Este trabalho apresenta os principais conceitos de um modelo de referência, chamado de Consciência Situacional em Voo (In-Flight Awareness, IFA), e sua implementação embarcada IFA2S (In-Flight Awareness Augmentation System). IFA é um conceito novo e realista e voltado à melhoria da segurança de voo de VANTs. IFA2S tem o potencial de alavancar confiabilidade dos VANTs aos níveis encontrados na aviação geral. Ele aumenta a consciência aeronave tanto em relação a si mesma e seu ambiente circundante e, ao mesmo tempo reconhece restrições da plataforma para agir de acordo com algoritmos de decisão pré-definidos. Este trabalho apresenta o IFA como consequência dos requisitos de segurança estabelecidos através da metodologia STPA, faz uma avaliação quantitativa do impacto do IFA2S no risco operacional dos VANTs e apresenta orientações de implementação em hardware. Simulações de validação são realizadas com uso do software Labview e do simulador de voo XPlane. / This work presents the key concepts of IFA, In-Flight Awareness, and its implementation IFA2S (In-Flight Awareness Augmentation System). IFA is a novel and realistic concept intended to enhance flight safety. IFA2S has the potential to leverage UAVs reliability to the levels of general aviation aircraft. It increases aircraft awareness regarding both itself and its environment and, at the same time recognizes platform constraints to act in accordance to predefined decision algorithms. This paper presents the IFA as a consequence of the safety requirements established using STPA methodology, a quantitative assessment of the impact of IFA2S in the operational risk of UAVs as well as suggestions for hardware implementation. Simulations are carried out using Labview software and the flight simulator XPlane.

Este projeto tem como objetivo a especicação de um enlace de comunicação digital para veículos aéreos não tripulados. Os principais desaos presentes no meio de transmissão serão evidenciados, assim como o impacto acarretado no sistema de comunicação. O projeto foi dividido entre a parte analógica e digital. A parte analógica tratará dos requisitos de potência para o devido funcionamento do canal através do procedimento de link budget. O projeto da parte digital, por sua vez, empregará a técnica de transmissão OFDM. No presente trabalho foi sugerido um método de estimação do canal utilizando os tons pilotos. O desempenho desta abordagem será medido através de uma simulação de monte Carlo / This project aims to design a digital data communication link for unmaned aerial vehicles. We will focus the main challenges and their impacts in the communication system. The project was divided in an analog and digital block. The analog block address the power requirements that make the system works by using a link budget procedure. The digital block will use the OFDM transmission technique. In this work we also suggest a channel estimation procedure via pilot tones. The performance of this approach will be measured by Monte Carlo Simulation

This work investigates the problem of transfer from simulation to the real world in the context of autonomous navigation. To this end, we first present a photo-realistic training and evaluation simulator (Sim4CV)* which enables several applications across various fields of computer vision. Built on top of the Unreal Engine, the simulator features cars and unmanned aerial vehicles (UAVs) with a realistic physics simulation and diverse urban and suburban 3D environments. We demonstrate the versatility of the simulator with two case studies: autonomous UAV-based tracking of moving objects and autonomous driving using supervised learning. Using the insights gained from aerial object tracking, we find that current object trackers are either too slow or inaccurate for online tracking from an UAV. In addition, we find that in particular background clutter, fast motion and occlusion are preventing fast trackers such as correlation filter (CF) trackers to perform better. To address this issue we propose a novel and general framework that can be applied to CF trackers in order incorporate context. As a result the learned filter is more robust to drift due to the aforementioned tracking challenges. We show that our framework can improve several CF trackers by a large margin while maintaining a very high frame rate. For the application of autonomous driving, we train a driving policy that drives very well in simulation. However, while our simulator is photo-realistic there still exists a virtual-reality gap. We show how this gap can be reduced via modularity and abstraction in the driving policy. More specifically, we split the driving task into several modules namely perception, driving policy and control. This simplifies the transfer significantly and we show how a driving policy that was only trained in simulation can be transferred to a robotic vehicle in the physical world directly. Lastly, we investigate the application of UAV racing which has emerged as a modern sport recently. We propose a controller fusion network (CFN) which allows fusing multiple imperfect controllers; the result is a navigation policy that outperforms each one of them. Further, we embed this CFN into a modular network architecture similar to the one for driving, in order to decouple perception and control. We use our photo-realistic simulation environment to demonstrate how navigation policies can be transferred to different environment conditions by this network modularity.

