Through out history, technological advancements have reshaped the built environment and its Architecture. The cities that we live in today were only made possible by the technologies of the first, second, and third industrial revolutions. Today, we are witnessing another technological revolution based on open source data and artificial intelligence. As there is an enormous amount of prosperous innovations that would directly impact Architecture design tools, building and finishing materials, and construction methods, there are also other innovations that would require spaces, buildings, and cities to be designed to accommodate them. Among the latter mentioned innovations is the Unmanned Aerial Vehicle (UAV), also know as drones. Like the automobile, drone technology will influence not only the way we live but also our design thinking and the components of our built environment. Along with drone's ability to fly, UAV's digital infrastructure is much more flexible and most importantly, invisible. Autonomous Drones' intelligent abilities allow them to provide a wide range of services in various fields such as; freight and delivery, transportation, infrastructure and buildings maintenance, survey, surveillance, policing, fire fighting, agriculture, and even construction, all of which will effectively reduce the amount of ground vehicle traffic, especially in populated cities. Today, as these possibilities are available and constantly under development, it is important for Architecture and Urban Design disciplines to address the challenge and provide comprehensive solutions to accommodate such a technology and allow its possibilities to prosper even further. The intent of this thesis is to study UAV technology and design a mix-use complex that embraces and accommodates UAV services such as; delivery, transport, freight, and maintenance. The complex hosts a residential tower, a vertical garden tower, ground level commercial spaces, and an underground drone hub. / Master of Architecture / Today, we are witnessing another technological revolution based on open source data and artificial intelligence. As there is an enormous amount of prosperous innovations that would directly impact architecture design tools, building and finishing materials, and construction methods, there are also other innovations that would require the built environment of our cities to be designed to accommodate them. Among the later mentioned innovations is the Unmanned Aerial Vehicle (UAV), also known as drones. Autonomous drones are flying robots with intelligent abilities which allow them to provide a wide range of services in various fields such as; freight and delivery, transportation, infrastructure and buildings maintenance, survey, surveillance, policing, fire fighting, agriculture, and even construction, all of which will are available today and constantly under development. Therefore, it is important for architecture and urban design disciplines to address the challenge and provide comprehensive solutions to accommodate such a technology and allow it to grow even further. The intent of this thesis is study drones and their future possibilities and to design a mixed-use complex that embraces and accommodates drone services such as; delivery, transport, freight, and maintenance. The complex hosts a residential tower, a vertical garden tower, ground level commercial spaces, and an underground drone hub.

Unmanned aerial vehicles (UAVs) are increasingly being used for both military and commercial applications to replace more costly and dangerous manned operations. Vehicles with vertical take-off and landing (VTOL) and hovering capabilities are of interest for functions such as surveillance and inspection where the ability to hold the position of the vehicle is desired. Ducted fan vehicles are of particular interest because of their high efficiency per unit diameter when compared to the more commonly seen multirotor vehicles. This makes ducted fan UAVs very well suited for size-constrained missions such as indoor inspection or urban reconnaissance. However, the advantages of ducted fans come at the cost of complex nonlinear dynamics which present challenging modeling and control problems. This thesis provides a detailed discussion of the instrumentation, modeling, and control of a ducted fan UAV. The dynamic model of the UAV is computed from a simplified parametric model. Unknown parameters of the model are found from system identification based on flight data. Synthesis of a linear state feedback controller based on this model is discussed, and it is demonstrated in hardware that this controller can effectively stabilize the vehicle. / Master of Science / Unmanned aerial vehicles (UAVs) are increasingly being used for both military and commercial applications to replace more costly and dangerous manned operations. Vehicles with vertical take-off and landing (VTOL) and hovering capabilities are of interest for functions such as surveillance and inspection where the ability to hold the position of the vehicle is desired. Ducted fan vehicles are of particular interest because of their high efficiency per unit diameter when compared to the more commonly seen multirotor vehicles. This makes ducted fan UAVs very well suited for size-constrained missions such as indoor inspection or urban reconnaissance. However, the advantages of ducted fans come at the cost of complex dynamics which present challenging modeling and control problems. This thesis provides a detailed discussion of the instrumentation, modeling, and control of a ducted fan UAV. The dynamic model of the UAV is computed from a simplified parametric model. Unknown parameters of the model are found from system identification based on flight data. Using this parametric model, development of a linear controller that uses feedback from the vehicle’s state is discussed, and it is demonstrated in hardware that this controller can effectively stabilize the vehicle.

