Synthesis of the Complete Inverse Kinematic Model of Non-Redundant Open-Chain Robotic Systems using Groebner Basis Theory

[ES] Uno de los elementos más importantes en el sistema de control de un robot es su Modelo Cinemático Inverso (IKM, por sus siglas en inglés), el cual calcula las referencias de posición y velocidad requeridas para que dicho robot pueda seguir una trayectoria. Los métodos más comúnmente empleados para la síntesis del IKM de sistemas robotizados de cadena cinemática abierta dependen fuertemente de la geometría del robot, por lo que no son procedimientos sistemáticos que puedan ser aplicados uniformemente en todas las situaciones. Este proyecto presenta el desarrollo de un procedimiento sistemático para la síntesis del IKM completo de sistemas robotizados no redundantes de cadena cinemática abierta usando la teoría de Bases de Groebner, el cual no depende de la geometría del robot. Las entradas del procedimiento desarrollado son los parámetros de Denavit-Hartenberg del robot y el rango de movimiento de sus actuadores, mientras que la salida es el IKM sintetizado, listo para ser usado en el sistema de control del robot o en una simulación de su funcionamiento. El desempeño del procedimiento desarrollado fue demostrado sintetizando los IKMs de un manipulador PUMA y un hexápodo caminante. Los tiempos de ejecución de ambos IKMs son comparables con los requeridos por los modelos cinemáticos calculados por procedimientos tradicionales, y los errores de las referencias que ofrecen como salida son totalmente despreciables. Los IKMs sintetizados son completos, porque no sólo ofrecen las referencias de posición para todos los actuadores del robot, sino que también calculan las correspondientes referencias de velocidades y aceleraciones de dichos actuadores, por lo que el procedimiento desarrollado puede ser empleado en una amplia variedad de sistemas robotizados.[CA] Un dels elements més importants en el sistema de control d'un robot és el seu Model Cinemàtic Invers (IKM, per les seues sigles en anglés), el qual calcula les referències de posició i velocitat requerides perquè aquest robot puga seguir una trajectòria. Els mètodes més comunament emprats per a la síntesi del IKM de sistemes robotitzats de cadena cinemàtica oberta depenen fortament de la geometria del robot analitzat, per la qual cosa no són procediments sistemàtics que puguen ser aplicats uniformement en totes les situacions. Aquest projecte presenta el desenvolupament d'un procediment sistemàtic per a la síntesi del IKM complet de sistemes robotitzats no redundants de cadena cinemàtica oberta usant la teoria de Bases de Groebner, el qual no depén de la geometria del robot. Les entrades del procediment desenvolupat són els paràmetres de Denavit-Hartenberg del robot i el rang de moviment dels seus actuadors, mentre que l'eixida és el IKM sintetitzat, llest per a ser usat en el sistema de control del robot o en una simulació del seu funcionament. L'acompliment del procediment desenvolupat va ser demostrat sintetitzant els IKMs d'un manipulador PUMA i un robot caminante. Els temps d'execució de tots dos IKMs són comparables amb els requerits pels models cinemàtics calculats per procediments tradicionals, i els errors de les referències que ofereixen com a eixida són totalment menyspreables. Els IKMs sintetitzats són complets, perquè no sols ofereixen les referències de posició per a tots els actuadors del robot, sinó que també calculen les corresponents referències de velocitats i acceleracions d'aquests actuadors, per la qual cosa el procediment desenvolupat pot ser emprat en una àmplia varietat de sistemes robotitzats.[EN] One of the most important elements of a robot's control system is its Inverse Kinematic Model (IKM), which calculates the position and velocity references required by the robot's actuators to follow a trajectory. The methods that are commonly used to synthesize the IKM of open-chain robotic systems strongly depend on the geometry of the analyzed robot, so they are not systematic procedures that can be applied equally in all situations. This project presents the development of a systematic procedure to synthesize the complete IKM of non-redundant open-chain robotic systems using Groebner Basis theory, which does not depend on the robot's geometry. The inputs to the developed procedure are the robot's Denavit-Hartenberg parameters and the movement range of its actuators, while the output is the IKM, ready to be used in the robot's control system or in a simulation of its behavior. This procedure's performance was proved synthesizing the IKMs of a PUMA manipulator and a walking hexapod robot. The computation times of both IKMs are comparable to those required by the kinematic models calculated by traditional methods, while the errors of their computed references were absolutely negligible. The synthesized IKMs are complete in the sense that they not only supply the position reference for all the robot's actuators, but also the corresponding references for their velocities and accelerations, so the developed procedure can be used in a wide range of robotic systems.Guzmán Giménez, J. (2022). Synthesis of the Complete Inverse Kinematic Model of Non-Redundant Open-Chain Robotic Systems using Groebner Basis Theory [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/181632TESI

