Cognitive test-bed for wireless sensor networks

Cognitive Wireless Sensor Networks are an emerging technology with a vast potential to avoid traditional wireless problems such as reliability, interferences and spectrum scarcity in Wireless Sensor Networks. Cognitive Wireless Sensor Networks test-beds are an important tool for future developments, protocol strategy testing and algorithm optimization in real scenarios. A new cognitive test-bed for Cognitive Wireless Sensor Networks is presented in this paper. This work in progress includes both the design of a cognitive simulator for networks with a high number of nodes and the implementation of a new platform with three wireless interfaces and a cognitive software for extracting real data. Finally, as a future work, a remote programmable system and the planning for the physical deployment of the nodes at the university building is presented.

Toward Visual Autonomous Ship Board Landing of a VTOL UAV

In this paper we tackle the problem of landing a helicopter autonomously on a ship deck, using as the main sensor, an on-board colour camera. To create a test-bed, we first adequately simulate the movement of a ship landing platform on the Sea, for different Sea States, for different ships, randomly and realistically enough. We use a commercial parallel robot to get this movement. Once we had this, we developed an accurate and robust computer vision system to measure the pose of the helipad with respect to the on-board camera. To deal with the noise and the possible fails of the computer vision, a state estimator was created. With all of this, we are now able to develop and test a controller that closes the loop and finish the autonomous landing task.

Control por modos deslizantes como estrategia de navegación en una flota de robots

En esta tesis se presenta el desarrollo de un esquema de cooperación entre vehículos terrestres (UGV) y aéreos (UAV) no tripulados, que sirve de base para conformar dos flotas de robots autónomos (denominadas FRACTAL y RoMA). Con el fin de comprobar, en diferentes escenarios y con diferente tareas, la validez de las estrategias de coordinación y cooperación propuestas en la tesis se utilizan los robots de la flota FRACTAL, que sirven como plataforma de prueba para tareas como el uso de vehículos aéreos y terrestres para apoyar labores de búsqueda y rescate en zonas de emergencia y la cooperación de una flota de robots para labores agrícolas. Se demuestra además, que el uso de la técnica de control no lineal conocida como Control por Modos Deslizantes puede ser aplicada no solo para conseguir la navegación autónoma individual de un robot aéreo o terrestre, sino también en tareas que requieren la navegación coordinada y sin colisiones de varios robots en un ambiente compartido. Para esto, se conceptualiza teóricamente el uso de la técnica de Control por Modos Deslizantes como estrategia de coordinación entre robots, extendiendo su aplicación a robots no-holonómicos en R2 y a robots aéreos en el espacio tridimensional. Después de dicha contextualización teórica, se analizan las condiciones necesarias para determinar la estabilidad del sistema multi-robot controlado y, finalmente, se comprueban las características de estabilidad y robustez ofrecidas por esta técnica de control. Tales comprobaciones se hacen simulando la navegación segura y eficiente de un grupo de UGVs para la detección de posibles riesgos ambientales, aprovechando la información aportada por un UAV. Para estas simulaciones se utilizan los modelos matemáticos de robots de la flota RoMA. Estas tareas coordinadas entre los robots se hacen posibles gracias a la efectividad, estabilidad y robustez de las estrategias de control que se desarrollan como núcleo fundamental de este trabajo de investigación. ABSTRACT This thesis presents the development of a cooperation scheme between unmanned ground (UGV) and aerial (UAV) vehicles. This scheme is the basis for forming two fleets of autonomous robots (called FRACTAL and RoMA). In order to assess, in different settings and on different tasks, the validity of the coordination and cooperation strategies proposed in the thesis, the FRACTAL fleet robots serves as a test bed for tasks like using coordinated aerial and ground vehicles to support search and rescue work in emergency scenarios or cooperation of a fleet of robots for agriculture. It is also shown that using the technique of nonlinear control known as Sliding Modes Control (SMC) can be applied not only for individual autonomous navigation of an aircraft or land robot, but also in tasks requiring the coordinated navigation of several robots, without collisions, in a shared environment. To this purpose, a strategy of coordination between robots using Sliding Mode Control technique is theoretically conceptualized, extending its application to non-holonomic robots in R2 and aerial robots in three-dimensional space. After this theoretical contextualization, the stability conditions of multi-robot system are analyzed, and finally, the stability and robustness characteristics are validated. Such validations are made with simulated experiments about the safe and efficient navigation of a group of UGV for the detection of possible environmental hazards, taking advantage of the information provided by a UAV. This simulations are made using mathematical models of RoMA fleet robots. These coordinated tasks of robots fleet are made possible thanks to the effectiveness, stability and robustness of the control strategies developed as core of this research.