In order to operate UAVs under human supervisory control in more complex arenas such as urban environments, an obstacle detection system is a requirement to achieve safe navigation. The development of a system capable of meeting these requirements is presented. The first stage of development was sensor selection and initial testing. After this, the sensor was combined with a servomotor to allow it to rotate and provide obstacle detection coverage in front, below, and to both sides of the UAV. Utilizing a PC-104 single board computer running LabView Real-time for on-board control of the sensor and servomotor, a stand alone obstacle detection system was developed meeting the requirements of light weight, low power, and small size. The detection performance of the system for several parameters has been fully characterized. A human subjects study was conducted to assess the any advantages resulting from the addition of the obstacle detection system compared to that of a normal nadir camera. The study demonstrated that users with access to the three-dimensional display were able to navigate an obstacle course with greater success than those with only a camera. Additional development into more advanced visualization of the environment has potential to increase effectiveness of this obstacle detection system. / Master of Science

When considering the operation of an Unmanned Aerial Vehicle (UAV) or an Unmanned Ground Vehicle (UGV), such problems as landing site estimation or robot path planning become a concern. Deciding if an area of terrain has a level enough slope and a wide enough area to land a Vertical Take Off and Landing (VTOL) UAV or if an area of terrain is traversable by a ground robot is reliant on data gathered from sensors, such as cameras. 3-D models, which can be built from data extracted from digital cameras, can help facilitate decision making for such tasks by providing a virtual model of the surrounding environment the system is in. A stereo vision system utilizes two or more cameras, which capture images of a scene from two or more viewpoints, to create 3-D point clouds. A point cloud is a set of un-gridded 3-D points corresponding to a 2-D image, and is used to build gridded surface models. Designing a stereo system for distant terrain modeling requires an extended baseline, or distance between the two cameras, in order to obtain a reasonable depth resolution. As the width of the baseline increases, so does the flexibility of the system, causing the orientation of the cameras to deviate from their original state. A set of tools have been developed to generate 3-D point clouds from rigid and flexible stereo systems, along with a method for applying corrections to a flexible system to regain distance accuracy in a flexible system. / Master of Science

