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Scott, Kevon KOcclusion-Aware Sensing and Coverage in Unmanned Aerial Vehicle (UAV) Networks
MS, University of Cincinnati, 2016, Engineering and Applied Science: Computer Engineering
The use of small and miniature Unmanned Aerial Vehicles (UAVs) for remote sensing and surveillance applications has become increasingly popular in the last two decades. Networks of UAVs, capable of providing flexible aerial views over large areas, are playing important roles in today's distributed sensing systems. Since camera sensors are sensitive to occlusions, it is more challenging to deploy UAVs for sensing in geometrically complex environments, such as dense urban areas and mountainous terrains. The intermittent connectivity in a sparse UAV network also makes it challenging to efficiently gather sensed multimedia data. This thesis is composed of two pieces of work. In the first piece of work, a new occlusion-aware UAV coverage technique with the objective of sensing a target area with satisfactory spatial resolution subject to the energy constraints of UAVs is proposed. An occlusion-aware waypoint generation algorithm is first designed to find the best set of waypoints for taking pictures in a target area. The selected waypoints are then assigned to multiple UAVs by solving a vehicle routing problem (VRP), which is formulated to minimize the maximum energy for the UAVs to travel through the waypoints. A genetic algorithm is designed to solve the VRP problem. Evaluation results show that the proposed coverage technique can reduce energy consumption while achieving better coverage than traditional coverage path planning techniques for UAVs. In the second piece of work, a communication scheme is designed to deliver the images sensed by a set of mobile survey UAVs to a static base station through the assistance of a relay UAV. Given the planned routes of the survey UAVs, a set of relay waypoints are found for the relay UAV to meet the survey UAVs and receive the sensed images. An Online Message Relaying technique (OMR) is proposed to schedule the relay UAV to collect images. Without any global collaboration between the relay UAV and the survey UAVs, OMR utilizes a markov decision process (MDP) that determines the best schedules for the relay UAV such that the image acquisition rate could be maximized. Evaluation results show that the proposed relaying technique outperforms traditional relaying techniques, such as the traveling salesman problem (TSP) and the random walk, in terms of end-to-end delay and frame delivery ratio.

Committee:

Rui Dai, Ph.D. (Committee Chair); Dharma Agrawal, D.Sc. (Committee Member); Carla Purdy, Ph.D. (Committee Member)

Subjects:

Computer Engineering

Keywords:

Unmanned Aerial Vehicle;UAV;Occlusion;FANET;Flying Ad-Hoc Networks;Remote Sensing

Larson, Matthew DavidMonitoring Multi-Depth Suspended Sediment Loads in Lake Erie's Maumee River using Landsat 8 and Unmanned Aerial Vehicle (UAV) Imagery
Master of Science (MS), Bowling Green State University, 2017, Geology
Suspended sediment in water bodies is a considerable environmental concern. Traditional sampling methods for suspended sediment are time-consuming as they involve vertical and spatial point-sampling. Remote sensing (RS) is an alternative to in-situ measurements and it is capable of monitoring suspended sediments in shallow waters spatially at large scales. Use of RS technology to map suspended sediment concentrations (SSC) depends on sensor type and its capability `to see through’ the water column at given surface and water column conditions. This study examined the capabilities of RS technology to spatially quantify SSC at multi-depth intervals within the Maumee River, Ohio. Water samples were collected and analyzed for SSC in May, June, and October at depths of 0.5 ft., 2 ft., 3 ft., and 6 ft. Landsat 8, surface hyperspectral measurements (aggregated to simulate sensors), and MicaSense Sequoia camera onboard an unmanned aerial vehicle (UAV) were used. Single spectral bands, ratios, and multiple bands/ratios were examined in developing algorithms relating RS and field measurements. Linear regression models provided the best relationship for surface, Landsat 8, and UAV data throughout all depths. A 6 ft. depth had the highest correlation for surface (R2adj=0.93) and Landsat 8 (R2adj=0.79) data. For UAV a 3 ft. depth provided the best relationship (R2adj=0.52). Band ratios using nonlinear fitting provided good relationships (surface R2adj=0.72 and Landsat 8 R2adj=0.54) at 6 ft. as well. Results showed Landsat 8 more accurately measured suspended solids at 6 ft. than shallower depths. Regression equations and band ratios showed increasing relationships with SSC with increasing depth for Landsat 8 with an exception for 3 ft., which can occur due to stratification. UAV measurements produced best results for 3 ft. Algorithms with best results included ultra blue, blue, and green bands which are not typically used for quantifying SSC. Shorter wavelength bands (400 nm-550 nm) should be considered in waters with small suspended sediments as those found in the Maumee River. Equations were not transferable from one day to another. It is surmised that concentration thresholds of 40-60 mg/L play a role in equation derivation, as well as meteorological factors.

