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An Evaluation Of A Low-Cost Uav Approach To Noxious Weed Mapping, Brandon Tyler Jones
An Evaluation Of A Low-Cost Uav Approach To Noxious Weed Mapping, Brandon Tyler Jones
Theses and Dissertations
Mapping their location and extent is a critical step in noxious weed management. One of the most common methods of mapping noxious weeds is to walk the perimeter of each patch with a handheld GPS receiver. This is the method used at Camp Williams, a National Guard Bureau training facility in Utah where this study was conducted. It was proposed that a low-cost Unmanned Aerial Vehicle (UAV) that made use of a hobbyist remote control airplane equipped with a Global Positioning System (GPS) receiver and digital camera could be used along with automated post-processing techniques to reduce the cost of …
Supporting Flight Control For Uav-Assisted Wilderness Search And Rescue Through Human Centered Interface Design, Joseph L. Cooper
Supporting Flight Control For Uav-Assisted Wilderness Search And Rescue Through Human Centered Interface Design, Joseph L. Cooper
Theses and Dissertations
Inexpensive, rapidly deployable, camera-equipped Unmanned Aerial Vehicle (UAV) systems can potentially assist with a huge number of tasks. However, in many cases such as wilderness search and rescue (WiSAR), the potential users of the system may not be trained as pilots. Simple interface concepts can be used to build an interaction layer that allows an individual with minimal operator training to use the system to facilitate a search or inspection task. We describe an analysis of WiSAR as currently accomplished and show how a UAV system might fit into the existing structure. We then discuss preliminary system design efforts for …
Adaptive Quaternion Control For A Miniature Tailsitter Uav, Nathan B. Knoebel
Adaptive Quaternion Control For A Miniature Tailsitter Uav, Nathan B. Knoebel
Theses and Dissertations
The miniature tailsitter is a unique aircraft with inherent advantages over typical unmanned aerial vehicles. With the capabilities of both hover and level flight, these small, portable systems can produce efficient maneuvers for enhanced surveillance and autonomy with little threat to surroundings and the system itself. Such vehicles are accompanied with control challenges due to the two different flight regimes. Problems with the conventional attitude representation arise in estimation and control as the system departs from level flight conditions. Furthermore, changing dynamics and limitations in modeling and sensing give rise to significant attitude control design challenges. Restrictions in computation also …
Decentralized Control Of Multiple Uavs For Perimeter And Target Surveillance, Derek B. Kingston
Decentralized Control Of Multiple Uavs For Perimeter And Target Surveillance, Derek B. Kingston
Theses and Dissertations
With the recent development of reliable autonomous technologies for small unmanned air vehicles (UAVs), the algorithms utilizing teams of these vehicles are becoming an increasingly important research area. Unfortunately, there is no unified framework into which all (or even most) cooperative control problems fall. Five factors that affect the development of cooperative control algorithms are objective coupling, communication, completeness, robustness, and efficiency. We classify cooperative control algorithms by these factors and then present three algorithms with application to target and perimeter surveillance and a method for decentralized algorithm design. The primary contributions of this research are the development and analysis …
Transitions Between Hover And Level Flight For A Tailsitter Uav, Stephen R. Osborne
Transitions Between Hover And Level Flight For A Tailsitter Uav, Stephen R. Osborne
Theses and Dissertations
Vertical Take-Off and Land (VTOL) Unmanned Air Vehicles (UAVs) possess several desirable characteristics, such as being able to hover and take-off or land in confined areas. One type of VTOL airframe, the tailsitter, has all of these advantages, as well as being able to fly in the more energy-efficient level flight mode. The tailsitter can track trajectories that successfully transition between hover and level flight modes. Three methods for performing transitions are described: a simple controller, a feedback linearization controller, and an adaptive controller. An autopilot navigational state machine with appropriate transitioning between level and hover waypoints is also presented. …
Particle Filter Based Mosaicking For Forest Fire Tracking, Justin Mathew Bradley
Particle Filter Based Mosaicking For Forest Fire Tracking, Justin Mathew Bradley
Theses and Dissertations
Using autonomous miniature air vehicles (MAVs) is a cost-effective, simple method for collecting data about the size, shape, and location characteristics of a forest fire. However, noise in measurements used to compute pose (location and attitude) of the on-board camera leads to significant errors in the processing of collected video data. Typical methods using MAVs to track fires attempt to find single geolocation estimates and filter that estimate with subsequent observations. While this is an effective method of resolving the noise to achieve a better geolocation estimate, it reduces a fire to a single point or small set of points. …