Network convergence and QoS for future multimedia services in the VISION project

The emerging use of real-time 3D-based multimedia applications imposes strict quality of service (QoS) requirements on both access and core networks. These requirements and their impact to provide end-to-end 3D videoconferencing services have been studied within the Spanish-funded VISION project, where different scenarios were implemented showing an agile stereoscopic video call that might be offered to the general public in the near future. In view of the requirements, we designed an integrated access and core converged network architecture which provides the requested QoS to end-to-end IP sessions. Novel functional blocks are proposed to control core optical networks, the functionality of the standard ones is redefined, and the signaling improved to better meet the requirements of future multimedia services. An experimental test-bed to assess the feasibility of the solution was also deployed. In such test-bed, set-up and release of end-to-end sessions meeting specific QoS requirements are shown and the impact of QoS degradation in terms of the user perceived quality degradation is quantified. In addition, scalability results show that the proposed signaling architecture is able to cope with large number of requests introducing almost negligible delay.

Improving Speech Interaction in Vehicles Using Context-Aware Information through A SCXML Framework

Speech Technologies can provide important benefits for the development of more usable and safe in-vehicle human-machine interactive systems (HMIs). However mainly due robustness issues, the use of spoken interaction can entail important distractions to the driver. In this challenging scenario, while speech technologies are evolving, further research is necessary to explore how they can be complemented with both other modalities (multimodality) and information from the increasing number of available sensors (context-awareness). The perceived quality of speech technologies can significantly be increased by implementing such policies, which simply try to make the best use of all the available resources; and the in vehicle scenario is an excellent test-bed for this kind of initiatives. In this contribution we propose an event-based HMI design framework which combines context modelling and multimodal interaction using a W3C XML language known as SCXML. SCXML provides a general process control mechanism that is being considered by W3C to improve both voice interaction (VoiceXML) and multimodal interaction (MMI). In our approach we try to anticipate and extend these initiatives presenting a flexible SCXML-based approach for the design of a wide range of multimodal context-aware HMI in-vehicle interfaces. The proposed framework for HMI design and specification has been implemented in an automotive OSGi service platform, and it is being used and tested in the Spanish research project MARTA for the development of several in-vehicle interactive applications.

Wake-up architecture for Wireless sensor nodes based on ultra low power FPGA

In this work a novel wake-up architecture for wireless sensor nodes based on ultra low power FPGA is presented. A simple wake up messaging mechanism for data gathering applications is proposed. The main goal of this work is to evaluate the utilization of low power configurable devices to take advantage of their speed, flexibility and low power consumption compared with traditional approaches, based on ASICs or microcontrollers, for frame decoding and data control. A test bed based on infrared communications has been built to validate the messaging mechanism and the processing architecture.

Low-speed longitudinal controllers for mass-produced cars: A comparative study

Four longitudinal control techniques are compared: a classical Proportional-Integral (PI) control; an advanced technique-called the i-PI-that adds an intelligent component to the PI; a fuzzy controller based on human experience; and an adaptive-network-based fuzzy inference system. The controllers were designed to tackle one of the challenging topics as yet unsolved by the automotive sector: managing autonomously a gasoline-propelled vehicle at very low speeds. The dynamics involved are highly nonlinear and constitute an excellent test-bed for newly designed controllers. A Citroën C3 Pluriel car was modified to permit autonomous action on the accelerator and the brake pedals-i.e., longitudinal control. The controllers were tested in two stages. First, the vehicle was modeled to check the controllers' feasibility. Second, the controllers were then implemented in the Citroën, and their behavior under the same conditions on an identical real circuit was compared.

Wireless measurement system for structural health monitoring with high time synchronization accuracy

Structural health monitoring (SHM) systems have excellent potential to improve the regular operation and maintenance of structures. Wireless networks (WNs) have been used to avoid the high cost of traditional generic wired systems. The most important limitation of SHM wireless systems is time-synchronization accuracy, scalability, and reliability. A complete wireless system for structural identification under environmental load is designed, implemented, deployed, and tested on three different real bridges. Our contribution ranges from the hardware to the graphical front end. System goal is to avoid the main limitations of WNs for SHM particularly in regard to reliability, scalability, and synchronization. We reduce spatial jitter to 125 ns, far below the 120 μs required for high-precision acquisition systems and much better than the 10-μs current solutions, without adding complexity. The system is scalable to a large number of nodes to allow for dense sensor coverage of real-world structures, only limited by a compromise between measurement length and mandatory time to obtain the final result. The system addresses a myriad of problems encountered in a real deployment under difficult conditions, rather than a simulation or laboratory test bed.