Committee:

Anita Simic (Advisor); Robert Vincent (Committee Member); James Evans (Committee Member)

Subjects:

Geological; Geology; Geotechnology; Hydrology; Remote Sensing; Sedimentary Geology

Keywords:

Remote sensing; surface water hydrology; geospatial; drone; unmanned aerial vehicle; ohio; maumee river; suspended sediment; water quality; multispectral sensor; river; sediment transport; algorithms; geology; geospatial;

Fuller, Ryan MichaelAdaptive Noise Reduction Techniques for Airborne Acoustic Sensors
Master of Science in Engineering (MSEgr), Wright State University, 2012, Electrical Engineering
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 cancellation techniques for removal of unwanted wind and engine noise. The least mean squares, affine projection, and extended recursive least squares algorithms are tested on recordings made aboard an airplane in-flight, and the results are presented. The algorithms provide upwards of 37dB of noise cancellation, and are able to filter the noise from a chirp with a signal to noise ratio of -20db with minimal mean square error. The experiment demonstrates that adaptive noise cancellation techniques are an effective method of suppressing unwanted acoustic noise in an airborne environment, but due to the complexity of the environment more sophisticated algorithms may be warranted.

Committee:

Brian Rigling, PhD (Committee Chair); Kefu Xue, PhD (Committee Member); Fred Garber, PhD (Committee Member)

Subjects:

Acoustics; Aerospace Engineering; Applied Mathematics; Electrical Engineering; Engineering; Remote Sensing

Keywords:

Adaptive Noise Cancellation; Adaptive Algorithms; Acoustic Sensors; Acoustic Eavesdropping; UAV; Unmanned Aerial Vehicle; Active Noise Reduction; Remote Sensing; Signal Processing; Acoustics

Rutkowski, Adam JA BIOLOGICALLY-INSPIRED SENSOR FUSION APPROACH TO TRACKING A WIND-BORNE ODOR IN THREE DIMENSIONS
Doctor of Philosophy, Case Western Reserve University, 2008, Mechanical Engineering
An autonomous vehicle that can track a wind-borne odor plume to its source could locate lost pets and people, pipeline breaks, illegal drug labs, or improvised explosive devices (IEDs). This work explores moth-inspired strategies for tracking a wind-borne odor plume with an aerial vehicle. When tracking an odor, moths counter-turn horizontally back and forth across the wind while generally progressing upwind. Previous studies suggest that moths maintain their altitude at the mean altitude of the odor plume and that the timing of their turns is controlled by an internal mechanism. The ability of moths to stabilize their altitude while tracking an odor plume was examined in a laboratory wind tunnel. It was hypothesized that an enriched visual environment in the lateral visual field would allow moths to stabilize their altitude. The moths did not maintain their altitude fixed at the mean altitude of the odor plume. Instead, they used a combination of horizontal and vertical undulations to search for odor in a plane normal to the wind direction while making upwind progress. The three dimensional observations of moth odor tracking inspired the design of strategies that direct an agent to control its turn rate in the wind-normal plane, and upwind speed, as independent functions of the measured odor concentration. The aerial agent estimates its egomotion, altitude, the wind velocity, and the ground structure using a new technique that fuses visual and mechanosensory input. Two odor tracking strategies – Spiraling and Spiraling5 - were developed and tested in simulation on an odor tracking software platform called OdorTracker. The behavior of the Spiraling strategy was dependent on the odor concentration while the Spiraling5 strategy was dependent on the time derivative of odor concentration. Using either strategy, the simulated agent approached the odor source with moth-like undulations in the vertical and horizontal directions without internal counter-turn timers; however, the Spirarling5 algorithm sometimes became unstable. Not only did the odor tracking strategies allow the tracking agent to reach the odor source, they also allowed the tracking agent to remain in the vicinity of the odor source for several seconds, which also agrees with moth behavior.

