176 research outputs found

    Fuzzy Networked Control Systems Design Considering Scheduling Restrictions

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    Nowadays network control systems present a common approximation when connectivity is the issue to be solved based on time delays coupling from external factors. However, this approach tends to be complex in terms of time delays. Therefore, it is necessary to study the behavior of the delays as well as the integration into differential equations of these bounded delays. The related time delays needs to be known a priory but from a dynamic real-time behavior. To do so, the use of priority dynamic Priority exchange scheduling is performed. The objective of this paper is to show a way to tackle multiple time delays that are bounded and the dynamic response from real-time scheduling approximation. The related control law is designed considering fuzzy logic approximation for nonlinear time delays coupling, where the main advantage is the integration of this behavior through extended state space representation keeping certain linear and bounded behavior and leading to a stable situation during events presentation by guaranteeing stability through Lyapunov

    Fuzzy Networked Control Systems Design Considering Scheduling Restrictions

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    Nowadays network control systems present a common approximation when connectivity is the issue to be solved based on time delays coupling from external factors. However, this approach tends to be complex in terms of time delays. Therefore, it is necessary to study the behavior of the delays as well as the integration into differential equations of these bounded delays. The related time delays needs to be known a priory but from a dynamic real-time behavior. To do so, the use of priority dynamic Priority exchange scheduling is performed. The objective of this paper is to show a way to tackle multiple time delays that are bounded and the dynamic response from real-time scheduling approximation. The related control law is designed considering fuzzy logic approximation for nonlinear time delays coupling, where the main advantage is the integration of this behavior through extended state space representation keeping certain linear and bounded behavior and leading to a stable situation during events presentation by guaranteeing stability through Lyapunov

    An Implementation of Reconfigurable Network Control based upon Automata Proposal for Three Conveyor Belt Case Study

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    Online reconfiguration performed by a computer network system needs to be addressed from several perspectives due to complexity onto the system. This paper proposes different modeling approximations to obtain a holistic view of reconfiguration onto complex systems. First model is dynamic system modeling, second is an automaton in order to bound possible scenarios and third model is a Real Time scheduling algorithm to match possible configurations and related control laws

    Definition and Empirical Evaluation of Voters for Redundant Smart Sensor Systems Definición y Evaluación Empírica de Algoritmos de Voteo para Sistemas Redundantes de Sensado Inteligente

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    Abstract This study is the first attempt for integration voting algorithms with fault diagnosis devices. Voting algorithms are used to arbitrate between the results of redundant modules in fault-tolerant systems. Smart sensors are used for FDI (Fault Detection and Isolation) purposes by means of their built in intelligence. Integration of fault masking and FDI strategies is necessary in the construction of ultra-available/safe systems with on-line fault detection capability. This article introduces a range of novel software voting algorithms which adjudicate among the results of redundant smart sensors in a Triple Modular Redundant (TMR) system. Techniques to integrate replicated smart sensors and fault masking approach are discussed, and a classification of hybrid voters is provided based on result and confidence values, which affect the metrics of availability and safety.Thus, voters are classified into four groups: Independent-diagnostic safety-optimised voters, Integrated-diagnostic safety-optimised voters, Independent-diagnostic availability-optimised voters and Integrated-diagnostic availability-optimised voters. The properties of each category are explained and sample versions of each class as well as their possible application areas are discussed. Keywords: Ultra-Available System, Smart Sensor, Fault Masking, Triple Modular Redundancy. Resumen Este estudio es una primer aproximación para la integración de algoritmos de voteo con dispositivos de diagnóstico de fallas. Los algoritmos de voteo son usados para arbitrar entre los resultados de elementos redundantes en sistemas tolerantes a fallas. Los sensores inteligentes son usados para propositos de detección y separación de fallas (FDI) dada la capacidad su capacidad de inteligencia construida. La integración de enmascaramiento de fallas y las estrategias de FDI is necesaria en la construcción de sistemas altamente disponibles y seguros con la capacidad de detección de fallas en línea. Este artículo introduce un rango de algoritmos de voteo los cuales adjudican un resultado entre los resultados generados por los sensores inteligentes en un módulo de redundancia triple. Las técnicas para integrar los sensores inteligentes replicados y la aproximación de enmascaramiento de fallas son revisadas en este artículo. Una clasificación de algoritmos de voteo híbrido es provista con base en el resultado y los valores de confianza los cuales afectan las métricas de disponibilidad y seguridad de estos algoritmos. De hecho los algoritmos de voteo son clasificados en cuatro grupos: Diagnóstico-Independiente con seguridad-optimizada, Diagnóstico-Integrado con seguridad-optimizada, Diagnóstico-Independiente con disponibilidad-opitimizada y Diagnóstico-Integrado con disponibilidad-optimizada. Las propiedades de cada categoria son revisadas asi como muestras de sus implementaciones son discutidas

