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This paper, is an application in the area of automatic control with artificial neural networks, for control of the pressure of a tank in the ethanol plant; with an algorithm deadbeat; with previously is realized calculus of coefficients of the neural network in method off line. The weights was calculates for the network backprogation, are explained the proceedings for the net and algorithm control, the results of real time control; the calculus of coefficient of net is realized with Matlab and control in C++. This technical of control utilizing neural networks is a good help instrument for resolved the problems of stabilizing and velocity. [ABSTRACT FROM PUBLISHER]

Abstract: The revision of the conventional Magnitude Optimum design criterion for tuning the PID type controller''s parameters reveals three fundamental drawbacks. These drawbacks restrict the PID controller''s optimal tuning in terms of robustness and disturbance rejection at the output of the controlled process. Specifically (1) the conventional PID tuning via the Magnitude Optimum criterion restricts the controller''s zeros to be tuned only with real values, (2) for determining the PID controller''s zeros, exact pole-zero cancellation has to be achieved between the process''s poles and the controller''s zeros and (3) the conventional design procedure via the Magnitude Optimum criterion has been tested only to a limited class of simple process models. To overcome the aforementioned drawbacks a revised PID type control law is proposed in this work. For the development of the control law a general transfer function of the process model is employed in the frequency domain. The final control law consists of analytical expressions that involve all modelled process parameters. The resulting control law can be applied directly to any linear Single Input Single Output stable process regardless of its complexity. For evaluating the proposed theory, an extensive simulation test batch between the conventional and the revised PID tuning is performed for various benchmark processes. Throughout this evaluation, the validity of several literature comments related to the Magnitude Optimum criterion is discussed. Finally, it is shown that the performance of the proposed control law compared to the conventional PID design procedure achieves satisfactory results both in the time and the frequency domain, in terms of robustness and disturbance rejection. [Copyright &y& Elsevier]

Abstract: An extension of the Symmetrical Optimum criterion for the design of PID type-p closed- loop control systems is proposed. Type-p control loops are characterized by the presence of p integrators in the open-loop transfer function. For designing a PID type-p control loop there should exist an PI p D, or PI(p−1)D, or PID and so on, if the controlled process is of type-0 or type-1 or type-(p −1) respectively. A type-II control loop achieves zero steady state position and velocity error, a type-III control loop achieves zero steady state position, velocity and acceleration error and therefore a type-p control loop is expected to track both faster reference signals and eliminate higher order errors at steady state. For deriving the proposed control law, a transfer function containing dominant time constants and the plant''s unmodelled dynamics has been considered in the frequency domain. The final control law consists of analytical expressions that involve both dominant dynamics and model uncertainty of the controlled process. For justifying the potential of the proposed theory, simulation results for representative processes met in many industry applications are presented. [Copyright &y& Elsevier]

Abstract: Despite the many studies that have attempted to develop “friendly” methods for industrial controller programming, they are still programmed by conventional “trial-and-error” methods and in practice, there is little written documentation on these systems. The ideal solution is to use a computational environment that allows industrial engineers to implement the system using high-level language and that follows international standards. Accordingly, this paper proposes a methodology to model and validate control programs for manufacturing systems that include sequential, parallel and timed operations, using a formalism based on Statecharts, denominated Basic Statechart (BSC). To improve the formal aspects of the original Statecharts, we introduce the semantic of the BSC using only characteristics relevant to the industrial area. We also present an algorithm that translates the control model described in BSC into Ladder diagrams, thereby enabling tests with actual PLCs. Finally, one typical example of application in the manufacturing area is discussed as case study to illustrate the proposed methodology. [Copyright &y& Elsevier]

This paper describes an emerging tool for industry: fractional order systems. Conventional understanding of the notion of derivative and integral uses integer orders and our sense is mature in their physical interpretations. Derivatives or integrals of fractional orders are generalizations of the concept containing the classical cases and solutions based on fractional order operators utilize the full flexibility offered by the mathematical definitions. The interest of the industry to fractional order systems lie in the fact that complicated modules can be simplified significantly and practical applications can be diverse. This paper describes linear and nonlinear cases with necessary stability and performance considerations for the benefit of a practicing engineer exploiting informatics in industry. [ABSTRACT FROM PUBLISHER]