Committee:

Roger Quinn (Advisor)

Keywords:

odor tracking; odor tracing; guidance; vision; moth; Manduca sexta; olfaction; unmanned aerial vehicle; optic flow; robot

Brezina, Aron JonMeasurement of Static and Dynamic Performance Characteristics of Electric Propulsion Systems
Master of Science in Engineering (MSEgr), Wright State University, 2012, Mechanical Engineering
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 dynamic testing. Both static and dynamic results from the present experiment were compared to those from previous studies. For static testing, the coefficient of thrust, the coefficient of propeller power, and the overall efficiency, defined as the ratio of the propeller output power to the electrical input power, were plotted versus the propeller rotational speed. For dynamic testing, the rotational speed of the propeller was held constant at regular intervals while the freestream airspeed was increased from zero to the windmill state. The coefficient of thrust, the coefficient of power, the propeller efficiency and the overall efficiency were plotted versus the advance ratio for various rotational speeds. The thrust and torque were found to increase with rotational speed, propeller pitch and diameter, and decrease with airspeed. Using the present data and data from the archival and non-archival sources, it was found that the coefficient of thrust increases with propeller diameter for square propellers where D = P. The coefficient of thrust for a family of propellers (same manufacturer and application) was found to have a good correlation from static conditions to the windmill state. While the propeller efficiency was well correlated for this family of propellers, the goodness of fit parameter was improved by modifying the propeller efficiency with D/P.  

Committee:

Scott K. Thomas, PhD (Committee Chair); Haibo Dong, PhD (Committee Member); Zifeng Yang, PhD (Committee Member); Mitch Wolff, PhD (Committee Member)

Subjects:

Aerospace Engineering; Engineering; Mechanical Engineering

Keywords:

Propeller; Small Unmanned Aerial Vehicle; UAV; Electric Propulsion System; Advance Ratio; Low Reynolds Number; Wind Tunnel Testing

Bohn, Christopher A.In pursuit of a hidden evader
Doctor of Philosophy, The Ohio State University, 2004, Computer and Information Science
We define a game of pursuers seeking evaders on a grid, originally motivated by, but not limited to, the problem of unmanned aerial vehicles searching for moving targets. The pursuers have a speed advantage over the evaders but are incapable of determining an evader’s location unless a pursuer occupies the same location as that evader. The evaders, on the other hand, operate with unlimited luck and cunning: if it is possible for them to avoid the pursuers, they will. By treating the players as nondeterministic finite automata, we can model the game and use it as the input for a model checker. While model checkers normally are used to verify program correctness, we use the model checker to generate a pursuer-winning search strategy. We demonstrate this technique for the full model and then develop heuristics to reduce the model so we can address larger problem sizes. We further prove an upper bound on the minimum pursuer-winning speed; moreover, we show the bound is tight for a particular class of search strategies.

Committee:

Paolo Sivilotti (Advisor)

Subjects:

Computer Science

Keywords:

Model checking; Unmanned aerial vehicle; Pursuer-evader game

Simon, Jerry N.A Systems Approach to the Formulation of Unmanned Air Vehicle Detect, Sense, and Avoid Performance Requirements
Master of Science (MS), Ohio University, 2009, Electrical Engineering (Engineering and Technology)
Unmanned Aerial Vehicles (UAVs) are becoming more prevalent in military applications and through the success of these applications, many commercial usages have been derived. However, due to the recent development of UAVs, the Federal Aviation Administration (FAA) has not yet been able to develop performance requirements for the Detect, Sense, and Avoid (DSA) system of UAVs. For this reason, this study serves to explore the current capabilities of human general aviation (GA) pilots with regards to their see-and-avoid abilities. The midair collision rate over the past ten years and the average traffic around an average airport are also explored. With the analyzed data, a model is developed in order to extract the grounds for performance requirement for DSA systems. The determined DSA performance estimate can be used to further aid in the development of overall performance requirements for DSA systems.

Committee:

Michael Braasch, PhD (Advisor); Chris Bartone, PhD (Committee Member); Maarten Uijt De Haag, PhD (Committee Member); Zhen Zhu, PhD (Committee Member); William Kaufman, PhD (Other)

Subjects:

Electrical Engineering; Engineering

Keywords:

Unmanned Aerial Vehicle; UAV; Detect Sense and Avoid; DSA; See and Avoid

Seeds, Matthew LDiscourses in Disanthro Studies
MA, Kent State University, 2017, College of the Arts / School of Art
Specific to this discussion are the philosophical implications of surveillance, war and consumption; the decision making of the few adjusting the course of the many over time; and the endless possibilities of artificial autonomy that lie on the horizon. This art installation 'Rehabilitation Center' proposes an alternative reality within the context of the Anthropocene. One where there are no dark corners for closed-door decision making, where intrigue and play can heal the scars of deception and greed, where divisional rhetoric cannot withstand compassion and togetherness.