    Fuzzy controller to compensate comunication loads in real-time

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    [EN] A Fuzzy Resource Manager (RM) to compensate communication loads in real-time systems is presented. The design is based on a new model of a Constant Bandwidth Server (CBS), which is responsible for assigning time slots to tasks with the highest priority when idle time is available. Assuming that each application can be executed at dierent service levels, without being below a minimum limit, a fuzzy approach is introduced that allows to adjust the time resources assigned to each task and to compensate non-linearities in time resources requests. The RM increases or decreases the virtual platform for each application and assigns a maximum process time budget for it, which is gradually used and refilled when depleted, without aecting the other applications. The scheme self-adjusts to sudden changes in applications process time requirements.[ES] Se presenta un administrador de recursos (RM) difuso para compensar las cargas de comunicación en sistemas en tiempo real. El diseño del RM se basa en un nuevo modelo de Servidor de Ancho de Banda Constante (CBS) que se encarga, a través de una plataforma virtual, de asignar tiempo de proceso a las tareas de mayor prioridad cuando existe capacidad disponible. Si se asume que cada aplicación puede ser ejecutada con diferentes niveles de servicio sin que este esté por debajo de un límite mínimo, se propone una aproximación difusa que permite actualizar de manera gradual los tiempos de proceso asignados a cada tarea. Esta aproximación permite compensar el comportamiento no lineal en las solicitudes de tiempo de proceso. El RM aumenta o disminuye la plataforma virtual para cada aplicación y le asigna un presupuesto máximo de tiempo de proceso, mismo que la aplicación usa gradualmente y que se reasigna al agotarse, sin por ello afectar el desempeño del resto de las aplicaciones. El esquema se auto-ajusta cuando ocurren a cambios repentinos en los requerimientos de tiempo de proceso de las aplicaciones.Este trabajo ha sido realizado parcialmente gracias al apoyo del CONACYT BECA 597175, PAPIIT IT100320 y PAPIIT IN104516.Aparicio-Santos, J.; Hermosillo-Gómez, J.; Benítez-Pérez, H.; Álvarez-Icaza, L. (2021). Controlador difuso para compensar cargas de comunicación en sistemas en tiempo real. Revista Iberoamericana de Automática e Informática industrial. 18(3):288-299. https://doi.org/10.4995/riai.2021.14544OJS288299183Abeni, L., Buttazzo, G., Dec 1998. Integrating multimedia applications in hard real-time systems. In: Proceedings 19th IEEE Real-Time Systems Symposium (Cat. No.98CB36279). pp. 4-13. https://doi.org/10.1109/REAL.1998.739726Aparicio, Santos, J. A., 2017. Diseño de un controlador difuso para compensar cargas de comunicación en tiempo real. Master's thesis, Universidad Nacional Autónoma de México, México.Bini, E., Buttazzo, G., Eker, J., Schorr, S., Guerra, R., Fohler, G., Arzen, K. E., Romero, V., Scordino, C., May 2011. Resource management on multicore systems: The actors approach. IEEE Micro 31 (3), 72-81. https://doi.org/10.1109/MM.2011.1Boutalis, Y., Theodoridis, D., Kottas, T., Christodoulou, M. A., 2014. System Identification and Adaptive Control: Theory and Applications of the Neurofuzzy and Fuzzy Cognitive Network Models. Springer.Buttazzo, G. C., 2011. Hard Real-Time Computing Systems: Predictable Scheduling Algorithms and Applications, 3rd Edition. Springer Publishing Company, Incorporated. Byeong Gi, L., Daeyoung, P., Hanbyul, S., 2009. Wireless Communications Resource Managemen. John Wiley and Sons.Byeong Gi, L., Daeyoung, P., Hanbyul, S., 2009. Wireless Communications Resource Managemen. John Wiley and Sons.Chasparis, G., Maggio, M., Arzen, K. E., Bini, E., June 2013. Distributed management of cpu resources for time-sensitive applications. In: 2013 American Control Conference. pp. 5305-5312. https://doi.org/10.1109/ACC.2013.6580666Chasparis, G. C., Maggio, M., Bini, E., Arzen, K.-E., 2016. Desing and implementation of distributed resource management for time-sensitive applications. Automatica 64, 44 - 53. https://doi.org/10.1016/j.automatica.2015.09.015Clark, R. K., 1990. Scheduling dependent real-time activities. Ph.D. thesis, USA, aAI9107552.Ganz, A., Ganz, Z., Wongthavarawat, K., 2003. Multimedia Wireless Networks: Technologies, Standards and QoS. Pearson Education.Horn, W., 1974. Some simple scheduling algorithms. Naval Research Logistics Quarterly 21 (1), 177-185. https://doi.org/10.1002/nav.3800210113IEEE Standard Glossary of Software Engineering Terminology. https://doi.org/10.1109/IEEESTD.1990.101064Litoiu, M., Tadei, R., 2001. Fuzzy scheduling with application to real-time systems. Fuzzy Sets and Systems 121 (3), 523 - 535. https://doi.org/10.1016/S0165-0114(99)00176-1Mahmoud, M., of Engineering, I., Technology, 2013. Distributed Control and Filtering for Industrial Systems. Control, Robotics and Sensors. Institution of Engineering and Technology. URL: https://books.google.com.mx/books?id=qWhWx2hRLYcC https://doi.org/10.1049/PBCE088EMok, A. K., Feng, X., May 2001. Resource partition for real-time systems. In: Proceedings Seventh IEEE Real-Time Technology and Applications Symposium. pp. 75-84. https://doi.org/10.1109/RTTAS.2001.929867Nesbit, K. J., Moreto, M., Cazorla, F. J., Ramirez, A., Valero, M., Smith, J. E., May 2008. Multicore resource management. IEEE Micro 28 (3), 6-16. https://doi.org/10.1109/MM.2008.43Quanser, 2012. USER MANUAL 3 DOF Gyroscope Experiment Set Up and Configuration. Quanser inc.Robert H. Cannon, J., 2003. Dynamics Of Physical Systems. Dover Publications, INC.Stankovic, J. A., 1988. Misconceptions about real-time computing: a serious problem for next-generation systems. Computer 21 (10), 10-19. https://doi.org/10.1109/2.7053Subrata, R., Zomaya, A. Y., Landfeldt, B., Oct 2008. A cooperative game framework for qos guided job allocation schemes in grids. IEEE Transactions on Computers 57 (10), 1413-1422. https://doi.org/10.1109/TC.2008.79Tanaka, K., Ikeda, T., Wang, H. O., May 1998. Fuzzy regulators and fuzzy observers: relaxed stability conditions and lmi-based designs. IEEE Transactions on Fuzzy Systems 6 (2), 250-265. https://doi.org/10.1109/91.66902

