90,990 research outputs found

    Distributed sensor architecture for intelligent control that supports quality of control and quality of service

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    This paper is part of a study of intelligent architectures for distributed control and communications systems. The study focuses on optimizing control systems by evaluating the performance of middleware through quality of service (QoS) parameters and the optimization of control using Quality of Control (QoC) parameters. The main aim of this work is to study, design, develop, and evaluate a distributed control architecture based on the Data-Distribution Service for Real-Time Systems (DDS) communication standard as proposed by the Object Management Group (OMG). As a result of the study, an architecture called Frame-Sensor-Adapter to Control (FSACtrl) has been developed. FSACtrl provides a model to implement an intelligent distributed Event-Based Control (EBC) system with support to measure QoS and QoC parameters. The novelty consists of using, simultaneously, the measured QoS and QoC parameters to make decisions about the control action with a new method called Event Based Quality Integral Cycle. To validate the architecture, the first five Braitenberg vehicles have been implemented using the FSACtrl architecture. The experimental outcomes, demonstrate the convenience of using jointly QoS and QoC parameters in distributed control systems.The study described in this paper is a part of the coordinated project COBAMI: Mission-based Hierarchical Control. Education and Science Department Spanish Government. CICYT: MICINN: DPI2011-28507-C02-01/02 and project "Real time distributed control systems" of the Support Program for Research and Development 2012 UPV (PAID-06-12).Poza-Lujan, J.; Posadas-Yagüe, J.; Simó Ten, JE.; Simarro Fernández, R.; Benet Gilabert, G. (2015). Distributed sensor architecture for intelligent control that supports quality of control and quality of service. Sensors. 15(3):4700-4733. https://doi.org/10.3390/s150304700S4700473315

    Asynchronous real-time ethernet

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    The Industrial Ethernet has become a way to build distributed systems in industrial networks which must provide predictable performance and maintainability. Industrial applications require time-critical processing, which can be guaranteed within soft or hard real-time environments, Where applications' responses require deterministic processing time, the hard real-time environment is requested. The Fieldbus protocols are the standard way to connect instruments on the Ethernet-based communication. Fieldbuses require synchronisation and dedicated application-specific integrated circuits, what leaves space for alternate, more common solutions. This thesis presents design, implementation, and evaluation of the novel Real-Time Driver Model asynchronous communication stack called 61850CS API. 61850CS stack is implemented in an intelligent electronic device to enable real-time IEC 61850 GOOSE Ethernet communications in electrical substations. The presented 61850CS implementation enables simultaneous flow of real-time and non-real-time Ethernet traffic over the same physical network interface controller. The same technology supports running arbitrary real-time Ethernet traffic and non real-time Ethernet traffic simultaneously and its implementation is general enough to enable an API use on different architectures and to comply with different industrial Ethernet requirements. And more, since 61850CS doesn't affect CSMA/CD mechanism, it doesn't need any master nodes, which increases the system availability. The presented solution was implemented as an application programming interface for feeder protection and control (FPC 680) intelligent electronic device relay. Hardware platform for 61850CS was PPC440EPx microcontroller with implemented Linux Real-Time application interface RTOS. The FPC 680 is an IED commercial product by Iskra d.d. which is implemented worldwide in several substations

    Asynchronous real-time ethernet

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    The Industrial Ethernet has become a way to build distributed systems in industrial networks which must provide predictable performance and maintainability. Industrial applications require time-critical processing, which can be guaranteed within soft or hard real-time environments, Where applications' responses require deterministic processing time, the hard real-time environment is requested. The Fieldbus protocols are the standard way to connect instruments on the Ethernet-based communication. Fieldbuses require synchronisation and dedicated application-specific integrated circuits, what leaves space for alternate, more common solutions. This thesis presents design, implementation, and evaluation of the novel Real-Time Driver Model asynchronous communication stack called 61850CS API. 61850CS stack is implemented in an intelligent electronic device to enable real-time IEC 61850 GOOSE Ethernet communications in electrical substations. The presented 61850CS implementation enables simultaneous flow of real-time and non-real-time Ethernet traffic over the same physical network interface controller. The same technology supports running arbitrary real-time Ethernet traffic and non real-time Ethernet traffic simultaneously and its implementation is general enough to enable an API use on different architectures and to comply with different industrial Ethernet requirements. And more, since 61850CS doesn't affect CSMA/CD mechanism, it doesn't need any master nodes, which increases the system availability. The presented solution was implemented as an application programming interface for feeder protection and control (FPC 680) intelligent electronic device relay. Hardware platform for 61850CS was PPC440EPx microcontroller with implemented Linux Real-Time application interface RTOS. The FPC 680 is an IED commercial product by Iskra d.d. which is implemented worldwide in several substations