The adoption of open-source operating systems for the execution of real-time applications is gaining popularity, even in the networked control systems domain, due to cost and flexibility reasons. However, as opposed to their commercial counterparts, the actual performance level to be expected from them is still little known and may often depend on the kind of real-time extension being used, its configuration, and the overall software load of the system, including best-effort components. [ABSTRACT FROM PUBLISHER]

In this paper, Generalized Multiprotocol Label Switching (GMPLS) controlled optical networks are considered as industry communication network. GMPLS is a Next-Generation Network technology which will be used to build new Internet backbone. Thanks to the features of a new public network, Internet can become a platform for industrial communication including critical data, transactional flow, and real-time data. The benefits of such a network for industry are explained in this paper. Next, the idea and architecture of intelligent, next-generation optical transport networks is discussed and explained. One of the challenges of GMPLS technology is a reliability as the main factor which influences service quality. Therefore, the method of improving reliability of GMPLS is proposed. This method bases on the implementing of redundancy in the control plane. Using Monte Carlo simulation and proposed reliability analysis method quantity improvement of GMPLS network reliability is shown and the merits of using this method are confirmed. Achieved simulation results and analysis confirm also that this emerging optical transport network will offer industry long distance communication with transmission condition compared to what is provided by dedicated WAN links. Simultaneously using public infrastructure can reduce cost of long distance communication. [ABSTRACT FROM PUBLISHER]

This paper deals with distributed multiagent reconfigurable embedded-control systems following the component-based International Industrial Standard IEC61499 in which a function block (FB) is an event-triggered software component owning data and a control application is a distributed network of FBs. We define an architecture of reconfigurable multiagent systems, where a reconfiguration agent modeled by nested state machines is affected to each device of the execution environment to apply local automatic reconfigurations, and a coordination agent is proposed for any coordination between devices in order to guarantee safe and adequate distributed reconfigurations. A communication protocol is proposed in our research to handle coordinations between agents by using well-defined coordination matrices. We define, in addition, Extensible Markup Language (XML) based implementations for both kinds of agents, where XML code blocks are exchanged between devices. The contributions of the paper are applied to two benchmark production systems available in our laboratory. [ABSTRACT FROM PUBLISHER]

The aim of this paper is to review the state-of-the-art of Field Programmable Gate Array (FPGA) technologies and their contribution to industrial control applications. Authors start by addressing various research fields which can exploit the advantages of FPGAs. The features of these devices are then presented, followed by their corresponding design tools. To illustrate the benefits of using FPGAs in the case of complex control applications, a sensorless motor controller has been treated. This controller is based on the Extended Kalman Filter. Its development has been made according to a dedicated design methodology, which is also discussed. The use of FPGAs to implement artificial intelligence-based industrial controllers is then briefly reviewed. The final section presents two short case studies of Neural Network control systems designs targeting FPGAs. [ABSTRACT FROM PUBLISHER]

This paper is concerned with the modeling of a plastic film manufacturing process and the development and implementation of a model-based Cross-Directional (CD) controller. The model is derived from first-principles and some empirical relationships. The final validated nonlinear model could provide a useful offline platform for developing control and monitoring algorithms. [ABSTRACT FROM PUBLISHER]

User-specified benchmark has been used for control loop performance assessment. Structured closed-loop responses which are subject to various performance characteristics constraints are proposed in this work and served as a user-specified benchmarks against which the existing controller performance is compared. The performance characteristics constraints can be a mixture of variance upper bound, pole location, peak amplitude and model approximation constraint. An linear matrix inequality-based approach is used to formulate this multi-objective problem and a cone complementarity linearization algorithm is applied to find an optimal solution. Simulation studies and experimental results are provided to demonstrate application of the proposed benchmarks. [ABSTRACT FROM PUBLISHER]

