Path planning for reconfigurable rovers in planetary exploration

This paper introduces a path planning algorithm that takes into consideration different locomotion modes in a wheeled reconfigurable rover. Such algorithm, based on Fast Marching, calculates the optimal path in terms of power consumption between two positions, providing the most appropriate locomotion mode to be used at each position. Finally, the path planning algorithm is validated on a virtual Martian scene created within the V-REP simulation platform, where a virtual model of a planetary rover prototype is controlled by the same software that is used on the real one. Results of this contribution also demonstrate how the use of two locomotion modes, wheel-walking and normal-driving, can reduce the power consumption for a particular area.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Cancioneros y codicología. Propuesta de un modelo de descripción codicológica

[Resumo] O estudo codicolóxico e paleográfico é o paso primeiro e fundamental para coñecer calquera manuscrito ou impreso. Neste artigo, sen pretensións de ser unha lección nova para expertos e avezados codicólogos e paleógrafos, elabórase o esquema dunha das posibles formas de se achegar ao estudo codicolóxico. Trátase dun esquema integrador doutros modelos e que aquí se ten aplicado exclusivamente a cancioneiros manuscritos do século XV, que teñen servido para exemplificar algún dos problemas concretos que presentan tanto a descrición interna como externa dos mesmos.[Resumen] El estudio codicológico y paleográfico es el paso primero y fundamental para conocer cualquier manuscrito o impreso. En este artículo, sin pretensiones de ser una lección nueva para expertos y avezados codicólogos y paleógrafos, se elabora el esquema de una de las posibles formas de acercarse al estudio codicológico. Se trata de un esquema integrador de otros modelos y que aquí se ha aplicado exclusivamente a cancioneros manuscritos del siglo XV, los cuales han servido para ejemplificar algunos problemas concretos que plantean tanto la descripción interna como externa de los mismos.[Abstract] The first step to approach to the study of any manuscript or print is the codicological and palaeographic study. The aim of this article is to offer a codicological scheme, which is not a new one, but one of the possible ways of approaching to the manuscript. The model has been applied in here exclusively to manuscript songbooks of the 15th century, which have served to exemplify some concrete problems that rise from the internal and external descriptions. KEYWORDS: songbooks, codicology, manuscripts, cancionero poetry

Multi-scale path planning for a planetary exploration vehicle with multiple locomotion modes

Planetary exploration vehicles (rovers) can encounter with a great variety of situations. Most of them are related to the terrain, which can cause the end of the mission if these vehicles are not able to traverse it. It was the case of Spirit rover, which got stuck in loose sand, making it impossible to continue advancing. A solution to this is to make rovers capable of modifying their locomotion to traverse terrains with particular terramechanic parameters.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

One dimensional particle mover and PIC code applied to electron cyclotron resonance thruster

This project aims to describe a simplified model of the plasma-wave interaction that occurs inside the chamber of a typical Electron Cyclotron Resonance Thruster. As its name suggests, ECR thrusters are based on the resonance of the electron with a given polarized electromagnetic wave, the so-called, Right Hand Polarized wave. This is a problem known since the early 60’s, however, due to technical reasons, the reseaech was abandoned. Recently, it has been resumed by research institutes as Onera or universities as UC3M, in the context of MINOTOR H2020 project. The project is devoted in the construction of a code that allows to study the interaction of a given population of electrons with a prescribed RHP wave, which it is assumed to be constant despite the changes on plasma properties. Different parameters will be studied and followed along time to check how the resonance affects the initial electron parameters. The second second part of this project is the introduction of numerical computation in plasma physics with the add-on of a PIC code, where particle properties are weighted inside a grid mesh.Ingeniería Aeroespacial (Plan 2010

Markov chains and Markov chain Monte Carlo methods

Treballs Finals de Grau de Matemàtiques, Facultat de Matemàtiques, Universitat de Barcelona, Any: 2022, Director: Carles Rovira Escofet[en] The aim of this project is to thoroughly study the main properties of discretetime Markov chains with finite state spaces and one of its applications that finds greatest usage, Markov chain Monte Carlo (MCMC) methods, which are simulation tools to estimate integrals and sample from distributions. A brief description of regular Monte Carlo is included to introduce and understand MCMC. Aside from the theoretical description and algorithms, practical considerations to take into account when implementing MCMC, such as the thermalization of chains and determining the number of iterations, are included as well. A simple example of the calculation of $\Gamma(3 / 2)$ is executed so as to illustrate the functioning and performance of MCMC

