Autonomous, Collaborative, Unmanned Aerial Vehicles for Search and Rescue

Search and Rescue is a vitally important subject, and one which can be improved through the use of modern technology. This work presents a number of advances aimed towards the creation of a swarm of autonomous, collaborative, unmanned aerial vehicles for land-based search and rescue. The main advances are the development of a diffusion based search strategy for route planning, research into GPS (including the Durham Tracker Project and statistical research into altitude errors), and the creation of a relative positioning system (including discussion of the errors caused by fast-moving units). Overviews are also given of the current state of research into both UAVs and Search and Rescue

Zero-delay source-channel coding

In this thesis, we investigate the zero-delay transmission of source samples over three different types of communication channel models. First, we consider the zero-delay transmission of a Gaussian source sample over an additive white Gaussian noise (AWGN) channel in the presence of an additive white Gaussian (AWG) interference, which is fully known by the transmitter. We propose three parameterized linear and non-linear transmission schemes for this scenario, and compare the corresponding mean square error (MSE) performances with that of a numerically optimized encoder, obtained using the necessary optimality conditions. Next, we consider the zero-delay transmission of a Gaussian source sample over an AWGN channel with a one-bit analog-to-digital (ADC) front end. We study this problem under two different performance criteria, namely the MSE distortion and the distortion outage probability (DOP), and obtain the optimal encoder and the decoder for both criteria. As generalizations of this scenario, we consider the performance with a K-level ADC front end as well as with multiple one-bit ADC front ends. We derive necessary conditions for the optimal encoder and decoder, which are then used to obtain numerically optimized encoder and decoder mappings. Finally, we consider the transmission of a Gaussian source sample over an AWGN channel with a one-bit ADC front end in the presence of correlated side information at the receiver. Again, we derive the necessary optimality conditions, and using these conditions obtain numerically optimized encoder and decoder mappings. We also consider the scenario in which the side information is available also at the encoder, and obtain the optimal encoder and decoder mappings. The performance of the latter scenario serves as a lower bound on the performance of the case in which the side information is available only at the decoder.Open Acces

Performance Optimization of Memory Intensive Applications on FPGA Accelerator

L'abstract è presente nell'allegato / the abstract is in the attachmen

Navigation, Path Planning, and Task Allocation Framework For Mobile Co-Robotic Service Applications in Indoor Building Environments

Recent advances in computing and robotics offer significant potential for improved autonomy in the operation and utilization of today’s buildings. Examples of such building environment functions that could be improved through automation include: a) building performance monitoring for real-time system control and long-term asset management; and b) assisted indoor navigation for improved accessibility and wayfinding. To enable such autonomy, algorithms related to task allocation, path planning, and navigation are required as fundamental technical capabilities. Existing algorithms in these domains have primarily been developed for outdoor environments. However, key technical challenges that prevent the adoption of such algorithms to indoor environments include: a) the inability of the widely adopted outdoor positioning method (Global Positioning System - GPS) to work indoors; and b) the incompleteness of graph networks formed based on indoor environments due to physical access constraints not encountered outdoors. The objective of this dissertation is to develop general and scalable task allocation, path planning, and navigation algorithms for indoor mobile co-robots that are immune to the aforementioned challenges. The primary contributions of this research are: a) route planning and task allocation algorithms for centrally-located mobile co-robots charged with spatiotemporal tasks in arbitrary built environments; b) path planning algorithms that take preferential and pragmatic constraints (e.g., wheelchair ramps) into consideration to determine optimal accessible paths in building environments; and c) navigation and drift correction algorithms for autonomous mobile robotic data collection in buildings. The developed methods and the resulting computational framework have been validated through several simulated experiments and physical deployments in real building environments. Specifically, a scenario analysis is conducted to compare the performance of existing outdoor methods with the developed approach for indoor multi-robotic task allocation and route planning. A simulated case study is performed along with a pilot experiment in an indoor built environment to test the efficiency of the path planning algorithm and the performance of the assisted navigation interface developed considering people with physical disabilities (i.e., wheelchair users) as building occupants and visitors. Furthermore, a case study is performed to demonstrate the informed retrofit decision-making process with the help of data collected by an intelligent multi-sensor fused robot that is subsequently used in an EnergyPlus simulation. The results demonstrate the feasibility of the proposed methods in a range of applications involving constraints on both the environment (e.g., path obstructions) and robot capabilities (e.g., maximum travel distance on a single charge). By focusing on the technical capabilities required for safe and efficient indoor robot operation, this dissertation contributes to the fundamental science that will make mobile co-robots ubiquitous in building environments in the near future.PHDCivil EngineeringUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttps://deepblue.lib.umich.edu/bitstream/2027.42/143969/1/baddu_1.pd

A two-dimensional adaptive-wall test section with ventilated walls in the Ames 2- by 2-foot transonic wind tunnel