In order to develop more effective decoupling control methods for complex coupling system, we present an intelligent bi-cooperative decoupling controller (IBCDC) inspired from the modulation mechanism of internal environment in body. The IBCDC consists of a coordination control unit (CCU), a model identification unit (MIU), a decoupling control evaluation unit (DEU), and two control units. The DEU includes a reinforcing decoupling control block (RDCB) and a suppression decoupling control block (SDCB). Every control unit or block including an original control block (OCB) and a decoupling compensation block (DCB) is designed according to different physiological organs or systems. Under the coordination of the CCU, all the control units or blocks communicate with each other to exchange the control or decoupling control information. Through adjusting the actuators harmoniously, the coupling influences among different control loops can be reduced or almost eliminated. The simulation results demonstrate that the IBCDC can almost eliminate the coupling influence with better control performance. Compared with other decoupling control methods, the IBCDC can be implemented more easily and practically, and be easily generalized to the multiple-input–multiple-output systems. [ABSTRACT FROM PUBLISHER]

As fieldbus networks are becoming accessible from the Internet, security mechanisms to grant access only to authorized users and to protect data are becoming essential. This paper proposes a formally based approach to the analysis of such systems, both at the security protocols level and at the system architecture level. This multilevel analysis allows the evaluation of the effects of an attack on the overall system, due to security problems that affect the underlying security protocols. A case study on a typical fieldbus security system validates the approach. [ABSTRACT FROM PUBLISHER]

Abstract: This paper illustrates the benefits of a multivariable linearizing control approach applied to an industrial crystallization process. This relevant approach proposes a setpoint tracking for the crystal mass/concentration couple. In this purpose, a model dedicated to last stage crystallization is designed, without consideration of crystal size distribution. The controlled variables, unavailable, are obtained using an extended Luenberger observer. The observer is validated on industrial data and shows good performance in both convergence rate and accuracy. The performance of the proposed linearizing strategy, which application to cane sugar crystallization constitutes a real novelty, is tested via simulation. The good performance in setpoint tracking, even in presence of noise, disturbances and modeling error, allows to consider a significant improvement of the global productivity. [ABSTRACT FROM AUTHOR]

The industry of machine tools keeps a constant progress that responds to the most demanding market requirements, such as production-time decreasing and zero-defect manufacturing. As part of this progress, sensors and monitoring instruments have been integrated on machine tools, improving computer numerical control (CNC) and monitoring during the manufacturing process. The vibrations are one of the most significant variables to be monitored on machine tools since they directly affect the end piece finishing, tool life expectancy, general machine-tool condition, current consumption, etc. Time domain, fast Fourier transform (FFT), and discrete wavelet transform (DWT) are techniques often used for vibration analysis, because they are computationally efficient for online implementation; unfortunately, it is difficult to find an instrument for vibration analysis that allows individually applying the time, FFT, and DWT techniques, and their fusion. Moreover, the lack of instruments with characteristics such as open architecture, low cost, parallel processing, and continuous online monitoring is remarkable. The contribution of this work consists of developing a vibration-analysis instrument based on the time, FFT, DWT, and DWT-FFT fusion techniques. The instrument is implemented into a low-cost field-programmable gate array with proprietary hardware signal-processing cores in parallel for achieving real-time and continuous online analysis. Experimentation is done to show the proposed methodology efficiency and the developed-instrument versatility, focusing on industrial control applications for CNC machine tools. [ABSTRACT FROM PUBLISHER]

Wireless sensor and actuator networks (WSANs) bring many benefits to industrial automation systems. When a control system is integrated by a WSAN, and particularly if the network scale is large, distributed communication and control methods are quite necessary. However, unreliable wireless and multihop communications among sensors and actuators cause challenges in designing such systems. This paper proposes and evaluates a new distributed estimation and collaborative control scheme for industrial control systems with WSANs. Extensive results show that the proposed method effectively achieves control objectives and maintains robust against inaccurate system parameters. We also discuss how to dynamically extend the scale of a WSAN with only local adjustments of sensors and actuators. [ABSTRACT FROM PUBLISHER]