Assessment of troughput performance under NS2 in Mobile Ad Hoc Networks (MANETs)

Providing QoS in the context of Ad Hoc networks includes a very wide field of application from the perspective of every level of the architecture in the network.In order for simulation studies to be useful, it is very important that the simulation results match as closely as possible with the test bed results. In this Paper, we study the throughput performance (parameter QoS) in Mobile Ad Hoc Networks (MANETs) and compares emulated test bed results with simulation results from NS2 (Network Simulator). The performance of the Mobile Ad Hoc Networks is very sensitive to the number of users and the offered load. When the number of users/offered load is high then the collisions increase resulting in larger wastage of the medium and lowering overall throughput. The aim of this research is to compare the throughput of Mobile Ad Hoc Networks using three different scenarios: 97, 100 and 120 users (nodes) using simulator NS2. By analyzing the graphs in MANETs, it is concluded When the number of users o nodes is increased beyond the certain limit, throughput decreases.

Broadband access in complex environments: LTE on railway

This paper assesses the main challenges associated with the propagation and channel modeling of broadband radio systems in a complex environment of high speed and metropolitan railways. These challenges comprise practical simulation, modeling interferences, radio planning, test trials and performance evaluation in different railway scenarios using Long Term Evolution (LTE) as test case. This approach requires several steps; the first is the use of a radio propagation simulator based on ray-tracing techniques to accurately predict propagation. Besides the radio propagation simulator, a complete test bed has been constructed to assess LTE performance, channel propagation conditions and interference with other systems in real-world environments by means of standard-compliant LTE transmissions. Such measurement results allowed us to evaluate the propagation and performance of broadband signals and to test the suitability of LTE radio technology for complex railway scenarios.

Evolving a core Banking enterprise architecture: leveraging business events exploitation

Business information has become a critical asset for companies and it has even more value when obtained and exploited in real time. This paper analyses how to integrate this information into an existing banking Enterprise Architecture, following an event-driven approach, and entails the study of three main issues: the definition of business events, the specification of a reference architecture, which identifies the specific integration points, and the description of a governance approach to manage the new elements. All the proposed solutions have been validated with a proof-of-concept test bed in an open source environment. It is based on a case study of the banking sector that allows an operational validation to be carried out, as well as ensuring compliance with non-functional requirements. We have focused these requirements on performance.