Committee:

Andrew Kuebeck (Committee Chair)

Subjects:

Art Criticism

Keywords:

Anthropocene ; Anthropocentrism ; Anthropocentric ; capitalism ; petro capitalism ; alternative reality ; resource wars ; oil ; birds ; drone ; drones ; UAV ; UFO ; unmanned aerial vehicle ; middle east ; black budget ; panopticon ; Disanthro ;

Wigmore, Oliver HenryAssessing Spatiotemporal Variability in Glacial Watershed Hydrology: Integrating Unmanned Aerial Vehicles and Field Hydrology, Cordillera Blanca, Peru.
Doctor of Philosophy, The Ohio State University, 2016, Geography
The glaciers of the Cordillera Blanca Peru are rapidly retreating as a result of climate change, altering the timing, quantity and quality of water available to downstream users. Changes in water availability have serious implications for ecosystems, human livelihoods and regional economies. This dissertation investigates spatiotemporal changes in the glacier hydrologic system of the Cordillera Blanca Peru. It includes three major components. First, I develop multispectral unmanned aerial vehicles (UAV) and kite platforms capable of operating at over 5000m in mountain regions. Secondly, I deploy these platforms to investigate processes of glacier change and surface/subsurface hydrology within the glacial valleys of the Cordillera Blanca. Finally, I integrate UAV datasets with traditional field hydrology to improve our understanding of the spatiotemporal variability in soil moisture and its role in moderating groundwater storage within the Cordillera Blanca. I designed and deployed UAVs on multiple missions at over 5000masl in the Cordillera Blanca, Peru. After describing the UAV design in Chapter 2, this dissertation reports on results of four studies that utilise the UAV to address research questions within the region. Chapter 3 comprehensively assesses the accuracy of photogrammetrically derived structure from motion (SfM) digital elevation models (DEMs), by quantitatively and qualitatively comparing the data against surveyed GPS positions and LiDAR DEMs. Finding that accuracy is as good if not superior to low density LiDAR, with the high density SfM point clouds retaining unique surface details. Chapter 4 investigates the dynamics of glacier change over the debris covered Llaca glacier. I document the importance of debris cover and surface features such as ice cliffs in controlling melt rates. Average glacier downwasting is 0.75m over one year but is highly heterogeneous. Ice cliff horizontal recession rates of up to 25m annual were measured illustrating the importance of debris thickness and ice exposure to the evolution of these systems. Only limited horizontal retreat of the glacier tongue was recorded, indicating that simple measurements of changes in aerial extent are inadequate for understanding actual changes in glacier ice quantity. In Chapter 5 I investigate spatial variability in surface soil moisture. By collecting multispectral (visible, near infrared and thermal infrared) imagery and using the temperature vegetation dryness index (TVDI) I generate 50cm pixel resolution estimates of soil moisture for two proglacial wetland/meadow study sites. Surface soil moisture is found to vary markedly over short distances and is negatively impacted by grazing practices. Through inspection of the multispectral UAV imagery I was able to identify surface and subsurface hydrologic pathways including groundwater springs from airborne thermal imagery. Finally in Chapter 6 I integrate the UAV findings with field instrumentation. I investigate spatiotemporal variability in soil moisture and groundwater table storage within the meadows and wetlands of the Cordillera Blanca. Key findings from the three study sites were the high rates of evapotranspiration, and the limited role of water stored in the groundwater table, and as soil moisture, in buffering dry season stream flow. However, the peatland soils were found to have very low bulk densities (~0.15g/cm3), and a high water storage capacity. Reaching 80-90% volumetric water content at saturation. Thus meadow and wetland systems in the Cordillera Blanca may still play an important role in reducing runoff and increasing groundwater recharge during the wet season, which is an important source of dry season stream flow. My results show that UAVs are an ideal method for studying heterogeneous landscapes at high resolution, and are thus highly suited for small scale studies within mountain regions. This dissertation provides a double faceted scientific contribution of both methodological and technological advances in the ways in which UAV's can be used in earth science and high mountain research as well as empirical knowledge regarding the regional hydrology of the Cordillera Blanca and more generally the tropical Andes. Through its focus on water availability this research has important implications for rural livelihoods and long-term hydrologic, energy, economic and development planning in Peru. This research also contributes to the growing field of UAV applications by pushing the engineering boundaries of this technology, opening up a range of future scientific opportunities in other areas.

