimate the navigation trajectory. Finally, the image-aided navigation algorithm is tested using a simulation and an experiment. As …


Analysis Of Non-Uniform Gain For Control Of A Deformable Mirror In An Adaptive-Optics System, Kevin P. Vitayaudom Mar 2008

Analysis Of Non-Uniform Gain For Control Of A Deformable Mirror In An Adaptive-Optics System, Kevin P. Vitayaudom

Theses and Dissertations

The Air Force Research Laboratory’s Sodium Guidestar Adaptive Optics for Space Situational Awareness program (NGAS) has sponsored research on spatially non-uniform gain for the servo-loop controller of an adaptive optics (AO) system. The edge subapertures of a Shack-Hartmann wavefront sensor have lower signal-to-noise ratios and are more susceptible to measurement errors than fully illuminated center subapertures. These measurement errors produce errant commands over the corresponding edge actuators and can induce instabilities over these regions in strong turbulence conditions. The objective of this research was to develop and experimentally verify the use of spatially varying gain maps on the servo-loop controller …


Multi-Objective Uav Mission Planning Using Evolutionary Computation, Adam J. Pohl Mar 2008

Multi-Objective Uav Mission Planning Using Evolutionary Computation, Adam J. Pohl

Theses and Dissertations

This investigation purports to develop a new model for multiple autonomous aircraft mission routing. Previous research both related and unrelated to this endeavor have used classic combinatoric problems as models for Unmanned Aerial Vehicle (UAV) routing and mission planning. This document presents the concept of the Swarm Routing Problem (SRP) as a new combinatorics problem for use in modeling UAV swarm routing, developed as a variant of the Vehicle Routing Problem with Time Windows (VRPTW). The SRP removes the single vehicle per target restraint and changes the customer satisfaction requirement to one of vehicle on location volume. The impact of …


Behavior-Based Power Management In Autonomous Mobile Robots, Charles A. Fetzek Mar 2008

Behavior-Based Power Management In Autonomous Mobile Robots, Charles A. Fetzek

Theses and Dissertations

Current attempts to prolong the life of a robot on a single battery charge focus on lowering the operating frequency of the onboard hardware, or allowing devices to go to sleep during idle states. These techniques have much overhead and do not come built in to the underlying robotic architecture. In this thesis, battery life is greatly extended through development of a behavior-based power management system, including a Markov decision process power planner, thereby allowing future robots increased time to operate and loiter in their required domain. Behavior-based power management examines sensors needed by the currently active behavior set and …


A Secure Group Communication Architecture For A Swarm Of Autonomous Unmanned Aerial Vehicles, Adrian N. Phillips Mar 2008

A Secure Group Communication Architecture For A Swarm Of Autonomous Unmanned Aerial Vehicles, Adrian N. Phillips

Theses and Dissertations

This thesis investigates the application of a secure group communication architecture to a swarm of autonomous unmanned aerial vehicles (UAVs). A multicast secure group communication architecture for the low earth orbit (LEO) satellite environment is evaluated to determine if it can be effectively adapted to a swarm of UAVs and provide secure, scalable, and efficient communications. The performance of the proposed security architecture is evaluated with two other commonly used architectures using a discrete event computer simulation developed using MatLab. Performance is evaluated in terms of the scalability and efficiency of the group key distribution and management scheme when the …


Collision Avoidance For Uavs Using Optic Flow Measurement With Line Of Sight Rate Equalization And Looming, Paul J. Shelnutt Mar 2008

Collision Avoidance For Uavs Using Optic Flow Measurement With Line Of Sight Rate Equalization And Looming, Paul J. Shelnutt

Theses and Dissertations

A series of simplified scenarios is investigated whereby an optical flow balancing guidance law is used to avoid obstacles by steering an air vehicle between fixed objects/obstacles. These obstacles are registered as specific points that can be representative of features in a scene. The obstacles appear in the field of view of a single forward looking camera. First a 2-D analysis is presented where the rate of the line of sight from the vehicle to each of the obstacles to be avoided is measured. The analysis proceeds by initially using no field of view (FOV) limitations, then applying FOV restrictions, …


Dynamic Behavior Sequencing In A Hybrid Robot Architecture, Jeffrey P. Duffy Mar 2008

Dynamic Behavior Sequencing In A Hybrid Robot Architecture, Jeffrey P. Duffy

Theses and Dissertations

Hybrid robot control architectures separate plans, coordination, and actions into separate processing layers to provide deliberative and reactive functionality. This approach promotes more complex systems that perform well in goal-oriented and dynamic environments. In various architectures, the connections and contents of the functional layers are tightly coupled so system updates and changes require major changes throughout the system. This work proposes an abstract behavior representation, a dynamic behavior hierarchy generation algorithm, and an architecture design to reduce this major change incorporation process. The behavior representation provides an abstract interface for loose coupling of behavior planning and execution components. The hierarchy …


Exploitation Of Self Organization In Uav Swarms For Optimization In Combat Environments, Dustin J. Nowak Mar 2008

Exploitation Of Self Organization In Uav Swarms For Optimization In Combat Environments, Dustin J. Nowak

Theses and Dissertations

This investigation focuses primarily on the development of effective target engagement for unmanned aerial vehicle (UAV) swarms using autonomous self-organized cooperative control. This development required the design of a new abstract UAV swarm control model which flows from an abstract Markov structure, a Partially Observable Markov Decision Process. Self-organization features, bio-inspired attack concepts, evolutionary computation (multi-objective genetic algorithms, differential evolution), and feedback from environmental awareness are instantiated within this model. The associated decomposition technique focuses on the iterative deconstruction of the problem domain state and dynamically building-up of self organizational rules as related to the problem domain environment. Resulting emergent …


Digital Signal Processing Leveraged For Intrusion Detection, Theodore J. Erickson Mar 2008

Digital Signal Processing Leveraged For Intrusion Detection, Theodore J. Erickson

Theses and Dissertations

This thesis describes the development and evaluation of a novel system called the Network Attack Characterization Tool (NACT). The NACT employs digital signal processing to detect network intrusions, by exploiting the Lomb-Scargle periodogram method to obtain a spectrum for sampled network traffic. The Lomb-Scargle method for generating a periodogram allows for the processing of unevenly sampled network data. This method for determining a periodogram has not yet been used for intrusion detection. The spectrum is examined to determine if features exist above a significance level chosen by the user. These features are considered an attack, triggering an alarm. Two traffic …


A Novel Communications Protocol Using Geographic Routing For Swarming Uavs Performing A Search Mission, Robert L. Lidowski Mar 2008

A Novel Communications Protocol Using Geographic Routing For Swarming Uavs Performing A Search Mission, Robert L. Lidowski

Theses and Dissertations

This research develops the UAV Search Mission Protocol (USMP) for swarming UAVs and determines the protocol's effect on search mission performance. It is hypothesized that geographically routing USMP messages improves search performance by providing geography-dependent data to locations where it impacts search decisions. It is also proposed that the swarm can use data collected by the geographic routing protocol to accurately determine UAV locations and avoid sending explicit location updates. The hypothesis is tested by developing several USMP designs that are combined with the Greedy Perimeter Stateless Routing (GPSR) protocol and a search mission swarm logic into a single network …