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Fault Diagnosis And Accommodation In Quadrotor Simultaneous Localization And Mapping Systems, Anthony J. Green
Fault Diagnosis And Accommodation In Quadrotor Simultaneous Localization And Mapping Systems, Anthony J. Green
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Simultaneous Localization and Mapping (SLAM) is the process of using distance measurements to points in the surrounding environment to build a digital map and perform localization. It has been observed that featureless environments like tunnels or straight hallways will cause positioning faults in SLAM. This research investigates the fault diagnosis and accommodation problem for a laser-rangefinder-based SLAM systems on a quadrotor. A potential solution of using optical flow as velocity estimate and an extended Kalman filter (EKF) to perform position estimation is proposed. A fault diagnosis method for detecting faults in positional SLAM data or optical flow velocity data is …
Development Of A Robust And Tunable Aircraft Guidance Algorithm, Jacob R. Spangenberg
Development Of A Robust And Tunable Aircraft Guidance Algorithm, Jacob R. Spangenberg
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A set of guidance control laws is developed for application to a reduced order dynamic aircraft model. A feedback control formulation utilizing a linear quadratic regulator (LQR) is developed, together with methods for easing the design burden associated with gain tuning. Metrics are developed to assess the stability margin of the controller over the full flight envelope of a notional unmanned aerial vehicle (UAV) model. A feedforward control path is then added to the architecture. The performance of the guidance control laws is assessed through time domain step response metrics as well as through execution of a design mission. The …
Development Of A Robust And Tunable Aircraft Guidance Algorithm, Jacob R. Spangenberg
Development Of A Robust And Tunable Aircraft Guidance Algorithm, Jacob R. Spangenberg
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A set of guidance control laws is developed for application to a reduced order dynamic aircraft model. A feedback control formulation utilizing a linear quadratic regulator (LQR) is developed, together with methods for easing the design burden associated with gain tuning. Metrics are developed to assess the stability margin of the controller over the full flight envelope of a notional unmanned aerial vehicle (UAV) model. A feedforward control path is then added to the architecture. The performance of the guidance control laws is assessed through time domain step response metrics as well as through execution of a design mission. The …
Edge Processing Of Image For Uas Sense And Avoidance, Christopher J. Rave
Edge Processing Of Image For Uas Sense And Avoidance, Christopher J. Rave
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Today there is a large market for Unmanned Aerial Systems. Although most current systems are remotely piloted by operators on the ground, increasingly, many of these systems will use some sort of automatic flight controller to help mitigate new challenges, due to their deployment at growing scale. These challenges include, but are not limited to, shortage of FAA-certified UAS pilots, transmission bandwidth and delay constraints and cyber security threats associated with wireless networking, profitability of operations constrained by energy capacity and efficiency and air dynamics planning, and etc. In order to address these rising challenges, this thesis is a part …
Adaptive Two-Stage Edge-Centric Architecture For Deeply-Learned Embedded Real-Time Target Classification In Aerospace Sense-And-Avoidance Applications, Nicholas A. Speranza
Adaptive Two-Stage Edge-Centric Architecture For Deeply-Learned Embedded Real-Time Target Classification In Aerospace Sense-And-Avoidance Applications, Nicholas A. Speranza
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With the growing number of Unmanned Aircraft Systems, current network-centric architectures present limitations in meeting real-time and time-critical requirements. Current methods utilizing centralized off-platform processing have inherent energy inefficiencies, scalability challenges, performance concerns, and cyber vulnerabilities. In this dissertation, an adaptive, two-stage, energy-efficient, edge-centric architecture is proposed to address these limitations. A novel, edge-centric Sense-and-Avoidance architecture framework is presented, and a corresponding prototype is developed using commercial hardware to validate the proposed architecture. Instead of a network-centric approach, processing is distributed at the logical edge of the sensors, and organized as Detection and Classification Subsystems. Classical machine vision algorithms are …
System Identification And Model-Based Control Of Quadcopter Uavs, Andrew P. Szabo
System Identification And Model-Based Control Of Quadcopter Uavs, Andrew P. Szabo
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As control systems become more sophisticated, more accurate system models are needed for control law design and simulation. In this research, a nonlinear dynamic model of a quadcopter UAV is presented and model parameters are estimated off-line using in-flight experimental data. In addition, a model-based classical control law for the quadcopter UAV is designed, simulated, and then deployed in UAV flight tests. The intent of this research is to identify a model which may be simple enough to easily use for control law design, and accurate enough for simulation. In addition, a model-based classical control law is designed to for …
Implementation Of Unmanned Aerial Vehicles Reporting Plume Cloud Concentration Values In A 3d Simulation Environment, Emily Catherine Novak
Implementation Of Unmanned Aerial Vehicles Reporting Plume Cloud Concentration Values In A 3d Simulation Environment, Emily Catherine Novak
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Unmanned aerial vehicles, or UAVs, have the potential to vastly improve plume cloud tracking at low cost. Plume clouds can be produced from blast mining, chemical warfare, unintended man-made disasters, and natural causes. This thesis provides implementation of the capability to simulate a 3D environment in which UAVs are individually controlled and each report a plume's concentration value at a specific location. It leverages existing industry standard technologies, including the PX4 autopilot system, the Gazebo simulation environment, the Robot Operating System (ROS), and QGroundControl. The provided system integrates the existing tools with a plume model plug-in that provides simulated plume …