Escaparates de la modernidad : la tienda como laboratorio de arquitectura

El proyecto de una tienda concentra un poco de todo aquello que interesa al arquitecto: conforma una suerte de encrucijada en la que se dan cita, junto a cuestiones disciplinares que la hacen muy atractiva y ponen a prueba su habilidad como proyectista, la necesidad de aunar recursos compositivos procedentes de otros terrenos periféricos a la arquitectura para dar una respuesta adecuada a los requerimientos específicos de imagen y persuasión que la actividad comercial comporta. Las difíciles condiciones de partida, habitualmente configuraciones espaciales no excesivamente favorables, donde las preexistencias y los contornos coartan y encierran un espacio al que hay que dotar de un nuevo orden; el tamaño reducido y las posibilidades de control total de la obra que de éste se derivan; el corto plazo de tiempo y la rapidez de respuesta que la estrategia comercial impone; su posición estratégica, en relación directa con la calle, y la mayor evidencia que, por tanto, se le asigna a la fachada y al escaparate como ‘primeros anuncios’ de la actividad; la integración y el comentario recíproco entre arquitectura y objeto que tiene lugar en su seno…, son algunas de las razones que explican este interés y justifican que la tienda −ese espacio acotado tan apto para el invento y la innovación−, constituya un banco de pruebas donde poder ensayar nuevos conceptos de la arquitectura al reunir espacial y temporalmente los condicionantes ideales requeridos para la experimentación y la comprobación de hallazgos. Aunque escasas, existen en la arquitectura contemporánea tiendas que han logrado ocupar por méritos propios un lugar destacado dentro de la obra de sus autores. Entre las merecedoras de ese reconocimiento habría que citar la ‘mítica’ sastrería Kniže proyectada por Adolf Loos a comienzos del siglo XX en Viena, el Negozio Vitrum que Giuseppe Terragni diseñara en Como en los años treinta, o la sucursal londinense de las líneas aéreas de Iraq construida en los sesenta por Alison y Peter Smithson. La elección, lejos de ser gratuita, obedece a razones fundadas. Dentro de las circunstancias temporales en las que se gestaron −las tres fueron proyectadas y construidas a lo largo del pasado siglo en un arco que abarca algo más de cincuenta años (1907-1961)−, los ejemplos seleccionados aúnan toda una serie de ‘coincidencias’ entre las que no resulta difícil establecer ciertos paralelismos: las tres marcan la talla de unos creadores que fueron capaces de dedicar la misma intensidad creativa a estos temas ‘menores’, corroborando que el carácter de la arquitectura también puede hacerse grande en lo pequeño; las tres, debido al momento de madurez en el que se abordó su diseño, reflejan su condición de laboratorio experimental al servicio de los intereses proyectuales que en ese momento ocupaban la mente de los arquitectos; las tres corroboran hipótesis ya apuntadas en arquitecturas anteriores, prueban líneas de trabajo no materializadas por falta de oportunidad y testan de manera menos comprometida soluciones que luego se trasladarán a obras con mayor vocación de permanencia; obras −y esto es algo especialmente sorprendente− con las que mantuvieron una estrecha relación en el espacio y en el tiempo, convirtiéndose incluso en plataformas de experimentación paralelas: baste en este sentido con apuntar la cercanía física −a ‘metros’ de distancia− y temporal −realizadas en los mismos años− entre la sastrería Kniže (1907- 1913;1928) y la Casa en la Michaelerplatz (1910-11); la tienda Vitrum (1930) y la Casa del Fascio (1929; 1932-36) o las oficinas de venta de las Iraqi Airways (1960-61) y la sede del The Economist (1959-64). Esta potencialidad que la tienda encierra para erigirse en laboratorio de experimentación y ensayo de la arquitectura, constituye la clave de la investigación que la tesis propone. ABSTRACT A little of everything that interests the architect is concentrated in the designing of a shop: it forms a kind of crossroads bringing together, apart from certain disciplinary questions rendering it particularly attractive and testing one’s ability as a designer, the need to coordinate compositional resources from fields peripheral to architecture in order to devise an adequate response to the specific requirements of image and persuasion that are part and parcel of business activity. The difficult start-up conditions, the generally not overly favourable spatial configurations ‒where the pre-existing conditions and shape of the site encroach on and enclose a space which has to be given a new order‒, the reduced size and possibilities afforded in terms of controlling the work, the short time frame and the rapid response imposed by the business tactics and its strategic position and direct frontal relationship with the street, make the shopfront and the display window are the ‘first advertisements” of the activity, or the integration and the reciprocal commentary between architecture and what takes place within: these are but some of the reasons explaining this interest and justifying the claim that the shop –a dimensional space so well suited to invention and innovation− constitutes a test-bed for trying out new concepts of architecture, combining in space and time the ideal conditions for experiment and the examination of its findings. Albeit not numerous, there are shops in contemporary architecture which have managed on their own merit to obtain a special place among the works of their authors. Among those earning such recognition, one should mention the ‘mythical’ Kniže tailoring establishment designed by Adolf Loos at the beginning of the 20th century in Vienna, the Negozio Vitrum designed by Giuseppe Terragni in Como in the thirties, or the London offices of Iraqi Airways built in the sixties by Alison and Peter Smithson. This selection, far from gratuitous, is based on well-founded reasons. Within the circumstances of the time-frame in which they were developed −the three were designed and built during the 20th century in a period that spans just over fifty years (1907-1961)− the chosen examples bring together a whole series of ‘coincidences’ where it is not difficult to draw certain parallels: the three bear witness to the stature of creators who were capable of devoting the same creative intensity to these ‘minor’ themes, thus corroborating the fact that the nature of the architecture can also be great in less important works; the three, thanks to the moment of maturity in which their design was carried out, reflect their condition as an experimental laboratory at the service of the particular designing interests which at the time occupied the minds of these architects; the three confirm hypotheses already displayed in previous architectures, they test lines of work which had not materialised through lack of opportunity, and in a less comprised manner check solutions that were later transferred to works with a greater vocation for permanence; works −and this is something especially surprising – with which they maintained a close relationship in time and space, even becoming parallel experimental platforms: in this sense, we need only to mention the physical proximity –just metres away− and proximity in time –built within the same years− between the Kniže shop (1907-1913; 1928) and the House of Michaelerplatz (1910-11); the Vitrum shop (1930) and the Casa del Fascio (1929;1932-36); and the Iraqi Airways sales offices (1960-61) and the headquarters of The Economist (1959-64). The potential of the shop to set itself up as an experimental laboratory and architectural rehearsal constitutes the main focus of the research put forward by this thesis.