Committee:

Bryan Mark, PhD (Advisor); Darla Munroe, PhD (Committee Member); Michael Durand, PhD (Committee Member); Liu Desheng, PhD (Committee Member)

Subjects:

Geography; Geomorphology; Hydrologic Sciences; Hydrology; Physical Geography; Remote Sensing; Robotics; Soil Sciences; Technology; Water Resource Management

Keywords:

Peru; glaciers; uav; uas; drone; unmanned aerial vehicle; mapping; soil moisture; Andes; hydrology; Cordillera Blanca; remote sensing; structure from motion; tvdi; mountains; water resources; global climate change; glaciology;

Stilson, Mona T.Multi-UAV Control: An Envisioned World Design Problem
Master of Science (MS), Wright State University, 2008, Human Factors and Industrial/Organizational Psychology MS
Predator Unmanned Aerial Vehicle assets are in high demand in the theater of operations for supporting the Global War on Terror and this demand is expected to increase. This work involved exploratory case study research into the envisioned world design problem of networked Predator multi-UAV control, as a candidate for meeting higher Predator sortie requirements without the need for a one for one increase in pilots. The concept involves the development of a potential new position for controlling multiple UAVs, called the Multi-Aircraft Manager (MAM). The goal was to analyze work requirements and develop representational models of the structure of this new work domain and develop an initial MAM display design representation (with a temporal emphasis) as a first hypothesis for an iterative program of evaluation and refinement. An additional goal was to discover and document, through this case study, what analysis methods explored helped to inform the design of the display representations. The MAM Tasking and Timeline Display was ecologically designed and mapped from the MAM cognitive work analysis (CWA) as a hypothesis of the work support the MAM will need to perform multi-aircraft management within a Global Unmanned Air System (UAS) work environment. This display includes timeline, status, and workload management vantages intended to complement the traditional geospatial map-based displays used by UAV pilots. This conceptual low fidelity display was used to both further the discussion of MAM among domain practitioners in a concrete way, enrich the work analysis, as well as to gather more display design requirements. The display concept served as an artifact to assist potential future users of MAM displays in envisioning the possibilities for supporting MAM. This is only the first step in an iterative program of evaluation and display refinement research needed for evolving the MAM vision concept and developing advanced human computer interface (HCI) displays in support of MAM.

Committee:

John Flach, PhD (Committee Chair); Valerie Shalin, PhD (Committee Member); Mark Draper, PhD (Committee Member)

Subjects:

Design

Keywords:

Cognitive Work Analysis; Cognitive Systems Engineering; Ecological Interface Design; Unmanned Aerial Vehicle; Multi-Aircraft Management; Multi-UAV Control; Human Computer Interface Design; Timeline Display

Marsh, William EricAn Initial Methodology For The Definition And Implementation Of Unmanned Aerial Vehicle Agent Behaviors
Master of Science in Engineering (MSEgr), Wright State University, 2007, Human Factors Engineering
In many current agent-based modeling systems, it is difficult for a domain-expert user to define and implement agent behaviors without possessing extensive programming knowledge. MUAVES is an existing simulation environment that serves as a research testbed for examining command and control issues with unmanned aerial vehicle (UAV) systems containing many vehicle agents. In its previous form, defining agent behaviors required knowledge of the C# programming language that some MUAVES users did not have. This thesis presents a new methodology for the definition and implementation of UAV agent behaviors in MUAVES. The new methodology is based on diagramming an agent’s controller state. No programming knowledge is required to reuse modular behaviors and trigger conditions specified by previous researchers. The definition of novel behaviors has also been improved by placing behavioral code in external library files, away from the main simulation code. These novel behaviors can be implemented at any desired level of abstraction. After describing the methodology, some sample scenarios are presented as proofs-of-concept.

Committee:

Raymond Hill (Advisor)

Keywords:

agent; behavior; implementation; definition; unmanned aerial vehicle; uav; methodology; muaves; abstraction; modeling