Overwhelming The Saa System Of Delivery Uavs By Drone Swarming, Barry Lynn Pfaff
Overwhelming The Saa System Of Delivery Uavs By Drone Swarming, Barry Lynn Pfaff
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As the Internet continues to replace the brick-and-mortar store as the main place for purchasing goods, web-based companies are looking for ways to reduce the cost of delivering those goods. The use of Unmanned Aerial Vehicles, or UAVs, is one delivery method that is increasingly being used. These UAVs can be programmed with delivery routes and destinations and can complete the job while requiring limited intervention from human controllers. Sense and Avoidance (SAA) systems have recently been incorporated into these UAVs so that they can detect objects in their flight path, reroute the UAV accordingly and operate even more autonomously. …
Development Of Guidance Laws For A Reduced Order Dynamic Aircraft Model, Jack W. Brendlinger
Development Of Guidance Laws For A Reduced Order Dynamic Aircraft Model, Jack W. Brendlinger
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A set of guidance control laws has been developed for enabling three distinct modes of operation of a reduced order dynamic aircraft model. These include 1) a waypoint following control law, 2) a trajectory tracking control law, and 3) a set of kinematically constrained control laws for reaching a commanded altitude, speed or heading. The formulation of the reduced order model is presented so that the capabilities and limitations of the model are understood, and so that the interface architecture between the controllers and the plant is clearly defined. The controller formulations are then presented, together with sample results. The …
Analysis Of A Fuel Cell Combustor In A Solid Oxide Fuel Cell Hybrid Gas Turbine Power System For Aerospace Application, Ryan R. Sinnamon
Analysis Of A Fuel Cell Combustor In A Solid Oxide Fuel Cell Hybrid Gas Turbine Power System For Aerospace Application, Ryan R. Sinnamon
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Over the last few years, fuel cell technology has significantly advanced and has become a mode of clean power generation for many engineering applications. Currently the dominant application for fuel cell technology is with stationary power generation. Very little has been published for applications on mobile platforms, such as unmanned aerial vehicles. With unmanned aerial vehicles being used more frequently for national defense and reconnaissance, there is a need for a more efficiency, longer endurance power system that can support the increased electrical loads onboard. It has already been proven by others that fuel cell gas turbine hybrid systems can …
Measurement Of Static And Dynamic Performance Characteristics Of Electric Propulsion Systems, Aron Jon Brezina
Measurement Of Static And Dynamic Performance Characteristics Of Electric Propulsion Systems, Aron Jon Brezina
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Today's unmanned aerial vehicles are being utilized by numerous groups around the world for various missions. Most of the smaller vehicles that have been developed use commercially-off-the-shelf parts, and little information about the performance characteristics of the propulsion systems is available in the archival literature. In light of this, the aim of the present research was to determine the performance of various small-scale propellers in the 4.0 to 6.0 inch diameter range driven by an electric motor. An experimental test stand was designed and constructed in which the propeller/electric motor was mounted in a wind tunnel for both static and …
Adaptive Noise Reduction Techniques For Airborne Acoustic Sensors, Ryan Michael Fuller
Adaptive Noise Reduction Techniques For Airborne Acoustic Sensors, Ryan Michael Fuller
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Ground and marine based acoustic arrays are currently employed in a variety of military and civilian applications for the purpose of locating and identifying sources of interest. An airborne acoustic array could perform an identical role, while providing the ability to cover a larger area and pursue a target. In order to implement such a system, steps must be taken to attenuate environmental noise that interferes with the signal of interest. In this thesis, we discuss the noise sources present in an airborne environment, present currently available methods for mitigation of these sources, and propose the use of adaptive noise …
Cognitively Sensitive User Interface For Command And Control Applications, Michael James Findler
Cognitively Sensitive User Interface For Command And Control Applications, Michael James Findler
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While there are broad guidelines for display or user interface design, creating effective human-computer interfaces for complex, dynamic systems control is challenging. Ad hoc approaches which consider the human as an afterthought are limiting. This research proposed a systematic approach to human / computer interface design that focuses on both the semantic and syntactic aspects of display design in the context of human-in-the-loop supervisory control of intelligent, autonomous multi-agent simulated unmanned aerial vehicles (UAVs). A systematic way to understand what needs to be displayed, how it should be displayed, and how the integrated system needs to be assessed is outlined …
Autopilot Development For An Rc Helicopter, Mark C. Arlinghaus
Autopilot Development For An Rc Helicopter, Mark C. Arlinghaus
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The development of an autopilot system for an RC helicopter presents interesting challengesfrom both a hardware and controls standpoint. The system detailed in this thesis utilizes a 13 state Extended Kalman Filter (EKF) to fuse sensor data and provide a position/velocity/attitude estimate. A novel, state of the art hybrid PID/LQR controller is developed and compared with a full state Linear Quadratic Regulator (LQR). The hybrid controller uses a proportional position, PID velocity outer loop coupled with an inner loop LQR for attitude control. The entire system is developed and implemented in hardware to produce a functional autopilot. The unit was …