The spatial accuracy of points obtained from aerial laser scanning is most affected by the parameters of the GNSS receiver used, the IMU unit and the parameters of the flight itself. An important role is played by the accuracy of the so-called calibration, ie the determination of the transformation elements between the coordinate systems of the scanning unit itself, the IMU and the position of the phase center of the GNSS antenna. The diploma thesis deals with the calibration accuracy of the IMU / GNSS unit. It compares the displacements and rotations of a point cloud acquired by LiDAR (laser scanner RIEGL miniVUX-1UAV) in relation to the calibration elements given by the manufacturer. Evaluate the results using calculated standard deviations and positional differences in the raw point cloud, or by comparing point clouds obtained by another method. It also focuses on verifying geometric accuracy using checkpoints. The accuracy of the IMU / GNSS calibration is minimal after verifying the results and comparing the influence of the calibration elements given by the manufacturer. There was no significant improvement in the quality of the point cloud. At the same time, it was found that for better quality of the scanned data, it is necessary to perform cross-flights when UAV scanning. Key words UAV,...

Topographic mapping of rock formations using GIS methods Abstract This thesis deals with issues of creating 3D models of rock formations with data from terrestrial laser scanning, close range photogrammetry and UAV photogrammetry. The theoretical part focuses on explaining functioning and usage of those methods. Beside that there is described issues of 3D point cloud filtering. Practical part of this work describes data collecting and processing procedure. Further there is proposed filtering process which aim to remove noise points from point clouds and remove vegetation with combination of vegetation index ExG, clustering algorithm DBSCAN and Hough Transform. The proposed method is tested on the selected rock formation in Bohemian Switzerland National Park. The evaluation of the proposed method is based on comparison of models filtered with proposed method with reference models, which are filtered manually. Finally, the achieved accuracy of the models is evaluated using geodetic measurements. key words laser scanning, photogrammetry, UAV, point cloud, data filtering

Cooperative control for miniature air vehicles (MAVs) is currently a highly researched topic. There are many application for which MAVs are well suited, including fire monitoring, surveillance and reconaissance, and search and rescue missions. All of these applications can be carried out more effictively by a team of MAVs than by a single vehicle. As technologies for microcontrollers and small sensors have improved so have the capabilities of MAVs. This improvement in MAV performance abilities increases the possibility for cooperative missions. The focus of this research was on cooperative timing missions. The issues faced when dealing with multi-MAV flight include information transfer, real time path planning, and maintenance of a fleet of flight-worthy MAVs. Additional challenges associated with timing missions include path following and velocity control. Two timing scenarios were studied and both of these scenarios were flight tested. The first scenario was a sequenced arrival of the MAVs over a target at a predetermined fly-through heading. The second scenario was a simultaneous arrival of the team ofMAVs over a known target location. The ideas of coordination functions and coordination variables have been employed to achieve coordination. Experimental results verify the feasibility of real time coperative control for a team of MAVs. Initial cooperative timing tests revealed the need for more accurate path following. Accordingly, a new method for path following using vector fields was developed. A vector field of desired ground track headings is calculated and commanded ground track headings are calculated such that ground track heading error and lateral following error decay asymptotically even in the presence of constant wind disturbances. The utilization of ground track heading and ground speed in the path following control, in combination with the vector field methods is what makes this zero-error following possible. Methods for following straight lines and orbits as well as combinations of the lines and circular arcs are presented. The assertions that minimal following errors result when using these methods have been verified experimentally.

The control of multiple unmanned aerial vehicles (UAVs) in a swarm or cooperative team scenario has been a topic of great interest for well over a decade, growing steadily with the advancements in UAV technologies. In the academic community, a majority of the studies conducted rely on simulation to test developed control strategies, with only a few institutions known to have nurtured the infrastructure required to propel multiple UAV control studies beyond simulation and into experimental testing. With the Cal Poly UAV FLOC Project, such an infrastructure was created, paving the way for future experimentation with multiple UAV control systems. The control system architecture presented was built on concepts developed in previous work by Cal Poly faculty and graduate students. An outer-loop formation flight controller based on a virtual waypoint implementation of potential function guidance was developed for use on an embedded microcontroller. A commercially-available autopilot system, designed for fully autonomous waypoint navigation utilizing low cost hardware and open source software, was modified to include the formation flight controller and an inter-UAV communication network. A hardware-in-the-loop (HIL) simulation was set up for multiple UAV testing and was utilized to verify the functionality of the modified autopilot system. HIL simulation results demonstrated leader-follower formation convergence to 15 meters as well as formation flight with three UAVs. Several sets of flight tests were conducted, demonstrating a successful leader-follower formation, but with relative distance convergence only reaching a steady state value of approximately 35 +/- 5 meters away from the leader.