There is a growing interest in agricultural spray drone (ASD) use for herbicide application in managed turfgrass systems, which historically has precluded aerial application. Considering pesticide deposition accuracy is of utmost importance in managed turfgrass systems, a thorough examination of factors that influence ASD spray deposition patterns is needed. A python-based spray deposition pattern analysis tool, SprayDAT, was developed to estimate spray quality utilizing a cost-effective continuous sampling technique involving digital soand spectrophotometric analysis of blue colorant stains on white Kraft paper. This technique cost 0.2 cents per USD spent on traditional water-sensitive paper (WSP) allowing for continuous sampling necessary for the highly variable deposition patterns delivered by an ASD. SprayDAT conserved droplet densities and more accurately detected stain objects compared to a commonly utilized software, DepositScan, which overestimated stain sizes. However, droplet density exhibited an upper asymptote at 22% stain cover when relating volume median diameter (VMD) due to increasing overlap of stain objects. Spread factor of blue colorant stains was fit to a 2-parameter power equation when compared across six discrete droplet sizes between 112 and 315 µm when droplets were captured in a biphasic solution of polydimethylsiloxane of 100 cSt over 12,500 cSt viscosities. Cumulative digitally assessed stain objects underestimated application volume 270% when compared to the predicted output based on flow rate, coverage, and speed. SprayDAT incorporates a standard curve based on colorant extraction and spectrophotometric analysis to correct this error such that total stain area accurately estimates application volume to within 9%. This relationship between extracted colorant and total stain area, however, is dependent on droplet size spectra. SprayDAT allows users to customize standard curves to address this issue. Using these analysis techniques, continuous sampling of a 29.3-m transect perpendicular to an ASD or ground sprayer spray swath resolved that increasing ASD operational height increases drift and effective swath width while effective application rate, total deposition, and smooth crabgrass control by quinclorac herbicide decreases. Deposition under the ASD was heterogeneous as the coefficient of variation (CV) within the targeted swath exceeded 30% regardless of operational height. At higher operational heights, relative uniformity of spray pattern was improved but droplet density at 11.7 m away from the intended swath edge was up to four times greater and total spray deposited was up to 60% reduced at the highest heights. For each 1-m increase in ASD operational height, 6% of the deposited spray solution, 11% of the effective application rate within the targeted swath, and 7% of smooth crabgrass [Digitaria ischaemum (Schreb.) Schreb. ex Muhl.] population reduction declined. Subsequent studies suggested that total deposition loss with increasing operational height of ASD were likely due to droplet evaporation. Discrete-sized droplets subjected to a 5-m fall in a windless environment exhibited a sigmoidal relationship where 98% volume of 135-µm droplets and approximately 67% volume of 177 – 283 µm diameter droplets evaporated. Addition of drift reduction agents (DRAs) or choosing different nozzle types altered the initial droplet density generated by a flat-fan nozzle. Regardless of DRA additions or nozzle replacement, the distance required to lose 50% of small droplets (< 150 µm diameter) was 6.6 m. Air induction nozzles and DRA admixtures also conserved smooth crabgrass control across 2- and 6-m operational heights, where control was reduced at the 6-m height with a flat fan nozzle without DRA. Spray deposition pattern analysis for multipass ASD and ground applications was conducted by utilizing nighttime UV-fluorescence aerial photography and weed infestation counts in a digitally overlaid grid. Results show that under-application across all devices was consistent and averaged 12%, whereas at least 14% more over-application on the targeted area was observed for ASD, regardless of equipped nozzle types, compared to a ride-on sprayer. Drift also occurred at least 3 times more for ASD application than for a ride-on sprayer and a spray gun sprayer. Using smooth crabgrass infestation annotated from aerial images could not consistently resolve the spatial variability evident in UV-fluorescent imagery presumably due to the innate variability in weed populations. Analysis using SprayDAT revealed insights into factors affecting ASD spray deposition, such as operational height impacting drift, effective swath width, and herbicide efficacy, highlighting the tool's utility in optimizing aerial herbicide applications in turfgrass management. Data suggest that the lowest ASD operational height should be employed to partially mitigate drift and droplet evaporation while improving weed control. Lower operational heights, however, reduce effective swath width and increase heterogeneity of the deposition pattern. Future research should evaluate possible engineering controls for these problems. / Doctor of Philosophy / In recent years, there has been growing interest in using agricultural spray drones (ASD) for applying herbicides in managed turfgrass systems. Traditionally, aerial spraying has not been widely used in these settings, but ASDs are gaining attention. However, there is still a need for a better understanding of how different factors affect spray patterns of ASDs and weed control effectiveness. To address this, novel image analysis software, SprayDAT was developed. It uses white Kraft paper and blue colorant to analyze spray patterns. Compared to traditional methods, SprayDAT provides a cost-effective way to study spray deposition over larger areas, which is important for analyzing the irregular patterns produced by ASDs. The tool showed similar accuracy in detecting spray patterns compared to existing software used with water-sensitive papers, but with some improvements in detecting fine details. SprayDAT was used to analyze spray patterns from ASDs equipped with different nozzles at various heights, as well as ground application methods. It was found that regardless of height, ASDs showed some inconsistency in spray deposition, with about 6% of the spray solution and 11% of the effective application rate being lost for each 1-m increase in ASD height. This loss is likely due to droplet evaporation based on additional laboratory and field studies that directly measured droplet volume loss or stains of small droplets on white paper. In another part of the study, UV-fluorescent nighttime aerial images and weed infestation following herbicide sprays were used to assess spray deposition of multipass ASD applications. It was found that ASDs tended to over-apply in more of the targeted area than ground-based methods and caused more drift of spray to non-target areas. These studies suggest that lower operational heights, such as 2-m above ground, is recommended when controlling weeds with an ASD as effective application rate and weed control will be improved. These low heights, however, increase variability of rate across the intended spray swath and reduce the effective swath width.