    Design of a Fuzzy Networked Control Systems. Priority Exchange Scheduling Algorithm

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    This work presents a supervisory control strategy for Networked Control Systems (NCSs). This shows the identification and control of the plant using fuzzy theory. The fuzzy model incorporates the delay dynamics within the fuzzy rules based upon a real-time hierarchical scheduling strategy. A hierarchical scheduling Priority Exchange algorithm is used based upon codesign strategy following mutual correlation among control and network algorithms in order to bounded time delays. A system of magnetic levitation is presented as a case study

    The role of the LIRG and ULIRG phases in the evolution of Ks-selected galaxies

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    We investigate the role of the luminous infrared galaxy (LIRG) and ultra-luminous infrared galaxy (ULIRG) phases in the evolution of Ks-selected galaxies and, in particular, Extremely Red Galaxies (ERGs). With this aim, we compare the properties of a sample of 2905 Ks<21.5 (Vega mag) galaxies in the GOODS/CDFS with the sub-sample of those 696 sources which are detected at 24 microns. We find that LIRGs constitute 30% of the galaxies with stellar mass M>1x10^{11} Msun assembled at redshift z=0.5. A minimum of 65% of the galaxies with M>2.5x10^{11} Msun at z~2-3 are ULIRGs at those redshifts. 60% of the ULIRGs in our sample have the characteristic colours of ERGs. Conversely, 40% of the ERGs with stellar mass M>1.3x10^{11} Msun at 1.5<z<2.0 and a minimum of 52% of those with the same mass cut at 2.0<z<3.0 are ULIRGs. The average optical/near-IR properties of the massive ERGs at similar redshifts that are identified with ULIRGs and that are not have basically no difference, suggesting that both populations contain the same kind of objects in different phases of their lives. LIRGs and ULIRGs have an important role in galaxy evolution and mass assembly, and, although they are only able to trace a fraction of the massive (M>1x10^{11} Msun) galaxies present in the Universe at a given time, this fraction becomes very significant (>50%) at redshifts z>~2.Comment: Accepted for publication in A&A. 9 pages, 6 figure

    Fuzzy Control Design for a Class of Nonlinear Network Control System: Helicopter Case Study

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    This paper presents a fuzzy control approach to a helicopter MIMO nonlinear system, implemented on a Networked Control System, as case study. For this, a hardware-in-the-Loop implementation is developed using several multi-channel A/D Cards, integrated to a computer network system. Variant time delays are considered over Ethernet and CANBUS networks. Fuzzy logic is used to deal with the complexity of the integrated computer network as well as with the dynamics of the system. Two fuzzy logic control systems are coupled for both signals of the helicopter case study: yaw and pitch. Both these tend to concentrate around desired references, considering variant time delays
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