    Design and implementation of a modular controller for robotic machines

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    This research focused on the design and implementation of an Intelligent Modular Controller (IMC) architecture designed to be reconfigurable over a robust network. The design incorporates novel communication, hardware, and software architectures. This was motivated by current industrial needs for distributed control systems due to growing demand for less complexity, more processing power, flexibility, and greater fault tolerance. To this end, three main contributions were made. Most distributed control architectures depend on multi-tier heterogeneous communication networks requiring linking devices and/or complex middleware. In this study, first, a communication architecture was proposed and implemented with a homogenous network employing the ubiquitous Ethernet for both real-time and non real-time communication. This was achieved by a producer-consumer coordination model for real-time data communication over a segmented network, and a client-server model for point-to-point transactions. The protocols deployed use a Time-Triggered (TT) approach to schedule real-time tasks on the network. Unlike other TT approaches, the scheduling mechanism does not need to be configured explicitly when controller nodes are added or removed. An implicit clock synchronization technique was also developed to complement the architecture. Second, a reconfigurable mechanism based on an auto-configuration protocol was developed. Modules on the network use this protocol to automatically detect themselves, establish communication, and negotiate for a desired configuration. Third, the research demonstrated hardware/software co-design as a contribution to the growing discipline of mechatronics. The IMC consists of a motion controller board designed and prototyped in-house, and a Java microcontroller. An IMC is mapped to each machine/robot axis, and an additional IMC can be configured to serve as a real-time coordinator. The entire architecture was implemented in Java, thus reinforcing uniformity, simplicity, modularity, and openness. Evaluation results showed the potential of the flexible controller to meet medium to high performance machining requirements

    Consciosusness in Cognitive Architectures. A Principled Analysis of RCS, Soar and ACT-R

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    This report analyses the aplicability of the principles of consciousness developed in the ASys project to three of the most relevant cognitive architectures. This is done in relation to their aplicability to build integrated control systems and studying their support for general mechanisms of real-time consciousness.\ud To analyse these architectures the ASys Framework is employed. This is a conceptual framework based on an extension for cognitive autonomous systems of the General Systems Theory (GST).\ud A general qualitative evaluation criteria for cognitive architectures is established based upon: a) requirements for a cognitive architecture, b) the theoretical framework based on the GST and c) core design principles for integrated cognitive conscious control systems

    Intelligent systems for active vibration control in flexible engineering structures / by Ji Xiaoxu.

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    Vibration arises in almost all moving structures. Vibration control is important to many applications such as robotic arms, aircraft wings, buildings in wind, vehicle transmission systems,to name but a few. The objective of this thesis is to develop more efficient intelligent controllers for vibration suppression, mainly for time-varying flexible structures. At first, based on TSO and TSl fuzzy models, novel neural-fuzzy (NF) controllers are developed for active vibration control of the flexible structures. The NF control paradigms are intended to integrate the advantages from both fuzzy logic and neural networks while overcoming their respective limitations. The control reasoning is undertaken by fuzzy logic whereas the fuzzy control system is optimized by neural network related training algorithms. A new strategy is suggested to simplify the architectures of the classical NF controllers so as to make the control process computationally efficient for real-time applications. A recurrent identification network (RIN) is developed to adaptively identify system dynamics of the timevarying flexible structures. When system dynamics (e.g., mass, stiffness, and damping) varies, the proposed RIN and NF controller can effectively recognize the system’s new dynamics and perform corresponding control operations. A novel hybrid training technique based on real time recurrent learning (RTRL) and least square estimate (LSE) is suggested for real-time training of the RIN scheme to optimize its nonlinear input-output mapping. The effectiveness of the developed intelligent controllers and the related techniques has been verified by online experimental tests of corresponding fixed and time-varying dynamic conditions. Test results have shown that the developed adaptive NF controller outperforms the classical controllers (e.g., PD) and other related intelligent control strategies