Acute effects of endurance exercise on jumping and kicking performance in top-class young soccer players

The aim of this study was to examine the acute effects of endurance exercise on jumping and kicking performance in young soccer players. Twenty-one top-class young soccer players (16.1±0.2 years) performed a countermovement jump test and a maximal instep soccer kick test before and after running for 20 min on a treadmill at 80% of their individual maximum heart rate. Two force platforms were used to obtain the following parameters during the countermovement jump: jump height, maximum power, maximum power relative to body mass, maximum vertical ground reaction force, maximum vertical ground reaction force relative to body mass, and maximum vertical ground reaction force applied to each leg. Maximum vertical ground reaction force and maximum vertical ground reaction force relative to body mass applied to the support leg during the kicks were also calculated with a force platform. The kicking motion was recorded using a three-dimensional motion-capture system. Maximum velocity of the ball, maximum linear velocity of the toe, ankle, knee and hip, and linear velocity of the toe at ball contact during the kicks were calculated. Non-significant differences were found in the parameters measured during the countermovement jump and the maximal instep soccer kick test before and after running, suggesting that the jumping and kicking performances of top-class young soccer players were not significantly affected after 20 min treadmill running at 80% of their individual maximum heart rate.

Visual Servoing for the Robotenis System: a Strategy for a 3 DOF Parallel Robot to Hit a Ping-Pong Ball

This article describes a new visual servo control and strategies that are used to carry out dynamic tasks by the Robotenis platform. This platform is basically a parallel robot that is equipped with an acquisition and processing system of visual information, its main feature is that it has a completely open architecture control, and planned in order to design, implement, test and compare control strategies and algorithms (visual and actuated joint controllers). Following sections describe a new visual control strategy specially designed to track and intercept objects in 3D space. The results are compared with a controller shown in previous woks, where the end effector of the robot keeps a constant distance from the tracked object. In this work, the controller is specially designed in order to allow changes in the tracking reference. Changes in the tracking reference can be used to grip an object that is under movement, or as in this case, hitting a hanging Ping-Pong ball. Lyapunov stability is taken into account in the controller design.

Diseño y Desarrollo de un Robot de Inspección de Tuberías

El siguiente trabajo presenta un desarrollo innovador de un Robot de Inspección de Tuberías, el cual fue diseñado para operación de Tuberías Verticales (RETOV Robot de operación en tuberías Verticales (siglas en Español)). Cuando RETOV es usado para inspeccionar pozos petroleros, puede ser controlado desde la superficie, esto permite al operador la inspección y monitoreo del pozo. Esto es efectuado a través de una interfaz de usuario que controla el Robot. RETOV fue diseñado con anillos articulados que abrazan la tubería, un nuevo sistema de amortiguación y ruedas móviles brinda la posibilidad de navegar y evitar obstáculos en la tubería realizando tres tipos de movimientos: rotación, traslación y helicoidal. Adicionalmente RETOV fue diseñado para realizar inspección entre dos tuberías(la tubería de producción y el pozo petrolero), con un sistema de seguridad y una estructura liviana, RETOV puede ser equipado con sensores para medir las variables de interés en el pozo. El diseño de la mecánica y el programa de control, la instrumentación, los modelos matemáticos y resultados de las pruebas han sido descritos en esta Tesis. The following Doctoral Thesis presents an innovative application of a Pipe Inspection Robot, which was designed especially as Operation Robot in Vertical Pipes (RETOV) (Robot for operation vertical pipes (Spanish acronyms)). When RETOV is used to inspect Oil Well, can be controlled from the surface, it´s allow the operator the well inspection and monitoring. This is done through our interface that controls the robot. The RETOV was designed with an articulated ring systems that embrace the pipe, a new damping systems and mobile wheels bring the possibility to navigate and avoid obstacles into the well, performing three types of movement: Rotational, translational and screw. Additional, RETOV was designed to perform the inspection between two pipes (pipe and oil well production), with a security braking systems and lightweight structure; RETOV can be equipment with sensors to measure the variables of interest in the well. The hardware and Software design, the instrumentation, the mathematical models, and the test results have been described in this thesis.