When adequately maintained, the mechanical system of rewinders and similar machines in paper industry may have a significantly longer service life than its electrical and control systems. Over the lifetime of the facility, a rewinder may experience several major maintenance cycles, and these generally include significant upgrades to the electrical drive and control system. These upgrades present an opportunity to modify the design of the control system to eliminate some of the sensors or to provide signal redundancy by using state estimation. During such major reconstruction of a paper-board rewinder, it was noticed that the shipping-roll radius and the web tension force can be accurately estimated from the measurements available within the drive's control system. This paper presents the implementation of the two estimators on a commercial production rewinder. Test results from the equipment in service show that the measured signals can be supplemented with the estimated ones to provide an alternative in the event of sensor malfunction or to enable trending of accuracy of calibration. Both applications have an entitlement to reduce the downtime of the rewinder, as the replacement of the faulted sensor can be scheduled for the next planned idle period of the machine. [ABSTRACT FROM AUTHOR]

It is a recent trend to consider wireless sensor networks in harsh industrial environments. With actual deployment of wireless sensor networks, it would be desirable to make a concrete deployment plan regarding connectivities and to place sensors by grouping them according to the planned deployment points, even more in case of targeting multiple objects to be sensed and monitored in harsh environments. The connectedness of groups as well as individual sensors is important specifically for real-time data acquisitions and even more if there are no external communication links among these groups. In this paper, we focus on the connectivity of sensor groups, rather than the individual sensors only, and propose a novel group connectivity model so as to analyze group connectivity and to make a concrete deployment plan of sensor groups with regard to the internal distribution of sensors and group positions. We believe that the proposed model should be useful in planning the deployment of wireless sensor networks in harsh industrial environments where running wires is less practical and also prohibitively expensive. [ABSTRACT FROM AUTHOR]

• Industrial printing applications demand higher throughput in-line digital laser marking. • Single laser beam sequential processing limits marking speed to 8 m/s (de facto barrier). • A laser beam matrix controlled by embedded computing overcomes marking speed barriers. • Images of 50–200 dpi resolution, 6–50 mm width, speed up to 16 m/s can be printed. • Even higher speeds can be achieved by investing in additional laser beams. The creation of visible changes marked onto object surfaces by laser has become an effective way of coding industrial products. Industrial applications for printing solutions drive the demand for higher speed and higher throughput for in-line digital laser marking. Currently, most laser marking equipment is based on a single laser beam with the corresponding sequential processing that culminates in a performance bottleneck which limits printing production line speed to a de facto barrier of 8 m/s. In this paper, we present a system that overcomes this barrier by using a matrix of laser beams controlled by an embedded high-performance computing platform. The industrialized solutions presented in this paper can print images of 50 to 200 dpi resolution on printing substrates widths ranging from 6 mm to 50 mm, at product line speeds of up to 16 m/s. The analysis we have performed suggests that even higher speeds could be achieved by investing in additional laser beams. [ABSTRACT FROM AUTHOR]

In a context of energy abundance for industrial applications, industrial systems are exploited with minimal attention to their actual energy consumption requirements to meet the loads imposed on them. As a result, most of them are used at maximal capacity, regardless of the varying operational conditions. First, the paper studies pneumatic conveying systems and thoroughly reviews previously published work. Then, we overview simulations and operating data of the experimental parameters and their effects on the flow characteristics and transport efficiency. Finally, we summarize with a conclusion and some suggestions for further work. The primary goal of this study is to identify the parameters that influence the energy consumption of industrial dust collector systems. It is differentiated from previously published overviews by being concentrated on wood particles collection systems. The results will permit a better selection of an appropriate methodology or solution for reducing an industrial system's power requirements and energy consumption through more precise control. The anticipated benefits are not only on power requirement and energy consumption but also in reducing greenhouse gas emissions. This aspect shows more impacts in regions that rely on electricity supplied by thermal power stations, especially those that use petrol or coal. [ABSTRACT FROM AUTHOR]