Modelos para el análisis y optimización del control de admisión en redes celulares

En la última década se ha producido una enorme popularización de las redes celulares, siendo incluso muy superior a las previsiones iniciales más optimistas. Este interés que ha despertado entre los usuarios ha provocado que sea en la actualidad el sector de las telecomunicaciones más productivo para los operadores. Aunque el número de usuarios no se prevé que aumente al mismo ritmo a como lo ha hecho hasta ahora porque el número de líneas móviles es superior al de habitantes en muchos países, existe toda una serie de nuevos desafíos para los operadores para poder ofrecer servicios atractivos y competitivos a los usuarios. Estos nuevos servicios se prevé que demanden asimismo una mayor cantidad de recursos. Para el mundo de la investigación, esto supone la necesidad de desarrollar mecanismos cada vez más eficientes y complejos que gestionen los recursos adecuadamente para garantizar unos requisitos de calidad de servicio. Tradicionalmente, para el diseño de estos mecanismos de gestión de recursos se ha partido de las propuestas realizadas para redes fijas. No obstante, las redes celulares introducen nuevos retos por la escasez del espectro radioeléctrico, la aleatoriedad de la propagación y la movilidad de los terminales. La presente tesis doctoral toma como marco de trabajo las redes celulares que implementan políticas de control de admisión. De forma más concreta, en la primera parte de la tesis doctoral se han desarrollado modelos analíticos que permiten estudiar el impacto de los accesos repetitivos que se producen en un sistema cuando el controlador de admisión decide bloquear una petición de acceso al sistema. Esta contribución se realiza en dos aspectos: en el desarrollo de técnicas de resolución de sistemas con reintentos y en la aplicación de esas técnicas a modelos de redes celulares con el fin de comprender el impacto que los reintentos tienen en ellas. La segunda parte de la tesis doctoral está enfocada al diseño de políticas óptimas de control de admisGiménez Guzmán, JM. (2008). Modelos para el análisis y optimización del control de admisión en redes celulares [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/2936Palanci

Automatic selection of the Groebner Basis' monomial order employed for the synthesis of the inverse kinematic model of non-redundant open-chain robotic systems