Thesis (MScEng (Electrical and Electronic Engineering))--University of Stellenbosch, 2010. / ENGLISH ABSTRACT: This thesis presents the development of a stall prevention flight control subsystem, which can easily be integrated into existing flight control architectures of fixed-wing unmanned aerial vehicles (UAV’s). This research forms an important part of faulttolerant flight control systems and will ensure that the aircraft continues to operate safely within its linear aerodynamic region. The focus of this thesis was the stall detection and prevention problem. After a thorough literature study on the topic of stall, a model based stall prevention control algorithm with feedback from an angle of attack sensor was developed. This algorithm takes into account the slew rate and saturation limits of the aircraft’s servos and is able to predict when the current flight condition will result in stall. The primary concern was stall during wings-level flight and involved the prevention of stall by utilising only the elevator control surface. A model predictive slew rate control algorithm was developed to override and dynamically limit the elevator command to ensure that the angle of attack does not exceed a predefined limit. The stall prevention control system was designed to operate as a switching control scheme, to minimise any restrictions imposed on the existing flight control system. Finally, software in the loop simulations were conducted using a nonlinear aircraft model and realistic sensor noise, to verify the theoretical results obtained during the development of this stall prevention control strategy. A worst-case performance analysis was also conducted to investigate the robustness of the control algorithms against model uncertainties. / AFRIKAANSE OPSOMMING: Hierdie tesis handel oor die ontwikkeling van ’n staak voorkomings-vlugbeheer substelsel wat maklik geïntegreer kan word in bestaande vlugbeheer argitektuur van onbemande vaste-vlerk lugvaartuie. Hierdie tesis vorm ’n belangrike deel van fouttolerante vlugbeheertegnieke en sal verseker dat die vliegtuig slegs binne sy lineêre aerodinamiese werksgebied bly. Die fokus van hierdie tesis is die staak opsporing en voorkomings probleem. Na afloop van ’n deeglike literatuurstudie oor die onderwerp van staak, is ’n model gebaseerde staak voorkomings-beheertegniek ontwikkel, wat terugvoer van ’n invalshoek sensor ontvang. Hierdie algoritme neem die sleur tempo en defleksie limiete van die vliegtuig se servos in ag en is in staat om staak te voorspel. Die primêre oorweging was staak tydens simmetriese vlugte en behels slegs die voorkoming van staak deur gebruik te maak van die hei beheer oppervlak. ’n Model voorspellings sleur tempo beheeralgoritme is ontwikkel om die hei-roer dinamies te beperk sodat die invalshoek nie ’n sekere vooraf bepaalde limiet oorskry nie. Die staak voorkomings beheerstelsel is ontwerp om te funksioneer as ’n skakel beheer skema om die beperkings op die bestaande vlugbeheerstelsel te minimaliseer. Laastens was sagteware-in-die-lus simulasies gebruik om die teoretiese resultate, wat verkry is tydens die ontwikkeling van hierdie staak voorkomings beheer-strategie, te kontroleer. Om die robuusthied van hierdie beheeralgoritmes teen model onsekerhede te ondersoek, is ’n ergste-geval prestasie analise ook uitgevoer.

Energetic limitations in low scale Unmanned Aerial Vehicles (UAVs) sometimes turns outdoor field applications impractical, which restricts the realization of several tasks that could potentially be improved or benefited from its sounding characteristics. Depending on the mission, Mini Aerial Vehicles (MAVs) energetic resources may be mostly wasted during the round trip from launching base and target point around which a given mission must be accomplished. In this sense, the initial deployment problem becomes prominent, raising new opportunities on how aerial robots may be launched/deployed. This work presents a novel perspective in morphological adaptations for aerial robotics that may potentially minimize initial deployment problem issues. From that perspective, we present three novel morphologies. First refers to a hybrid fixed-wing/quadrotor aiming in-flight launching possibilities. Still looking at in-flight launching, second MAV regards to a new morphology for a quadrotor whose center of gravity is shifted in order to improve passive static stability. Third one relates to a hybrid MAV that combines a watercraft and a quadrotor. The aircraft may navigate on water with low energetic cost through a specially designed structure. It also presents static stability in air and over the ground. We present all details concerning new concepts, development, analysis, design and flight simulation for all three novel platforms. A concise and robust validation of stability control is firstly performed with the &#169;VICON vision system. Finally, on-the-field evaluation for all three morphologies are extensively carried out, presenting optimistic experimental results of our findings. / As limitações energéticas em robótica aérea de campo muitas vezes levam à sua não utilização em tarefas que poderiam se beneficiar substancialmente de suas inúmeras vantagens. Dependendo da complexidade da missão, os recursos energéticos podem ser despendidos prematuramente ainda durante o traslado ao ponto de interesse. Nesse contexto, se evidencia o problema do lançamento inicial de robôs, o que faz surgir novas possibilidades para o desenvolvimento de novas maneiras de lançá-los. Este trabalho propõe uma nova perspectiva para adaptações morfológicas para robótica aérea as quais podem significativamente minimizar os efeitos das limitações energéticas. Sob essa ótica, são propostas três novas morfologias. A primeira consiste de um robô aéreo híbrido asa fixa/quadrotor visando a possibilidade do lançamento em voo. A segunda consiste de uma aeronave de asa rotativa na configuração quadrotora morfologicamente adaptada para reposicionamento do seu centro de gravidade. O aumento da estabilidade estática passiva da aeronave também visa o seu lançamento durante o voo. A terceira se refere a um veículo aéreo híbrido que combina uma estrutura naval e um quadrotor, capaz de navegar em cenários aquáticos com baixo custo energético. O desenho mecânico resultante permite sua operação no ponto ótimo tanto para a navegação aérea quanto aquática, oferecendo estabilidade estática em todos os cenários (terra, ar e água). São apresentados todos os detalhes de conceito, concepção, análise, projeto e simulação em voo das três novas plataformas. Uma validação robusta dos sistemas de controle e estabilidade é realizada por sistema de visão ©VICON. Por fim, ensaios em campo são realizados, apresentando resultados experimentais otimistas para a aplicação das três novas morfologias.