Smart Navigation in Surgical Robotics

La cirugía mínimamente invasiva, y concretamente la cirugía laparoscópica, ha supuesto un gran cambio en la forma de realizar intervenciones quirúrgicas en el abdomen. Actualmente, la cirugía laparoscópica ha evolucionado hacia otras técnicas aún menos invasivas, como es la cirugía de un solo puerto, en inglés Single Port Access Surgery. Esta técnica consiste en realizar una única incisión, por la que son introducidos los instrumentos y la cámara laparoscópica a través de un único trocar multipuerto. La principal ventaja de esta técnica es una reducción de la estancia hospitalaria por parte del paciente, y los resultados estéticos, ya que el trocar se suele introducir por el ombligo, quedando la cicatriz oculta en él. Sin embargo, el hecho de que los instrumentos estén introducidos a través del mismo trocar hace la intervención más complicada para el cirujano, que necesita unas habilidades específicas para este tipo de intervenciones. Esta tesis trata el problema de la navegación de instrumentos quirúrgicos mediante plataformas robóticas teleoperadas en cirugía de un solo puerto. En concreto, se propone un método de navegación que dispone de un centro de rotación remoto virtual, el cuál coincide con el punto de inserción de los instrumentos (punto de fulcro). Para estimar este punto se han empleado las fuerzas ejercidas por el abdomen en los instrumentos quirúrgicos, las cuales han sido medidas por sensores de esfuerzos colocados en la base de los instrumentos. Debido a que estos instrumentos también interaccionan con tejido blando dentro del abdomen, lo cual distorsionaría la estimación del punto de inserción, es necesario un método que permita detectar esta circunstancia. Para solucionar esto, se ha empleado un detector de interacción con tejido basado en modelos ocultos de Markov el cuál se ha entrenado para detectar cuatro gestos genéricos. Por otro lado, en esta tesis se plantea el uso de guiado háptico para mejorar la experiencia del cirujano cuando utiliza plataformas robóticas teleoperadas. En concreto, se propone la técnica de aprendizaje por demostración (Learning from Demonstration) para generar fuerzas que puedan guiar al cirujano durante la resolución de tareas específicas. El método de navegación propuesto se ha implantado en la plataforma quirúrgica CISOBOT, desarrollada por la Universidad de Málaga. Los resultados experimentales obtenidos validan tanto el método de navegación propuesto, como el detector de interacción con tejido blando. Por otro lado, se ha realizado un estudio preliminar del sistema de guiado háptico. En concreto, se ha empleado una tarea genérica, la inserción de una clavija, para realizar los experimentos necesarios que permitan demostrar que el método propuesto es válido para resolver esta tarea y otras similares

Path Planning for Reconfigurable Rovers in Planetary Exploration

This paper introduces a path planning algorithm that takes into consideration different locomotion modes in a wheeled reconfigurable rover. Power consumption and traction are estimated by means of simplified dynamics models for each locomotion mode. In particular, wheel-walking and normaldriving are modeled for a planetary rover prototype. These models are then used to define the cost function of a path planning algorithm based on fast marching. It calculates the optimal path, in terms of power consumption, between two positions, providing the most appropriate locomotion mode to be used at each position. Finally, the path planning algorithm was implemented in V-REP simulation software and a Martian area was used to validate it. Results of this contribution also demonstrate how the use of these locomotion modes would reduce the power consumption for a particular area.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Color and optical properties of 3D printing restorative polymer-based materials: A scoping review

Objective: Color and optical properties are particularly crucial to mimic natural tooth. This scoping review aimed to present an overview of the literature published on color and optical properties of 3D printing restorative polymer-based materials. The litera- ture search was performed in MED-LINE/Pubmed, Scopus and Web of Science. Materials and methods: The literature search was conducted in the three databases based on the question: “Are the optical properties and color adequately reported on polymer-based 3D printing dental restorative materials studies?” with no restriction on year of publication. Data were reported and synthesized following PRISMA-ScR statement. Results: Nine studies fit the inclusion criteria. Five studies focused on evaluating only color stability; three articles assessed the color stability along with mechanical and morphological properties and only one study compared color parameters of 3D printed to conventional polymers. Two studies evaluated translucency parameter and no study was found evaluating scattering, absorption, and transmittance. Conclusions: Color and optical properties of 3D printed polymers that can be used in restorative dentistry are not adequately evaluated and characterized. Future studies on the influence of experimental printing conditions should include these physical properties to assist on improving esthetics. Clinical significance: This review shows the scarce literature existing on color and optical properties of 3D printing restorative polymer-based materials. These proper- ties and their study are of outmost importance to create materials that mimic natural tooth to allow clinicians to obtain esthetically pleasant restorations.i + D + I Government of Andalusia 2020, Spain (P20-00200)University of Granada, Spain (A.TEP.280. UGR18)Spanish Ministry of Science, Innovation and Universities (PGC2018-101904-A-100)State of Rio Grande do Sul, FAPERGS (grant#19/2551-0001721-9)

GlSch: Observation Scheduler for the GLORIA Telescope Network

This paper proposes the design and development of a scheduler for the GLORIA telescope network. This network, which main objective is to make astronomy closer to citizens in general, is formed by 18 telescopes spread over four continents and both hemispheres. Part of the management of this network is made by the network scheduler. It receives the observation requests made by the GLORIA users and then sends it to the most suitable telescope. A key module of the network scheduler is the telescope decision algorithm that makes possible to choose the best telescope, and thus avoiding offering an observation to a telescope that cannot execute it. This paper shows two different telescope decision algorithms: the first one is only based on weather forecast, meanwhile the second one uses fuzzy logic and information from each network telescope. Both algorithms were deployed in the GLORIA network. The achieved results coupled with a comparative of their performance is shown. Moreover, the network scheduler architecture, based on a hybrid distributed-centralized schema, is detailed.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech