RF-Based Location Using Interpolation Functions to Reduce Fingerprint Mapping

Indoor RF-based localization using fingerprint mapping requires an initial training step, which represents a time consuming process. This location methodology needs a database conformed with RSSI (Radio Signal Strength Indicator) measures from the communication transceivers taken at specific locations within the localization area. But, the real world localization environment is dynamic and it is necessary to rebuild the fingerprint database when some environmental changes are made. This paper explores the use of different interpolation functions to complete the fingerprint mapping needed to achieve the sought accuracy, thereby reducing the effort in the training step. Also, different distributions of test maps and reference points have been evaluated, showing the validity of this proposal and necessary trade-offs. Results reported show that the same or similar localization accuracy can be achieved even when only 50% of the initial fingerprint reference points are taken

Multi-Sensor Localization and Navigation for Remote Manipulation in Smoky Areas

Abstract When localizing mobile sensors and actuators in indoor  environments  laser  meters,  ultrasonic  meters  or  even image processing techniques are usually used. On  the  other  hand,  in  smoky  conditions,  due  to  a  fire  or  building collapse, once the smoke or dust density grows,  optical  methods  are  not  efficient  anymore.  In  these  scenarios  other  type  of  sensors  must  be  used,  such  as  sonar,  radar  or  radiofrequency  signals.  Indoor  localization in low‐visibility  conditions due to  smoke is  one of the EU GUARDIANS [1] project goals.   The developed method aims to position a robot in front  of doors, fire extinguishers and other points of interest  with  enough  accuracy  to  allow  a  human  operator  to  manipulate the robot’s arm in order to actuate over the  element.  In  coarse‐grain  localization,  a  fingerprinting technique  based  on  ZigBee  and  WiFi  signals  is  used,  allowing  the robot  to  navigate  inside  the  building  in  order  to  get  near  the  point  of  interest  that  requires  manipulation.  In  fine‐grained  localization  a  remotely  controlled  programmable  high  intensity  LED  panel  is  used, which acts as a reference to the system in smoky  conditions.  Then,  smoke  detection  and  visual  fine‐ grained localization are used to position the robot with  precisely in the manipulation point (e.g., doors, valves,  etc.)

A visually-guided position control method, in underwater conditions, using an inexpensive remotely operated vehicle

Peer Reviewe

A visually-guided position control method, in underwater conditions, using an inexpensive remotely operated vehicle

Ponència presentada a 9th Martech International Workshop on Marine Technology (MARTECH 2021), Vigo, 16-18 juny, 202

CompaRob: the shopping cart assistance robot

Technology has recently been developed which offers an excellent opportunity to design systems with the ability to help people in their own houses. In particular, assisting elderly people in their environments is something that can significantly improve their quality of life. However, helping elderly people outside their usual environment is also necessary, to help them to carry out daily tasks like shopping. In this paper we present a person-following shopping cart assistance robot, capable of helping elderly people to carry products in a supermarket. First of all, the paper presents a survey of related systems that perform this task, using different approaches, such as attachable modules and computer vision. After that, the paper describes in detail the proposed system and its main features. The cart uses ultrasonic sensors and radio signals to provide a simple and effective person localization and following method. Moreover, the cart can be connected to a portable device like a smartphone or tablet, thus providing ease of use to the end user. The prototype has been tested in a grocery store, while simulations have been done to analyse its scalability in larger spaces where multiple robots could coexist.This work was partly supported by Spanish Ministry under Grant DPI2014-57746-C3 (MERBOTS Project) and by Universitat Jaume I Grants P1-1B2015-68 and PID2010-12