Thesis--School of Advanced Airpower Studies, 1996. / Shipping list no.: 1998-0921-M. "August 1997." Includes bibliographical references. Also available via Internet from the Air University Press web site. Address as of 11/3/03: http://aupress.au.af.mil/SAAS%5FTheses/Renehan/renehen.pdf; current access is available via PURL.

Thesis (M.S.)--School of Advanced Air and Space Studies, 2008. / "June 2008." Vita. Includes bibliographical references (p. 125-131). Also available via the Internet.

Thesis (MScEng (Electrical and Electronic Engineering))--University of Stellenbosch, 2011. / ENGLISH ABSTRACT: Search and Rescue is an essential service provided by States and Militaries to search for, locate and rescue survivors of accidents and incidents. Civil Search and Rescue utilizes a system of well-trained professionals or volunteers, an effective Search and Rescue organization, supported by industry and other providers of infrastructure and assets. The service is rendered to save the lives of civilian individuals in imminent danger of losing their lives. Military (Combat) Search and Rescue is provided by militaries to save the lives of military practitioners in a similar predicament. In addition, Search and Rescue is performed over land and over the sea. All forms of Search and Rescue rely on capable, specialized assets for efficiency en affectivity. Assets are specified and chosen on the grounds of various factors, amongst others operating environment, operational profile, performance and special abilities. This thesis has determined the need for a Search and Rescue asset, capable of performing effective and efficient Search and Rescue over the entire national maritime Search and Rescue Region, up to the Region extremities. An analysis was performed to prove this deficit, and quantify the key performance and special equipment requirements for such an asset. An analysis was also performed which proves that an Unmanned Aircraft System should be an ideal choice to meet this need. Finally, an Unmanned Aircraft System concept was specified that could potentially meet this need. / AFRIKAANSE OPSOMMING: Soek en Redding is ‘n essentiële diens wat deur State en militêre organisasies gebied word om oorlewendes van ongelukke en insidente te soek, op te spoor en na veiligheid te bring. Siviele Soek en Redding maak gebruik van ‘n stelsel van goedopgeleide professionele persone, sowel as vrywilligers, asook ‘n effektiewe Soek en Reddingsorganisasie, ondersteun deur die industrie en ander voorsieners van infrastruktuur en toerusting. Derglike dienste word daargestel om die lewens van siviele persone, wie se lewens in gevaar is, te red. Militêre Soek en Redding word deur militêre organisasies daargetel om die lewens van militêre persone, wie in gevaar is, te red. Soek en Redding word oor land sowel as oor die see uitgevoer. Alle vorms van Soek en Redding maak staat op die beskikbaarheid van gespesialiseerde toerusting met gespesialiseerde gebruiksaanwending, vir maksimale effektiwiteit en doeltreffendheid. Toerusting word gekies op grond van verskeie faktore, onder meer die gebruiksomgewing, operasionele profiele, verlangde prestasie en spesiale vermoëns. Hierdie tesis het die behoefte aan ‘n gespesialiseerde Soek en Redding platform, wat die vermoë het om effektiewe en doeltreffende Soek en Redding uit te voer oor die hele nationale Soek en Redding Gebied, tot en met die ekstreme daarvan, vasgestel. ‘n Analise is uitgevoer om hierdie tekortkoming uit te wys, asook om die sleutel prestasie- en gespesialiseerde toerustingbehoeftes vir so ‘n platform te kwantifiseer. ‘n Verdere analise is uitgevoer om te bewys dat ‘n Onbemande Vliegtuig die beste opsie sou wees vir ‘n platform om aan hierdie behoeftes te voldoen. Ten slotte is ‘n konsep vir ‘n Onbemande Vliegtuig Stelsel voorgetsel wat potensieël hierdie behoefte sou kon vervul.