Fault tolerance is an important aspect in real-time computing. In real-time control systems, tasks could be faulty due to various reasons. Faulty tasks may compromise the performance and safety of the whole system and even cause disastrous consequences. In this paper, we describe On-demand real-time guard (ORTEGA), a new software fault tolerance architecture for real-time control systems. ORTEGA has high fault coverage and reliability. Compared with existing real-time fault tolerance architectures, such as Simplex, ORTEGA allows more efficient resource utilizations and enhances flexibility. These advantages are achieved through the on-demand detection and recovery of faulty tasks. ORTEGA is applicable to most industrial control applications where both efficient resource usage and high fault coverage are desired. [ABSTRACT FROM PUBLISHER]

The main propose of this project is to design a multi-agent system platform on a flexible manufacturing cell (FMC). Taking into consideration all levels of functional issues, cellular architecture, standardization, and technical configurations, we take advantage of features released on a graphical programming commercial software, such as object oriented programming, distributed intelligence, and block function representation. The approach is addressed to encourage the usage of holonic and multiagent concepts in traditional manufacturing systems, with friendly software based upgrade and a minimum low cost hardware expansion. The intention is to develop a system that will fit into different levels of an enterprise, including shop-floor and manufacturing execution systems, and simultaneously we will deal with technological migration from conventional manufacturing structure to a holonic-ready FMC. [ABSTRACT FROM PUBLISHER]

This article describes the features and development of intelligent machines and concentrates on their information processing infrastructure. IEC 61499 function blocks have been used in these experiments as the driving vehicle to achieve important features of the intelligent machines such as reconfigurability. Information infrastructure of intelligent machines is based on the IEC 61499 architecture . The function block architecture of IEC 61499 provides a new degree of flexibility in managing embedded control and information processing systems through the lifetime of industrial automation products. The requirements of flexible manufacturing and material handling systems, such as rapid integration and reconfiguration, as well as the growing information intensity of the production environments imply that manufacturing equipment is becoming more autonomous and intelligent. [ABSTRACT FROM PUBLISHER]

Abstract: This paper is aimed at summarizing the current state-of-the-art in the development of agent-based solutions in three areas connected with industrial production, namely in holonic control, production management and virtual enterprises. This paper shows how the results in these three sub-areas are converging and discusses how the agent-oriented technologies could provide a good background for developing a unifying approach. Two industrial applications of agent-based systems are described in some detail. The paper also presents both the positive and negative aspects of applying agent-based technologies in industry. [Copyright &y& Elsevier]

Abstract: A model-based autotuning method consists of an identification and a regulator tuning phase. To achieve satisfactory performance and robustness, it is advisable that both phases be tailored a priori to the characteristics of the observed process dynamics. Such characteristics include, but are not limited to, the model structure. For example, overdamped and underdamped models with the same pole-zero structure are parametrised and controlled in different ways. Step response data, that are typically used for the identification phase in the autotuning context, can also be pre-processed to reveal those characteristics. This paper presents a step response classification method suitable for the above purpose. The method is based on a polygonal curve approximation technique for data pre-processing, followed by a neural network classifier. Only normalised I/O data are employed, so that the neural network can be trained off-line with simulated data. Simulation results are reported to show the effectiveness of the proposed classification method in terms of the achievable tuning results. [Copyright &y& Elsevier]

Distributed intelligent control involves matching the control model more closely with the physical system. This is particularly relevant to industrial control systems that are required to control widely distributed devices in an environment that is prone to disruptions. Although considerable work has been conducted on the application of agent technology to the upper levels of manufacturing control (e.g., scheduling, planning, supply chain management, enterprise integration), the application of these techniques to the physical level of control where real-time constraints are prevalent is relatively new. This paper provides background on the work in this area, discusses key research themes in developing real-time distributed intelligent control systems for industrial applications, and concludes by sharing thoughts about the future prospects in this area. [ABSTRACT FROM PUBLISHER]

Abstract: The paper illustrates the benefits of nonlinear model predictive control (NMPC) for the setpoint tracking control of an industrial batch polymerization reactor. Real-time feasibility of the on-line optimization problem from the NMPC is achieved using an efficient multiple shooting algorithm. A real-time formulation of the NMPC that takes computational delay into account is described. The control relevant model for the NMPC is derived from the complex-first principles model and is fitted to the experimental data using maximum likelihood estimation. A parameter adaptive extended Kalman filter (PAEKF) is used for state estimation and on-line model adaptation. The performance of the NMPC implementation is assessed via simulation and experimental results. [Copyright &y& Elsevier]