    Survey of dynamic scheduling in manufacturing systems

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    A New Constructivist AI: From Manual Methods to Self-Constructive Systems

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    The development of artificial intelligence (AI) systems has to date been largely one of manual labor. This constructionist approach to AI has resulted in systems with limited-domain application and severe performance brittleness. No AI architecture to date incorporates, in a single system, the many features that make natural intelligence general-purpose, including system-wide attention, analogy-making, system-wide learning, and various other complex transversal functions. Going beyond current AI systems will require significantly more complex system architecture than attempted to date. The heavy reliance on direct human specification and intervention in constructionist AI brings severe theoretical and practical limitations to any system built that way. One way to address the challenge of artificial general intelligence (AGI) is replacing a top-down architectural design approach with methods that allow the system to manage its own growth. This calls for a fundamental shift from hand-crafting to self-organizing architectures and self-generated code – what we call a constructivist AI approach, in reference to the self-constructive principles on which it must be based. Methodologies employed for constructivist AI will be very different from today’s software development methods; instead of relying on direct design of mental functions and their implementation in a cog- nitive architecture, they must address the principles – the “seeds” – from which a cognitive architecture can automatically grow. In this paper I describe the argument in detail and examine some of the implications of this impending paradigm shift

    The Staging Transformation Approach to Mixing Initiative

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    Mixed-initiative interaction is an important facet of many conversational interfaces, flexible planning architectures, intelligent tutoring systems, and interactive information retrieval systems. Software systems for mixed-initiative interaction must enable us to both operationalize the mixing of initiative (i.e., support the creation of practical dialogs) and to reason in real-time about how a flexible mode of interaction can be supported (e.g., from a meta-dialog standpoint). In this paper, we present the staging transformation approach to mixing initiative, where a dialog script captures the structure of the dialog and dialog control processes are realized through generous use of program transformation techniques (e.g., partial evaluation, currying, slicing); this allows control to be cast as the process of moving from one dialog script to another. In this approach, operationalizing mixed-initiative interaction becomes the task of finding a suitable program transformation to stage the interaction between the two participants. We highlight the advantages of this approach and present its realization in various modalities for information seeking dialogs. We also outline how high-level reasoning capabilities about dialogs can be provided in the staging transformation framework

    Precise vehicle location as a fundamental parameter for intelligent selfaware rail-track maintenance systems

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    The rail industry in the UK is undergoing substantial changes in response to a modernisation vision for 2040. Development and implementation of these will lead to a highly automated and safe railway. Real-time regulation of traffic will optimise the performance of the network, with trains running in succession within an adjacent movable safety zone. Critically, maintenance will use intelligent trainborne and track-based systems. These will provide accurate and timely information for condition based intervention at precise track locations, reducing possession downtime and minimising the presence of workers in operating railways. Clearly, precise knowledge of trains’ real-time location is of paramount importance. The positional accuracy demand of the future railway is less than 2m. A critical consideration of this requirement is the capability to resolve train occupancy in adjacent tracks, with the highest degree of confidence. A finer resolution is required for locating faults such as damage or missing parts, precisely. Location of trains currently relies on track signalling technology. However, these systems mostly provide an indication of the presence of trains within discrete track sections. The standard Global Navigation Satellite Systems (GNSS), cannot precisely and reliably resolve location as required either. Within the context of the needs of the future railway, state of the art location technologies and systems were reviewed and critiqued. It was found that no current technology is able to resolve location as required. Uncertainty is a significant factor. A new integrated approach employing complimentary technologies and more efficient data fusion process, can potentially offer a more accurate and robust solution. Data fusion architectures enabling intelligent self-aware rail-track maintenance systems are proposed
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