This is an Author's Accepted Manuscript of an article published in José Guzmán-Giménez, Ángel Valera Fernández, Vicente Mata Amela & Miguel Ángel Díaz-Rodríguez (2023) Automatic selection of the Groebner Basis¿ monomial order employed for the synthesis of the inverse kinematic model of non-redundant open-chain robotic systems, Mechanics Based Design of Structures and Machines, 51:5, 2458-2480, DOI: 10.1080/15397734.2021.1899829 [copyright Taylor & Francis], available online at: http://www.tandfonline.com/10.1080/15397734.2021.1899829[EN] The methods most commonly used to synthesize the Inverse Kinematic Model (IKM) of open-chain robotic systems strongly depend on the robot's geometry, which make them difficult to systematize. In a previous work we presented a systematic procedure that relies on Groebner Bases to synthesize the IKM of non-redundant open-chain robots. This study expands the developed procedure with a methodology for the automatic selection of the basis' monomial order. The procedure's inputs are the robot's Denavit-Hartenberg parameters and the movement range of its actuators, while the output is the synthesized IKM, ready to be used in the robot's control system or in a simulation of its behavior. This procedure can synthesize the IKM of a wide range of open-chain robotic systems, such as Cartesian robots, SCARA, non-redundant multi-legged robots, and all non-redundant manipulators that satisfy the in-line wrist condition. The procedure's performance is assessed through two study cases of open-chain robots: a walking hexapod and a PUMA manipulator. The optimal monomial order is successfully identified for all cases. Also the output errors of the synthesized IKMs are negligible when evaluated in their corresponding workspaces, while their computation times are comparable to those required by the kinematic models calculated by traditional methods.This research was partially funded by Plan Nacional de IthornDthorni, Agencia Estatal de Investigacion del Ministerio de Economia, Industria y Competitividad del Gobierno de Espana, in the project FEDER-CICYT DPI201784201-R.Guzmán-Giménez, J.; Valera Fernández, Á.; Mata Amela, V.; Díaz-Rodríguez, MÁ. (2023). Automatic selection of the Groebner Basis' monomial order employed for the synthesis of the inverse kinematic model of non-redundant open-chain robotic systems. Mechanics Based Design of Structures and Machines. 51(5):2458-2480. https://doi.org/10.1080/15397734.2021.18998292458248051

Synthesis of the Inverse Kinematic Model of Non-Redundant Open-Chain Robotic Systems Using Groebner Basis Theory

