Development of an Autonomous Blimp

The purpose of this project was to design and fabricate an autonomous dirigible-based platform that could be used to enable development of navigational controllers and provide multi-mission capability through modularity. The platform was designed to carry and interface with a variety of mission specific hardware through a standard interface. A customized hardware platform was designed including a propulsion system and integrated sensor suite. Multiple ground level tests were undertaken to determine sensor performance and the capabilities of the navigational programs

SwarMAV: A Swarm of Miniature Aerial Vehicles

As the MAV (Micro or Miniature Aerial Vehicles) field matures, we expect to see that the platform's degree of autonomy, the information exchange, and the coordination with other manned and unmanned actors, will become at least as crucial as its aerodynamic design. The project described in this paper explores some aspects of a particularly exciting possible avenue of development: an autonomous swarm of MAVs which exploits its inherent reliability (through redundancy), and its ability to exchange information among the members, in order to cope with a dynamically changing environment and achieve its mission. We describe the successful realization of a prototype experimental platform weighing only 75g, and outline a strategy for the automatic design of a suitable controller

Development of an aerial robot for inspection and surveillance

Mestrado em Engenharia MecânicaOs veículos aéreos não tripulados são cada vez mais procurados para desempenhar diversas tarefas do quotidiano. Estes sistemas são, no entanto, caros e necessitam de equipas grandes para serem operados. O controlo de veículos aéreos autónomos num ambiente parcialmente conhecido é uma tarefa complexa. Os sistemas actuais são baseados em sensores e sistemas de controlo relativamente dispendiosos, e são frequentemente pesados, necessitando de uma grande quantidade de energia. O principal objectivo deste projecto é desenvolver um sistema aéreo não tripulado, fácil de operar, para inspecção e monitorização. Integrados neste sistema encontram-se a plataforma do robô aéreo, o sistema de controlo e a estação de controlo remoto. A plataforma desenvolvida é baseada em veículos mais leves que o ar. Pretende-se que esta plataforma seja capaz de navegar por espaços confinados e também em ambientes fechados. A esta plataforma foram incorporados sensores e sistemas de controlo leves e de baixo consumo de energia. Para a estação de supervisão foi desenvolvido um programa que permite o controlo do robô e supervisão dos objectivos da missão. A interface gráfica permite de uma forma intuitiva efectuar o controlo do robô. Os testes iniciais permitiram demonstrar as capacidades dos sistemas desenvolvidos para atingir os objectivos propostos. ABSTRACT: Unmanned aerial vehicles are being increasingly sought to perform every days tasks. But these systems are still costly and require a large crew of mission controllers and pilots to adequately manoeuvre the UAV. Managing and control an autonomous air vehicle in a partially known and uncontrolled environment is a complex problem. Current UAVs are based on costly sensors and control systems. These control systems are also usually heavy and demand large amounts of power. This thesis aims to develop an easy to operate unmanned aerial system for surveillance and monitoring missions. As part of this system will be developed an aerial platform, the embedded control system, the ground station with a graphical interface. The platform designed is based on a small lighter-than-air vehicle. To successfully complete the mission objectives the UAV must be capable of navigate through constrained areas and endow indoor flights. The UAV is equipped with low power consumption sensors and processors. For the ground station will be developed an application to control and monitor the UAV status. The graphical user interface application provide an easy to use interface to control and monitor the mission objectives. The initial tests allowed to validate the feasibility of the systems developed to achieve the proposed goals

An Unmanned Lighter-Than-Air Platform for Large Scale Land Monitoring

The concept and preliminary design of an unmanned lighter-than-air (LTA) platform instrumented with different remote sensing technologies is presented. The aim is to assess the feasibility of using a remotely controlled airship for the land monitoring of medium sized (up to 107 m2) urban or rural areas at relatively low altitudes (below 1000 m) and its potential convenience with respect to other standard remote and in-situ sensing systems. The proposal includes equipment for high-definition visual, thermal, and hyperspectral imaging as well as LiDAR scanning. The data collected from these different sources can be then combined to obtain geo-referenced products such as land use land cover (LULC), soil water content (SWC), land surface temperature (LSC), and leaf area index (LAI) maps, among others. The potential uses for diffuse structural health monitoring over built-up areas are discussed as well. Several mission typologies are considere