Utilizando Arduino Due en la docencia de la entrada/salida

Resumen: La problemática de la entrada/salida y su gestión suele formar parte de las asignaturas de introducción a la arquitectura de computadores. La propia naturaleza del tema y su diversidad hace que las sesiones prácticas se lleven a cabo habitualmente, bien sobre dispositivos específicos sencillos, bien sobre simuladores, lo que las aleja de los dispositivos reales y les resta vistosidad. Sin embargo, es posible utilizar dispositivos actuales y sencillos, como las tarjetas Arduino, para presentar a los estudiantes una visión más real y atractiva de la entrada/ salida, manteniendo a su vez la sencillez de uso de los entornos y sistemas empleados, lo que consideramos prioritario en los primeros cursos de grado. En nuestro caso, puesto que actualmente fundamentamos nuestra docencia en arquitectura de computadores sobre la arquitectura ARM, hemos optado por el modelo Arduino Due, que dispone de un microcontrolador, el ATSAM3X8E, que implementa la versión Cortex- M3 de la arquitectura ARM. Para poder realizar las prácticas de entrada/salida hemos modificado ligeramente el entorno Arduino para poder incluir programas en ensamblador, y hemos diseñado una pequeña tarjeta con un led RGB y un pulsador, lo que ha permitido proponer ejercicios sencillos pero vistosos. Los propios dispositivos del microcontrolador de la Arduino DUE han bastado para abarcar otros aspectos de la entrada/salida y presentar ejemplos de mayor complejidad para incentivar a los estudiantes. La primera experiencia con este entorno ha sido satisfactoria tanto para el profesorado de las asignaturas en las que se ha utilizado como para los estudiantes, en quienes además se ha fomentado el interés en continuar trabajando con las tarjetas Arduino en sus propios proyectos.Abstract: The input/output (I/O) and its management is often part of the introductory courses to computer architecture. The very nature of this topic and its diversity makes that the practice sessions often take place either on simple specific devices, or on simulators, which hide the complexity of actual I/O devices and subtracts their appealing. However, it is possible to use today existing and simple devices such as Arduino boards to introduce students to a more realistic and attractive vision of the I/O, while maintaining the ease of use of the required environments and systems, which we consider a priority on first degree courses. In our case, since currently we base our teaching on computer architecture on the ARM architecture, we have opted for the Arduino Due model, which has a microcontroller, ATSAM3X8E, which implements the Cortex-M3 version of the ARM Architecture. To carry out the laboratory sessions on I/O we have slightly modified the Arduino IDE in order to accept assembly source code. In addition, we have designed and built a small board with an RGB led and a switch, which allowed us to propose simple but colourful exercises. The built-in I/O included in the ARM controller of the Arduino DUE board have proved enough to explore other important aspects of I/O as well as to offer more complex examples to incentivate the students on the subject. The first experience with this environment has been satisfactory for both teachers and students, who also have fostered interest in continuing to work with Arduino cards in their own projects

Underwater radio frequency image sensor using progressive image compression and region of interest

The increasing demand for underwater robotic intervention systems around the world in several application domains requires more versatile and inexpensive systems. By using a wireless communication system, supervised semi-autonomous robots have freedom of movement; however, the limited and varying bandwidth of underwater radio frequency (RF) channels is a major obstacle for the operator to get camera feedback and supervise the intervention. This paper proposes the use of progressive (embedded) image compression and region of interest (ROI) for the design of an underwater image sensor to be installed in an autonomous underwater vehicle, specially when there are constraints on the available bandwidth, allowing a more agile data exchange between the vehicle and a human operator supervising the underwater intervention. The operator can dynamically decide the size, quality, frame rate, or resolution of the received images so that the available bandwidth is utilized to its fullest potential and with the required minimum latency. The paper focuses first on the description of the system, which uses a camera, an embedded Linux system, and an RF emitter installed in an OpenROV housing cylinder. The RF receiver is connected to a computer on the user side, which controls the camera monitoring parameters, including the compression inputs, such as region of interest (ROI), size of the image, and frame rate. The paper focuses on the compression subsystem and does not attempt to improve the communications physical media for better underwater RF links. Instead, it proposes a unified system that uses well-integrated modules (compression and transmission) to provide the scientific community with a higher-level protocol for image compression and transmission in sub-sea robotic interventions

Further teleoperated experiments with an underwater mobile manipulator via acoustic modem: modem characterization

In this study, we conducted preliminary experiments to characterize an acoustic sonar [1][2] for underwater communication. We carried on image transmission experiments and attempted to reduce reflections using insulating cork. Moving the buoy along the surface revealed the central area of the tank to have the best communication with Girona. We plan to conduct further experiments with the acoustic modem in a realistic environment. In addition, we are also testing Visible Light Communication (VLC) [3] optical modems, which yielded better results than the acoustic modem. We aim to develop a multimodal system for improved communication under different environmental conditions.Peer Reviewe

Introducción a la arquitectura de computadores con QtARMSim y Arduino

Codi d’assignatura EI1004 / MT100

Wireless Internet. 8th International Conference, WICON 2014, Lisbon, Portugal, November 13-14, 2014, Revised Selected Papers

In this paper, the influence and improvement of the localization accuracy achieved using a fingerprint database with information coming from different channels and radio signal strength levels is evaluated. This study uses IEEE 802.15.4 networks with different power levels and carrier frequency channels in the 2.4 GHz band. Experimental results show that selecting part of this information with a cleverer data processing can provide similar or better localization accuracy than using the whole database