[EN] One of the most important elements of a robot's control system is its Inverse Kinematic Model (IKM), which calculates the position and velocity references required by the robot's actuators to follow a trajectory. The methods that are commonly used to synthesize the IKM of open-chain robotic systems strongly depend on the geometry of the analyzed robot. Those methods are not systematic procedures that could be applied equally in all possible cases. This project presents the development of a systematic procedure to synthesize the IKM of non-redundant open-chain robotic systems using Groebner Basis theory, which does not depend on the geometry of the robot's structure. The inputs to the developed procedure are the robot's Denavit-Hartenberg parameters, while the output is the IKM, ready to be used in the robot's control system or in a simulation of its behavior. The Groebner Basis calculation is done in a two-step process, first computing a basis with Faugere's F4 algorithm and a grevlex monomial order, and later changing the basis with the FGLM algorithm to the desired lexicographic order. This procedure's performance was proved calculating the IKM of a PUMA manipulator and a walking hexapod robot. The errors in the computed references of both IKMs were absolutely negligible in their corresponding workspaces, and their computation times were comparable to those required by the kinematic models calculated by traditional methods. The developed procedure can be applied to all Cartesian robotic systems, SCARA robots, all the non-redundant robotic manipulators that satisfy the in-line wrist condition, and any non-redundant open-chain robot whose IKM should only solve the positioning problem, such as multi-legged walking robots.This research was partially funded by Plan Nacional de I+D+i, Agencia Estatal de Investigacion del Ministerio de Economia, Industria y Competitividad del Gobierno de Espana, in the project FEDER-CICYT DPI2017-84201-R.Guzmán-Giménez, J.; Valera Fernández, Á.; Mata Amela, V.; Díaz-Rodríguez, MÁ. (2020). Synthesis of the Inverse Kinematic Model of Non-Redundant Open-Chain Robotic Systems Using Groebner Basis Theory. Applied Sciences. 10(8):1-22. https://doi.org/10.3390/app10082781S122108Atique, M. M. U., Sarker, M. R. I., & Ahad, M. A. R. (2018). Development of an 8DOF quadruped robot and implementation of Inverse Kinematics using Denavit-Hartenberg convention. Heliyon, 4(12), e01053. doi:10.1016/j.heliyon.2018.e01053Flanders, M., & Kavanagh, R. C. (2015). Build-A-Robot: Using virtual reality to visualize the Denavit-Hartenberg parameters. Computer Applications in Engineering Education, 23(6), 846-853. doi:10.1002/cae.21656Özgür, E., & Mezouar, Y. (2016). Kinematic modeling and control of a robot arm using unit dual quaternions. Robotics and Autonomous Systems, 77, 66-73. doi:10.1016/j.robot.2015.12.005Wang, X., Han, D., Yu, C., & Zheng, Z. (2012). The geometric structure of unit dual quaternion with application in kinematic control. Journal of Mathematical Analysis and Applications, 389(2), 1352-1364. doi:10.1016/j.jmaa.2012.01.016Barrientos, A., Álvarez, M., Hernández, J. D., del Cerro, J., & Rossi, C. (2012). Modelado de Caden as Cinemáticas mediante Matrices de Desplazamiento. Una alternativa al método de Denavit-Hartenberg. Revista Iberoamericana de Automática e Informática Industrial RIAI, 9(4), 371-382. doi:10.1016/j.riai.2012.09.004Virgil Petrescu, R. V., Aversa, R., Apicella, A., Mirsayar, M., Kozaitis, S., Abu-Lebdeh, T., & Tiberiu Petrescu, F. I. (2017). Geometry and Inverse Kinematic at the MP3R Mobile Systems. Journal of Mechatronics and Robotics, 1(2), 58-65. doi:10.3844/jmrsp.2017.58.65Chen, S., Luo, M., Abdelaziz, O., & Jiang, G. (2017). A general analytical algorithm for collaborative robot (cobot) with 6 degree of freedom (DOF). 2017 International Conference on Applied System Innovation (ICASI). doi:10.1109/icasi.2017.7988522Bouzgou, K., & Ahmed-Foitih, Z. (2014). Geometric modeling and singularity of 6 DOF Fanuc 200IC robot. Fourth edition of the International Conference on the Innovative Computing Technology (INTECH 2014). doi:10.1109/intech.2014.6927745Mahajan, A., Singh, H. P., & Sukavanam, N. (2017). An unsupervised learning based neural network approach for a robotic manipulator. International Journal of Information Technology, 9(1), 1-6. doi:10.1007/s41870-017-0002-2Duka, A.-V. (2014). Neural Network based Inverse Kinematics Solution for Trajectory Tracking of a Robotic Arm. Procedia Technology, 12, 20-27. doi:10.1016/j.protcy.2013.12.451Toshani, H., & Farrokhi, M. (2014). Real-time inverse kinematics of redundant manipulators using neural networks and quadratic programming: A Lyapunov-based approach. Robotics and Autonomous Systems, 62(6), 766-781. doi:10.1016/j.robot.2014.02.005Rokbani, N., & Alimi, A. M. (2013). Inverse Kinematics Using Particle Swarm Optimization, A Statistical Analysis. Procedia Engineering, 64, 1602-1611. doi:10.1016/j.proeng.2013.09.242Jiang, G., Luo, M., Bai, K., & Chen, S. (2017). A Precise Positioning Method for a Puncture Robot Based on a PSO-Optimized BP Neural Network Algorithm. Applied Sciences, 7(10), 969. doi:10.3390/app7100969Köker, R. (2013). A genetic algorithm approach to a neural-network-based inverse kinematics solution of robotic manipulators based on error minimization. Information Sciences, 222, 528-543. doi:10.1016/j.ins.2012.07.051Rokbani, N., Casals, A., & Alimi, A. M. (2014). IK-FA, a New Heuristic Inverse Kinematics Solver Using Firefly Algorithm. Computational Intelligence Applications in Modeling and Control, 369-395. doi:10.1007/978-3-319-11017-2_15Buchberger, B. (2001). Multidimensional Systems and Signal Processing, 12(3/4), 223-251. doi:10.1023/a:1011949421611Kendricks, K. D. (2013). A kinematic analysis of the gmf a-510 robot: An introduction and application of groebner basis theory. Journal of Interdisciplinary Mathematics, 16(2-03), 147-169. doi:10.1080/09720502.2013.800304Wang, Y., Hang, L., & Yang, T. (2006). Inverse Kinematics Analysis of General 6R Serial Robot Mechanism Based on Groebner Base. Frontiers of Mechanical Engineering in China, 1(1), 115-124. doi:10.1007/s11465-005-0022-7Abbasnejad, G., & Carricato, M. (2015). Direct Geometrico-static Problem of Underconstrained Cable-Driven Parallel Robots With $n$ Cables. IEEE Transactions on Robotics, 31(2), 468-478. doi:10.1109/tro.2015.2393173Rameau, J.-F., & Serré, P. (2015). Computing mobility condition using Groebner basis. Mechanism and Machine Theory, 91, 21-38. doi:10.1016/j.mechmachtheory.2015.04.003Xiguang Huang, & Guangpin He. (2009). Forward kinematics of the general Stewart-Gough platform using Gröbner basis. 2009 International Conference on Mechatronics and Automation. doi:10.1109/icma.2009.5246088Uchida, T., & McPhee, J. (2012). Using Gröbner bases to generate efficient kinematic solutions for the dynamic simulation of multi-loop mechanisms. Mechanism and Machine Theory, 52, 144-157. doi:10.1016/j.mechmachtheory.2012.01.015Faugère, J.-C. (2010). FGb: A Library for Computing Gröbner Bases. 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Torii: Multipath Distributed Ethernet Fabric Protocol for Data Centers with Zero-Loss Path Repair

