Mobile Robot Lab Project to Introduce Engineering Students to Fault Diagnosis in Mechatronic Systems

This document is a self-archiving copy of the accepted version of the paper. Please find the final published version in IEEEXplore: http://dx.doi.org/10.1109/TE.2014.2358551This paper proposes lab work for learning fault detection and diagnosis (FDD) in mechatronic systems. These skills are important for engineering education because FDD is a key capability of competitive processes and products. The intended outcome of the lab work is that students become aware of the importance of faulty conditions and learn to design FDD strategies for a real system. To this end, the paper proposes a lab project where students are requested to develop a discrete event dynamic system (DEDS) diagnosis to cope with two faulty conditions in an autonomous mobile robot task. A sample solution is discussed for LEGO Mindstorms NXT robots with LabVIEW. This innovative practice is relevant to higher education engineering courses related to mechatronics, robotics, or DEDS. Results are also given of the application of this strategy as part of a postgraduate course on fault-tolerant mechatronic systems.This work was supported in part by the Spanish CICYT under Project DPI2011-22443

Integration of a Canine Agent in a Wireless Sensor Network for Information Gathering in Search and Rescue Missions

Search and rescue operations in the context of emergency response to human or natural disasters have the major goal of finding potential victims in the shortest possible time. Multi-agent teams, which can include specialized human respondents, robots and canine units, complement the strengths and weaknesses of each agent, like all-terrain mobility or capability to locate human beings. However, efficient coordination of heterogeneous agents requires specific means to locate the agents, and to provide them with the information they require to complete their mission. The major contribution of this work is an application of Wireless Sensor Networks (WSN) to gather information from a multi-agent team and to make it available to the rest of the agents while keeping coverage. In particular, a canine agent has been equipped with a mobile node installed on a harness, providing information about the dog’s location as well as gas levels. The configuration of the mobile node allows for flexible arrangement of the system, being able to integrate static as well as mobile nodes. The gathered information is available at an external database, so that the rest of the agents and the control center can use it in real time. The proposed scheme has been tested in realistic scenarios during search and rescue exercises

Non-linear models of disability and age applied to census data

It is usually considered that the proportion of handicapped people grows with age. Namely, the older the man/woman is, the more level of disability he/she suffers. However, empirical evidence shows that this assessment is not always true, or at least, it is not true in the Spanish population. This study tries to assess the impact of age on disability in Spain. It is divided into three different parts. The first one is focused in describing the way disability is measured in this work. We used a former index defined by the authors that distinguishes between men and women. The second one is focused in a literature review about the methods used in this paper. This section emphasizes on local regression, feed forward neural networks and BARS. Finally, in the last section estimations are undertaken. Several methods are used and, therefore, there are fairly differences in the results, not only among the methodologies, but also between genders

Why using a general model in Solvency II is not a good idea : an explanation from a Bayesian point of view

The passing of Directive 2009/138/CE (Solvency II) has opened a new era in the European insurance market. According to this new regulatory environment, the volume of own resources will be determined depending on the risks that any insurer would be holding. So, nowadays, the model to estimate the amount of economic capital is one of the most important elements. The Directive establishes that the European entities can use a general model to perform these tasks. However, this situation is far from being optimal because the calibration of the general model has been made using figures that reflects and average behaviour. This paper shows that not all the companies operating in a specific market has the same risk profile. For this reason, it is unsatisfactory to use a general model for all of them. We use the PAM clustering method and afterwards some Bayesian tools to check the results previously obtained. Analysed data (public information belonging to Spanish insurance companies about balance sheets and income statements from 1998 to 2007) comes from the DGSFP (Spanish insurance regulator)

Sistema móvil de información basado en una red de sensores inalámbricos aplicado a la movilidad urbana

La movilidad en las ciudades se ve comprometida por un tráfico cada vez más elevado y unas infraestructuras que no pueden ampliarse. Por tanto, la mejora de la movilidad y su sostenibilidad deben venir de la mano de una mejor gestión de los recursos, con la incorporación de estrategias de control del tráfico que se adapten en cada momento a sus condiciones. El principal obstáculo está en la obtención de esa información. Una posibilidad son las redes de sensores inalámbricos, que pueden aportar información sobre las condiciones en una zona de interés, con vistas a una planificación más eficiente y al despliegue de algoritmos de control más elaborados.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech. Agencia de Obra Pública de la Junta de Andalucía (proyecto GI3000/IDIZ, con apoyo financiaero de los fondos FEDER

Capabilities for a cosmopolitan citizenship in higher education The experience of the Technical University of Valencia

AbstractThe capability approach (CA) has focused on how universities can enhance cosmopolitan students’ capabilities in order to contribute to a fairer and more inclusive human development model (Nussbaum, 1997). The aim of this paper is to analyze two different initiatives developed at the Universidad Politécnica de Valencia (UPV) in Spain, which have contributed to the creation and expansion of those capabilities amongst the student community. The first one is a formal space in which, since 1997, a cosmopolitan citizenship curriculum has been implemented (Boni, 2007). The second experience refers to an informal space called Mueve created by UPV students. Based on the analysis of 12 in-depth interviews we will provide some insights into the differences, similarities and synergies amongst those two spaces