Low computational SLAM for an autonomous indoor aerial inspection vehicle

The past decade has seen an increase in the capability of small scale Unmanned Aerial Vehicle (UAV) systems, made possible through technological advancements in battery, computing and sensor miniaturisation technology. This has opened a new and rapidly growing branch of robotic research and has sparked the imagination of industry leading to new UAV based services, from the inspection of power-lines to remote police surveillance. Miniaturisation of UAVs have also made them small enough to be practically flown indoors. For example, the inspection of elevated areas in hazardous or damaged structures where the use of conventional ground-based robots are unsuitable. Sellafield Ltd, a nuclear reprocessing facility in the U.K. has many buildings that require frequent safety inspections. UAV inspections eliminate the current risk to personnel of radiation exposure and other hazards in tall structures where scaffolding or hoists are required. This project focused on the development of a UAV for the novel application of semi-autonomously navigating and inspecting these structures without the need for personnel to enter the building. Development exposed a significant gap in knowledge concerning indoor localisation, specifically Simultaneous Localisation and Mapping (SLAM) for use on-board UAVs. To lower the on-board processing requirements of SLAM, other UAV research groups have employed techniques such as off-board processing, reduced dimensionality or prior knowledge of the structure, techniques not suitable to this application given the unknown nature of the structures and the risk of radio-shadows. In this thesis a novel localisation algorithm, which enables real-time and threedimensional SLAM running solely on-board a computationally constrained UAV in heavily cluttered and unknown environments is proposed. The algorithm, based on the Iterative Closest Point (ICP) method utilising approximate nearest neighbour searches and point-cloud decimation to reduce the processing requirements has successfully been tested in environments similar to that specified by Sellafield Ltd

Closed-Loop Behavior of an Autonomous Helicopter Equipped with a Robotic Arm for Aerial Manipulation Tasks

This paper is devoted to the control of aerial robots interacting physically with objects in the environment and with other aerial robots. The paper presents a controller for the particular case of a small‐scaled autonomous helicopter equipped with a robotic arm for aerial manipulation. Two types of influences are imposed on the helicopter from a manipulator: coherent and non ‐ coherent influence. In the former case, the forces and torques imposed on the helicopter by the manipulator change with frequencies close to those of the helicopter movement. The paper shows that even small interaction forces imposed on the fuselage periodically in proper phase could yield to low frequency instabilities and oscillations, so called phase circle

Planificación de trayectorias para un robot tipo con restricciones dinámicas

In this article we propose a method to find the optimal trajectories of a robot with dynamic constrains. The system acts in a free space and in horizontal plane (2D). A dynamic model description for the airship movement on the 2D plane is presented. This model is used in order to make the kinematic model formulation. The optimal control theory is used to find the optimal trajectory for a kind of robot subject to kinematic constraints on its path curvature and its orientation. Two modified models are considerate and with they, better-adapted trajectories to the dynamic constrains are planned. Comparisons and conclusions based over simulations are presented at the end.Este documento presenta una aproximación a la planificación de caminos óptimos para un sistema con restricciones dinámicas y desplazándose dentro de un espacio libre de obstáculos. Se considera el modelo dinámico del dirigible y un análisis para el planteamiento de modelos simplificados o comúnmente conocidos como modelos de control. Se propone una planificación de la trayectoria desde el punto de vista de la teoría óptima utilizando un modelo de la dinámica de un robot móvil (que se desplaza a velocidad constante y en avance, es decir con restricciones dinámicas) como punto de partida para la primera aproximación a los caminos óptimos. Para el suavizado de las trayectorias del dirigible se proponen dos modelos con relajación en la dinámica de la variable de control y finalmente se presenta una simulación de la comparación de los diferentes resultados