This paper describes and evaluates Torii, a layer-two data center network fabric protocol. The main features of Torii are being fully distributed, scalable, fault-tolerant and with automatic setup. Torii is based on multiple, tree-based, topological MAC addresses that are used for table-free forwarding over multiple equal-cost paths, and it is capable of rerouting frames around failed links on the fly without needing a central fabric manager for any function. To the best of our knowledge, it is the first protocol that does not require the exchange of periodic messages to work under normal conditions and to recover from link failures, as Torii exchanges messages just once. Moreover, another important characteristic of Torii is that it is compatible with a wide range of data center topologies. Simulation results show an excellent distribution of traffic load and latencies, similar to shortest path protocols

Torii: Multipath Distributed Ethernet Fabric Protocol for Data Centers with Zero-Loss Path Repair

This paper describes and evaluates Torii, a layer-two data center network fabric protocol. The main features of Torii are being fully distributed, scalable, fault-tolerant and with automatic setup. Torii is based on multiple, tree-based, topological MAC addresses that are used for table-free forwarding over multiple equal-cost paths, and it is capable of rerouting frames around failed links on the fly without needing a central fabric manager for any function. To the best of our knowledge, it is the first protocol that does not require the exchange of periodic messages to work under normal conditions and to recover from link failures, as Torii exchanges messages just once. Moreover, another important characteristic of Torii is that it is compatible with a wide range of data center topologies. Simulation results show an excellent distribution of traffic load and latencies, similar to shortest path protocols

On the Benefits of Channel Bonding in Dense, Decentralized Wi-Fi 4 Networks

Channel bonding is a technique first defined in the IEEE 802.11n standard to increase the throughput in wireless networks by means of using wider channels. In IEEE 802.11n (nowadays also known as Wi-Fi 4), it is possible to use 40 MHz channels instead of the classical 20 MHz channels. Although using channel bonding can increase the throughput, the classic 802.11 setting only allows for two orthogonal channels in the 2.4 GHz frequency band, which is not enough for proper channel assignment in dense settings. For that reason, it is commonly accepted that channel bonding is not suitable for this frequency band. However, to the best of our knowledge, there is not any accurate study that deals with this issue thoroughly. In this work, we study in depth the effect of channel bonding in Wi-Fi 4 dense, decentralized networks operating in the 2.4 GHz frequency band. We confirm the negative effect of using channel bonding in the 2.4 GHz frequency band with 11 channels which are 20 MHz wide (as in North America), but we also show that when there are 13 or more channels at hand (as in many other parts of the world, including Europe and Japan), the use of channel bonding yields consistent throughput improvements. For that reason, we claim that the common assumption of not considering channel bonding in the 2.4 GHz band should be revised