Hierarchical Lee-Carter model estimation through data cloning applied to demographically linked countries

Some groups of countries are connected not only economically, but also social and even demographically. This last fact can be exploited when trying to forecast the death rates of their populations. In this paper we propose a hierarchical specification of the Lee-Carter model and we assume that there is a common latent mortality factor for all of them. We introduce an estimation procedure for this kind of structures by means of a data cloning methodology. To our knowledge, this is the first time that this methodology is used in the actuarial field. It allows approximating the maximum likelihood estimates, which are not affected by the prior distributions assumed for the calculus. Finally, we apply the methodology to some France, Italy, Portugal and Spain data. The forecasts obtained using this methodology can be considered as very satisfactory

Model uncertainty approach in mortality projection with model assembling methodologies

Forecasting mortality rates has become a key task for all who are concerned with payments for non-active people, such as Social Security or life insurance firms managers. The non-ending process of reduction in the mortality rates is forcing to continuously improve the models used to project these variables. Traditionally, actuaries have selected just one model, supposing that this model were able to generate the observed data. Most times the results have driven to a set of questionable decisions linked to those projections. This way to act does not consider the model uncertainty when selecting a specific one. This drawback can be reduced through model assembling. This technique is based on using the results of a set of models in order to get better results. In this paper we introduce two approaches to ensemble models: a classical one, based on the Akaike information criterion (AIC), and a Bayesian model averaging method. The data are referred to a Spanish male population and they have been obtained from the Human Mortality Database. We have used four of the most widespread models to forecast mortality rates (Lee-Carter, Renshaw-Haberman, Cairns-Blake-Dowd and its generalization for including cohort effects) together with their respective Bayesian specifications. The results suggest that using assembling models techniques gets more accurate predictions than those with the individual models

Close detection robotic platform for Search And Rescue missions based on Bluetooth Low Energy

Improvements in telecommunications and digitalization directly improve the efficacy of a wide variety of processes. Recently, detection systems have received considerable attention because of the importance of tracking infected people contacts during SARS-CoV-2 pandemic. Such implementations can be useful in the task of finding potential victims in the context of emergency response, especially in situations where GPS is not available or inspection by imaging is not practical. Radio signals come into play, and specifically from devices that transmit periodically and with low power consumption. With the rise of Internet of Things over the last years, the number of wearable devices that support BLE, such as smartbands, smartwatches or smartphones, has been increasing constantly, as well as the number of users that carry them. Those devices can provide considerable assistance in locating injured or unconscious people. This work presents a system for detecting victims by means of a terrestrial search and rescue (SAR) robot. A real implementation of a close detection robotic platform based on BLE for SAR interventions is laid out. To estimate the distance between a robotic agent and potential victims within an experimental area, a Log-distance path loss model is presented. The proposed scheme has been tested in realistic scenarios during SAR exercises.This work was partially funded by the Spanish project RTI2018-093421-B-I00. It has been also performed in the framework of the Horizon 2020 project LOCUS (ICT-871249) receiving funds from the European Union. This work has been also partially funded by Junta de Andalucía and ERDF projects: Consejería de Transformación Económica, Industria, Conocimiento y Universidades, Proyecto de Excelencia PENTA, P18-FR-4647; postdoctoral grant (Ref., DOC 01154, “selección de personal investigador doctor convocado mediante Resolución de 21 de mayo de 2020”, PAIDI 2020) and the I Plan Propio de Investigación, Transferencia y Divulgación Científica of the University of Málaga. The authors want to thank the collaboration of the Chair for Safety, Emergencies and Disasters of the University of Malaga, led by Prof. Jesús Miranda, as well as Javier Serón Barba for his support during the experiments. Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Improvement of Impact Toughness and Abrasion Resistance of a 3C-25Cr-0.5Mo Alloy Using a Design of Experiment Statistical Technique: Microstructural Correlations after Heat Treatments

[Abstract] Hypoeutectic high chromium white cast irons are commonly used in the mining and cement industries, where high resistance to abrasive wear is demanded. Through the application of a Design of Experiment technique (DoE), different factors related to thermal industrial treatments are analysed with regard to resistance to abrasive wear and impact response. Abrasion tests were carried out in accordance with the ASTM G065-16 standard. The provisional results show that to increase wear resistance, high destabilisation temperatures (1050 ◦C) followed by slow cooling to room temperature (RT) and subsequent tempering at 400 ◦C are most favourable. This is because these conditions are favourable to maintaining a certain tetragonality of the martensite after tempering and also, because of the presence of a high density of mixed carbides M7C3, through a secondary precipitation during cooling. Oil quenching and a high tempering temperature (550 ◦C) with long dwell times of 6 h were found to increase impact toughness. These conditions favour a lack of retained austenite. The presence of retained austenite was found unfavourable for both wear resistance and toughness, whereas tempering at 400 ◦C has been shown to be insufficient to transform martensite on tempering, which in turn seemed to increase the hardness of the matrix constituent