A planar patch antenna array has been made for radar interferometry. The antenna array consists of 32 rectangular patches on a ceramic loaded teflon substrate. The patches are individually coupled to the microwave electronics in two orthogonal circular polarizations. The radar interferometer is intended for topographic imaging in industrial environment, in this case, a blast furnace producing hot metal for the steel and metal industry. Ordinary imaging techniques with IR or visible radiation are not possible to use due to high temperatures, scattering from dust and particles. A model of blast furnace burden material surface was measured and detected. [ABSTRACT FROM PUBLISHER]

Wireless LAN for Industrial Control (IC-WLAN) provides many benefits, such as mobility, low deployment cost, and ease of reconfiguration. However, the top concern is robustness of wireless communications. Wireless control loops must be maintained under persistent adverse channel conditions, such as noise, large-scale path loss, fading, and many electromagnetic interference sources in industrial environments. The conventional IEEE 802.11 WLANs, originally designed for high bandwidth instead of high robustness, are therefore inappropriate for IC-WLAN. A solution lies in the Direct Sequence Spread Spectrum (DSSS) technology: By deploying the largest possible processing gain (slowest bit rate) that fully exploits the low data rate feature of industrial control, much higher robustness can be achieved. We hereby propose using DSSS-CDMA to build IC-WLAN. We carry out fine-grained physical layer simulations and Monte Carlo comparisons. The results show that DSSS-CDMA IC-WLAN provides much higher robustness than IEEE 802.11/802.15.4 WLAN, so that reliable wireless industrial control loops become feasible. We also show that deploying larger processing gain is preferable to deploying more intensive convolutional coding. The DSSS-CDMA IC-WLAN scheme also opens up a new problem space for interdisciplinary study, involving real-time scheduling, resource management, communication, networking, and control. [ABSTRACT FROM AUTHOR]

A wireless smart sensor platform (based on patent pending technologies, Ramamurthy ) targeted for instrumentation and predictive maintenance systems is presented. The generic smart sensor platform with "plug-and-play" capability supports hardware interface, payload and communications needs of multiple inertial and position sensors, and actuators, using a RF link (Wi-Fi, Bluetooth, or RFID) for communications, in a point-to-point topology. The design also provides means to update operating and monitoring parameters as well as sensor/RF link specific firmware modules "over-the-air." Sample implementations for industrial applications and system performance are discussed [ABSTRACT FROM PUBLISHER]

Active magnetic bearings (AMBs) offer contact-free and frictionless support of rotating machinery. However, because of their limited force capacity, they have to incorporate retainer bearings to protect the rotor and stator laminations against high-amplitude vibration levels. Efficient modeling of contact dynamics is important for the design of adaptive controllers to prevent contact. If, however, contact does occur, it is necessary to recover the rotor position with minimum damage and without shutting down the system. This paper utilizes constrained Lagrangian equations of motion to develop a computationally efficient method to model contact dynamics. The method does not require a direct physical modeling of contact forces, although the contact forces are automatically evaluated from the constraint conditions, and it can be applied to multicontact cases. Furthermore, the technique is capable of detecting and simulating the destructive backward whirl rolling motion. A model reduction technique is introduced to improve the computational efficiency. This is demonstrated by comparing numerical predictions with experimental results, obtained for a 2-m-long flexible rotor supported by two magnetic bearings [ABSTRACT FROM PUBLISHER]

The article discusses the all-coefficient adaptive control method based on a characteristic model. The method consists of three parts, namely all-coefficient adaptive control, golden-section adaptive control, and characteristic modeling. It is simple to use and able to generate highly robust systems. At present, it has been applied to more than 400 systems of nine kinds of engineering plants.