Libro de Actas del Primer Congreso Internacional de Análisis de Rendimiento Deportivo y Coaching

Este libro es una compliación de las Comunicaciones y Ponencias presentadas en el I Congreso Internacional de Análisis de Rendimiento Deportivo y Coaching, celebrado en la Facultad de Ciencias de la Actividad Física y el Deporte de la Universidad de Valencia entre el 25 y 27 de Marzo de 2015. Organizado por la Universidad de Valencia y la Asociación Valenciana de Análisis de Rendimiento Deportivo y Coaching.This book is a compilation of Communications and lectures presented at the Firsth International Conference on Performance Analysis and Coaching in Sport, performed in the Faculty of Physical Activity and Sport Sciences of the University of Valencia, 25-27th of March. Organized by the University of Valencia and The Valencian Association of Perfomance Analysis and Coaching in Sport

Design and evaluation of a learning environment to effectively provide network security skills

Information system security and network security are topics of increasing importance in the information society. They are also topics where the adequate education of professionals requires the use of specific laboratory environments where the practical aspects of the discipline may be addressed. However, most approaches currently used are excessively static and lack the flexibility that the education requirements of security professionals demand. In this paper we present NEMESIS, a scenario generation framework for education on system and network security, which is based on virtualization technologies and has been designed to be open, distributed, modular, scalable and flexible. Finally, an example scenario is described and some results validating the benefits of its use in undergraduate computer security courses are shown.La seguridad de redes y sistemas de información es un área de importancia creciente en el ámbito de la sociedad de información. Además, constituye un tema en el que la adecuada formación de profesionales exige el uso de entornos de laboratorio específicos en los que abordar los aspectos prácticas de la disciplina. Sin embargo, la mayoría de las aproximación usadas en la actualidad son excesivamente estáticas y carecen de la flexibilidad que las exigencias de la formación de profesionales de seguridad imponente. En este artículo, presentamos NEMESIS, un entorno para la generación de escenarios para la formación en seguridad de redes y sistemas, basado en tecnologías de virtualización que ha sido diseñado para ser abierto, distribuido, modular, escalable y flexible. Finalmente, se describe un escenario de ejemplo y se muestran resultados que validan los beneficios de su uso en cursos de seguridad informática de grad

Design and evaluation of a learning environment to effectively provide network security skills

Information system security and network security are topics of increasing importance in the information society. They are also topics where the adequate education of professionals requires the use of specific laboratory environments where the practical aspects of the discipline may be addressed. However, most approaches currently used are excessively static and lack the flexibility that the education requirements of security professionals demand. In this paper we present NEMESIS, a scenario generation framework for education on system and network security, which is based on virtualization technologies and has been designed to be open, distributed, modular, scalable and flexible. Finally, an example scenario is described and some results validating the benefits of its use in undergraduate computer security courses are shown.La seguridad de redes y sistemas de información es un área de importancia creciente en el ámbito de la sociedad de información. Además, constituye un tema en el que la adecuada formación de profesionales exige el uso de entornos de laboratorio específicos en los que abordar los aspectos prácticas de la disciplina. Sin embargo, la mayoría de las aproximación usadas en la actualidad son excesivamente estáticas y carecen de la flexibilidad que las exigencias de la formación de profesionales de seguridad imponente. En este artículo, presentamos NEMESIS, un entorno para la generación de escenarios para la formación en seguridad de redes y sistemas, basado en tecnologías de virtualización que ha sido diseñado para ser abierto, distribuido, modular, escalable y flexible. Finalmente, se describe un escenario de ejemplo y se muestran resultados que validan los beneficios de su uso en cursos de seguridad informática de grad