Metody, jak získat zpět měřicí vybavení pro průzkum horní atmosféry, jsou v současné době značně omezené. Velmi nízká míra návratnosti vedla k návrhu radiosondy na jedno použití, což nutí mnoho světových meteostanic omezit počet provedených denních měření. Snížení frekvence sondáže pak následně vede ke snížení přesnosti předpovědi počasí. Tato práce otevírá cestu k alternativě v podobě konstrukce návratového modulu, který by měl zajistit řízené vyklesání aerologické sondy a přistání na vhodném místě. Zvolená konstrukce je výsledkem analýzy možných konfigurací, jejichž cílem bylo najít nejoptimálnější variantu pro splnění požadavků mise. Konvenční konfigurace s pevnými křídly je zde sledována zkoumáním jejích základních částí. Zvolené součásti jsou dimenzovány na základě dvou krokových iteračních metod detailně popsaných v této práci. Dále jsou zkoumány základní požadavky na autonomii návratového kluzáku. Je zde navržena koncepce řídicího systému, který by měl vybrat nejvhodnější a dostupné místo pro přistání a navést kluzák k přistání na něm. V neposlední řadě jsou analyzovány a zvažovány možné metody instalace užitečného zatížení a studovány a porovnávány možné systémy odpojení od meteorologického balónu. Popsaný návratový modul by měl ve výsledku umožnit častější provádění měření atmosféry s přesnějšími měřicími zařízeními u kterých bude předpoklad vysoké pravděpodobnosti opakovaného použití. Očekává se, že tento přístup by měl vést ke snížení nákladů na sondáž atmosféry a zároveň zredukovat množství použitého materiálu a produkovaného odpadu.

Computational Fluid Dynamics has become a versatile product development tool, bringing many advantages to the conceptual design phase of products, and is being used for a wide variety of applications. In this thesis, the aerodynamics of a UAV with internal radar has been investigated. UAV is an acronym for Unmanned Aerial Vehicle, that is an aircraft which is flown with no human pilot onboard the aircraft, maneuvering the flight controls. The studies conducted throughout this thesis aimed at conducting numerical simulations of two UAV wing designs, through the utilization of the Vortex Lattice Method and Computational Fluid Dynamics. A number of different flight cases were investigated for comparing the two wing designs with respect to their aerodynamic characteristics, as well as a sustained turn analysis for the second UAV wing design. The analyses were conducted by importing provided UAV CAD-models into the numerical software, setting up appropriate grids, and running the simulations at the flight cases of interest. The results gathered from the simulations concerning the first wing design demonstrated favorable flight characteristics at lower angles of attack, although at angles of attack greater than 5°, flow separation was apparent. Regarding the results concerning the second wing design, it could be flown at greater angles of attack without experiencing flow separation, while decreasing the total drag of the UAV. For the sustained turn analysis concerning the second wing design, the aircraft generated sufficient lift at desired load factors, for maintaining its altitude however, it could not reach a trimmed state despite larger deflection angles of the ruddervators. Therefore the center of gravity position of the UAV was manipulated for sustaining the turns at desired load factors. Pressure contour plots were generated from the CFD simulations from which it could be determined that the front and nose of the aircraft could be further redesigned for decreasing aerodynamic drag.

Unmanned Air Vehicles (UAVs) enable the observation of hazardous areas without endangering a pilot. Observational capabilities are provided by on-board video cameras and images are relayed to remote operators for analysis. However, vibration and wind cause video camera mounts to move and can introduce unintended motion that makes video analysis more difficult. Video stabilization is a process that attempts to remove unwanted movement from a video input to provide a clearer picture. This thesis presents an onboard video stabilization solution that removes high-frequency jitter, displays output at 20 frames per second (FPS), and runs on a Blackfin embedded processor. Any video stabilization algorithm will have to contend with the limited space, weight, and power available for embedded systems hardware on a UAV. This thesis demonstrates how architecture-specific optimizations improve algorithm performance on embedded systems and allow an algorithm that was designed with more powerful computing systems in mind to perform on a system that is limited in both size and resources. These optimizations reduce the total clock cycles per frame by 157 million to 30 million, which yields a frame rate increase from 3.2 to 20 FPS.