Type-1 fuzzy logic controllers (FLCs) have been applied to date with great success to many different applications. However, for dynamic unstructured environments and many real-world applications, there is a need to cope with large amounts of uncertainties. The traditional type-1 FLC using crisp type-1 fuzzy sets cannot directly handle such uncertainties. A type-2 FLC using type-2 fuzzy sets can handle such uncertainties to produce a better performance. Hence, type-2 FLCs will have the potential to overcome the limitations of type-1 FLCs and produce a new generation of fuzzy controllers with improved performance for many applications, which require handling high levels of uncertainty. This paper introduces briefly the interval type-2 FLC and its benefits. We also present briefly the type-2 FLC application to three challenging domains: industrial control, mobile robots control and ambient intelligent environments control [ABSTRACT FROM PUBLISHER]

The current μ-synthesis tools are not directly suitable for industrial turbine fuel and water control because they lead to high-order controllers with physically meaningless states. The production valve example here is the Woodward GS6 Turbine Gas Metering Valve that has a single-phase permanent magnet motor coupled by a shaft to an inertia disc and a gas metering shoe with a high level of dry (nonlinear) friction and flow forces. The embedded TI-DSP-2407 processor that runs the position controller in the 1 ms loop rate practically limits the maximum controller order to seven. This paper describes how an industrial seventh-order 2-degrees of freedom (DOF) controller was designed by indirectly using the standard tools available in the μ-Toolbox. Step, limit cycle, and frequency response measurements show that the new design compares favorably well with the standard production controller. However, the key advantages were that the first design downloaded into the controller did not require retuning, the design process was higher level, and the measure of ‘robustness’ was in terms of the physical description of plant uncertainties. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents an innovative self-tuning nonlinear controller ASPECT (advanced control algorithms for programmable logic controllers). It is intended for the control of highly nonlinear processes whose properties change radically over its range of operation, and includes three advanced control algorithms. It is designed using the concepts of agent-based systems, applied with the aim of automating some of the configuration tasks. The process is represented by a set of low-order local linear models whose parameters are identified using an online learning procedure. This procedure combines model identification with pre- and post-identification steps to provide reliable operation. The controller monitors and evaluates the control performance of the closed-loop system. The controller was implemented on a programmable logic controller (PLC). The performance is illustrated on a field test application for control of pressure on a hydraulic valve. [Copyright &y& Elsevier]

The IEC 61346 standard describes a reference designation system for identifying the objects and structuring the information of virtually any kind of technical system. The generality of the standard leads in some cases to a slightly loose definition of its concepts, which can hamper its applicability to a concrete domain. Our aim is to make the IEC 61346 standard suitable for the construction of reference designations of industrial plants. Therefore, we impose some constraints to the standard and define the process to follow in order to apply it to industrial automation applications. The removal of ambiguities should also facilitate the interoperability of computer implementations of the standard coming from different vendors. Finally, we show as well how to combine IEC 61346 to existing standards on enterprise-control system integration [ABSTRACT FROM PUBLISHER]

This paper discusses a device that detects bubbles in glue depositions on a windshield glass, which may cause water leakages inside the cockpit. This device is inexpensive, more reliable than other existing solutions, and implements a specific signal treatment and a bubble size calculation model. The device is based on microwave radiation system in the X-band and has been developed and implemented in real production in the final assembly area of the automotive industry [ABSTRACT FROM PUBLISHER]

Including a learning mechanism in SMMAC (switched, multiple-model adaptive control) avoids the need for a priori knowledge of the model set of the plant to control and leads to a significant performance improvement with respect to the sole inclusion of an adaptive control channel in combination with switched fixed local controllers. [ABSTRACT FROM PUBLISHER]

This paper demonstrates the autocovariance least-squares (ALS) technique on two chemical reactor control problems. The method uses closed-loop process data to recover the covariances of the disturbances entering the process, which are required for state estimation. The data used for this purpose may be collected with or without the controllers running. We do not assume that the plant is at steady state nor that only nonzero disturbances are affecting the plant at the time of data collection. The ALS method also accounts for integrated white noise disturbances, which are required for offset-free control. Two examples are provided in this paper: a carefully controlled laboratory reactor and an industrial reactor controlled by a state-of-the-art advanced model predictive control (MPC) system. A variety of control scenarios are tested and the results demonstrate that the ALS method has the potential to improve the best industrial practice of process control by a factor of three to five. [ABSTRACT FROM AUTHOR]