The first tests conducted in the adaptive-wall test section of the Ames Research Center's 2- by 2-Foot Transonic Wind Tunnel are described. A procedure was demonstrated for reducing wall interference in transonic flow past a two-dimensional airfoil by actively controlling flow through the slotted walls of the test section. Flow through the walls was controlled by adjusting pressures in compartments of plenums above and below the test section. Wall interference was assessed by measuring (with a laser velocimeter) velocity distributions along a contour surrounding the model, and then checking those measurements for their compatibility with free-air far-field boundary conditions. Plenum pressures for minimum wall interference were determined from empirical influence coefficients. An NACA 0012 airfoil was tested at angles of attach of 0 and 2, and at Mach numbers between 0.70 and 0.85. In all cases the wall-setting procedure greatly reduced wall interference. Wall interference, however, was never completely eliminated, primarily because the effect of plenum pressure changes on the velocities along the contour could not be accurately predicted

BAMBI: BLUETOOTH ACCESS MANAGEMENT & BEACON IDENTIFICATION

Cybersecurity is a constantly developing field. Patches that secured yesterday’s technology do not safeguard against occurring threats, necessitating continuous research in the field. The outbreak of Bluetooth Low Energy (BLE) devices dramatically expands the attack surface. BLE is one of the most widely applicable low-power connectivity standards. The low cost, low power consumption, and ready availability of BLE modules have made them a popular wireless technology for Internet of Things (IoT) devices and power constrained applications. However, the deployment of BLE-enabled devices enlarges the network attack surface. In spite of that, access management is insufficient for Bluetooth Low Energy devices. To elucidate, understanding the difference between known and unknown, malicious and non-malicious devices within a perimeter can be crucial in today’s cyberspace. This research proposes an approach called BAMBI - Beacon Access Management and Beacon Identification, which sought to develop an efficient, accurate, and easy-to implement solution for device/beacon identification and access management. The proposed solution, BAMBI, addresses these areas for the Bluetooth Low Energy Protocol. There are a few components to BAMBI that make up this solution. Device Identification, Device Classification, and Access Management are components that make BAMBI the first of its kind for the BLE protocol. Although this research is limited to the BLE protocol, it does introduce avenues for other connectivity standards such as Zig-bee and Bluetooth to adapt without much overhead

Navegação autónoma para robôs de serviço em ambientes interiores usando faróis

Nowadays robots are becoming more present in our daily life performing a variety of on-demand services. In order to perform autonomous tasks the robot should be aware of its environment. To achieve this goal, there are three main problems to solve: mapping, localisation and navigation. During this work, we developed an autonomous welcome robot for the Institute of Electronics and Informatics Engineering of Aveiro ( IEETA ) with the capacity to receive requests from a visitor and guide him to the requested destination. At the end of this task, the robot should return autonomously to its docking station. To accomplish this goal we studied algorithms related to the three referred problems. As an example, a laser-based solution is used for the Simultaneous Localisation and Mapping procedure ( Gmapping ), the adaptive Monte Carlo localisation approach (AMCL) for the robot moving in 2-D and A* as a method for path planning. Improvements have been made regarding the use of these algorithms including in the environment an active localisation system based on the use of ultrasound beacons. The end result is an autonomous agent capable of mapping the building, self-localise in the resulting map and moving from current position to a specified target. It is also capable of path recalculation and minimal real-time collision avoidance while navigating.Hoje em dia, os robôs estão cada vez mais presentes no nosso quotidiano, fornecendo uma variedade de serviços e realizando as mais diversas tarefas, algumas delas de forma completamente autónoma. Para que o robô execute tarefas autónomas deve estar ciente do ambiente que o rodeia e conhecer a sua posição no mesmo. Para atingir esse objetivo, existem três problemas principais a serem resolvidos: mapeamento, localização e navegação. Durante este trabalho desenvolvemos um robô autónomo de boas-vindas para o Instituto de Engenharia Eletrónica e Informática de Aveiro com a capacidade de receber ordens de um visitante e guiá-lo até ao destino solicitado. No final desta tarefa, o robô retorna autonomamente ao seu local de partida, onde retoma a tarefa de carregamento. Para atingir este objetivo estudámos algoritmos relacionados com os três problemas referidos. Como exemplo, o algoritmo GMapping baseado em laser scans é usado para o processo de Mapeamento e Localização Simultânea, a abordagem adaptativa de localização de Monte Carlo é usada para que o robô que se mova no espaço e o algoritmo A* é aplicado para planeamento de um caminho. Foram feitas diversas melhorias em relação ao uso desses algoritmos, incluindo no ambiente um sistema de localização ativa baseado no uso de beacons ultra-som. O resultado final é um agente autónomo capaz de mapear o edifício, localizarse no mapa resultante e mover-se da posição atual para um destino especificado. Também é capaz de recalcular o caminho e evitar colisões mínimas em tempo real durante a navegação.Mestrado em Engenharia de Computadores e Telemátic