Development Of Deployable Wings For Small Unmanned Aerial Vehicles Using Compliant Mechanisms, Steven D. Landon
Development Of Deployable Wings For Small Unmanned Aerial Vehicles Using Compliant Mechanisms, Steven D. Landon
Theses and Dissertations
Unmanned Air Vehicles (UAVs) have recently gained attention due to their increased ability to perform sophisticated missions with less cost and/or risk than their manned counterparts. This thesis develops approaches to the use of compliant mechanisms in the design of deployable wings for small UAVs. Although deployable wings with rigid-link mechanisms have been used in the past to maintain flight endurance while minimizing required storage volume, compliant mechanisms offer many advantages in manufacturability and potential space savings due to function sharing of components. A number of compliant, deployable wing concepts are generated and a classification system for them is formed. …
Vision-Based Control And Flight Optimization Of A Rotorcraft Uav, David Christian Hubbard
Vision-Based Control And Flight Optimization Of A Rotorcraft Uav, David Christian Hubbard
Theses and Dissertations
A Rotorcraft UAV provides an ideal experimental platform for vision-based navigation. This thesis describes the flight tests of the US Army PALACE pro ject, which implements Moravec's pseudo-normalized correlation tracking algorithm. The tracker uses the movement of the landing site in the camera, a laser range, and the aircraft attitude from an IMU to estimate the relative motion of the UAV. The position estimate functions as a GPS equivalent to enable the rotorcraft to maneuver without the aid of GPS. Flight tests were performed with obstacles and over concrete, asphalt, and grass in daylight conditions with a safe landing area …
Panoramic Video For Efficient Ground Surveillance From Small Unmanned Air Vehicles, Joseph Aaron Jackson
Panoramic Video For Efficient Ground Surveillance From Small Unmanned Air Vehicles, Joseph Aaron Jackson
Theses and Dissertations
As unmanned air vehicle (UAV) utilization increases in Wilderness Search and Rescue (WiSAR) efforts, onboard sensors yielding more information will be desired. UAVs can assist WiSAR efforts by accelerating the ground search process through returning quality aerial footage of the terrain. Additionally, tracking the progress of a search by populating a digital map with video resolution data increases confidence that a comprehensive search of the region has been made. This thesis presents methods for acquiring video from multiple video sensors and fusing them into a single rendered video stream as a Virtual Gimbal. The panoramic video stream is the first …
Applications Of Search Theory To Coordinated Searching By Unmanned Aerial Vehicles, Steven R. Hansen
Applications Of Search Theory To Coordinated Searching By Unmanned Aerial Vehicles, Steven R. Hansen
Theses and Dissertations
Concepts in optimal search theory have been used in human-based aerial search since World War II. This thesis addresses the technical and theoretical issues necessary to apply this crucial theory to search path planning for Small Unmanned Aerial Vehicles (SUAVs). A typical search often requires that more than one target be located. Accordingly, a method is presented to locate multiple targets in three dimensions, as well as to differentiate between them. However, significant error can be present when locating targets from an airborne platform, and the idea of target quality is also introduced as a way to describe the reliability …
Development Of An Efficient Solar Powered Unmanned Aerial Vehicle With An Onboard Solar Tracker, Troy Dixon Tegeder
Development Of An Efficient Solar Powered Unmanned Aerial Vehicle With An Onboard Solar Tracker, Troy Dixon Tegeder
Theses and Dissertations
Methods were developed for the design of a solar powered UAV capable of tracking the sun to achieve maximum solar energy capture. A single-axis solar tracking system was designed and constructed. This system autonomously rotated an onboard solar panel to find the angle of maximum solar irradiance while the UAV was airborne. A microcontroller was programmed and implemented to control the solar tracking system. A solar panel and an efficient airframe capable of housing the solar tracking system was designed and constructed. Each of these subsystems was tested individually with either ground or flight tests. Ultimately, the final assembled system …
Feature-Based Mini Unmanned Air Vehicle Video Euclidean Stabilization With Local Mosaics, Damon Dyck Gerhardt
Feature-Based Mini Unmanned Air Vehicle Video Euclidean Stabilization With Local Mosaics, Damon Dyck Gerhardt
Theses and Dissertations
Video acquired using a camera mounted on a mini Unmanned Air Vehicle (mUAV) may be very helpful in Wilderness Search and Rescue and many other applications but is commonly plagued with limited spatial and temporal field of views, distractive jittery motions, disorienting rotations, and noisy and distorted images. These problems collectively make it very difficult for human viewers to identify objects of interest as well as infer correct orientations throughout the video. In order to expand the temporal and spatial field of view, stabilize, and better orient users of noisy and distorted mUAV video, a method is proposed of estimating …