Directory assistance services play an important role in the establishment of telephone calls, particularly business calls, today and will play an even more important role in the future. The majority of these services is provided by specialized call centers, namely DA call centers. Due to severe availability requirements and often due to very specific wishes on the part of the call center operators, the coordination of such a system is complex. This paper describes a new approach to synthesize coordination controllers using formal methods introduced by Ramadge and Wonham. The goal is on the one hand to significantly reduce the development effort, and further-through the exclusion of many potential error sources-to improve the quality and availability of the systems. The results achieved using this new approach are discussed on the basis of a prototypic implementation. [ABSTRACT FROM AUTHOR]

Ethernet was not originally developed to meet the requirements of real-time industrial automation systems and it was commonly considered unsuited for applications at the field level. Hence, several techniques were developed to make this protocol exhibit real-time behavior, some of them requiring specialized hardware, others providing soft-real-time guarantees only, or others achieving hard real-time guarantees with different levels of bandwidth efficiency. More recently, there has been an effort to support quality-of-service (QoS) negotiation and enforcement but there is not yet an Ethernet-based data link protocol capable of providing dynamic QoS management to further exploit the variable requirements of dynamic applications. This paper presents the FTT-Ethernet protocol, which efficiently supports hard-real-time operation in a flexible way, seamlessly over shared or switched Ethernet. The FTT-Ethernet protocol employs an efficient master/multislave transmission control technique and combines online scheduling with online admission control, to guarantee continued real-time operation under dynamic communication requirements, together with data structures and mechanisms that are tailored to support dynamic QoS management. The paper includes a sample application, aiming at the management of video streams, which highlights the protocol's ability to support dynamic QoS management with real-time guarantees. [ABSTRACT FROM PUBLISHER]

Abstract: For a petrochemical distillation column, which separates chemical petrol, a multivariable predictive controller has been developed, simulated and implemented. Feed-forward disturbance control was designed for the compensation of the feed flow fluctuations. The weighting coefficients of the cost function were optimised interactively during simulations. With predictive control not only the operation of the column but also the behaviour of the coupled furnace heating the columns became smoother. Simultaneously, the pressure was minimised which resulted in reduced duty (heating power) consumption. [Copyright &y& Elsevier]

Large portions of a winder's control system software are tested during commissioning. This is inefficient because production is stopped and financial pressures limit the time available for testing. However, it avoids the cost of integrating the winder and electrical drive system before installation. This paper describes a winder simulator that allowed control system software to be tested before installation. Shipping roll build up, parent roll build down, mechanical brakes, and a two-drum windup model were developed. These models were used to simulate the winder, web, and drive system dynamics in real time with a dedicated programmable logic controller (PLC). This PLC provided signals for the winder PLC that would normally be supplied by the drive system and various sensors. The simulator was verified with data from a previously installed winder. The use of the simulator before installation of a new winder demonstrated the benefits of pre-installation software testing. [ABSTRACT FROM AUTHOR]

This paper presents an autotuning process controller aimed at providing efficient rejection of load disturbances in a class of situations that are quite typical in process control, and not easy to treat with most standard autotuning controllers, especially when not only the duration of the load disturbance response, but also the peak deviation of the controlled variable is an issue. The regulator structure is not fixed a priori; this is a peculiarity with respect to the main research stream on autotuning regulators, that refers essentially to fixed-structure (PID) regulators. Both simulation and laboratory examples are reported, to show the advantages of the proposed autotuning controller. [Copyright &y& Elsevier]

This paper considers trajectory planning with given design constraints and design of a feedforward controller for single-axis motion control. A motivation is given for using fourth-order feedforward with fourth-order trajectories. An algorithm is given for calculating higher-order trajectories with bounds on all considered derivatives for point-to-point moves. It is shown that these trajectories are time-optimal in the most relevant cases. All required equations for fourth-order trajectory planning are derived. Implementation, discretization and quantization effects are considered. Simulations and hardware-in-the-loop experiments show superior effectiveness of fourth-order feedforward in comparison with lower-order feedforward. [Copyright &y& Elsevier]