P. Reguera

Visual dynamic model based on self-organizing maps for supervision and fault detection in industrial processes

Visual data mining techniques have experienced a growing interest for processing and interpretation of the large amounts of multidimensional data available in current industrial processes. One of the approaches to visualize data is based on self-organizing maps (SOM), which define a projection of the input space onto a 2D or 3D space that can be used to obtain visual representations. Although these techniques have been usually applied to visualize static relations among the process variables, they have proven to be very useful to display dynamic features of the processes. In this work, an approach based on the SOM to model the dynamics of multivariable processes is presented. The proposed method identifies the process conditions (clusters) and the probabilities of transition among them, using the trajectory followed by the input data on the 2D visualization space. Furthermore, a new method of residual computation for fault detection and identification that uses the dynamic information provided by the model of transitions is proposed. The proposed method for modeling and fault identification has been applied to supervise a real industrial plant and the results are included.

Internet-based remote supervision of industrial processes using self-organizing maps

In upcoming years, the strategies for maintenance, traceability, management and operation of productive processes will demand the use of novel information and communication technologies. Supervisory systems in these new scenarios will have to be able to integrate large volumes of information and knowledge coming both from local and remote points of large processes. These systems will therefore require new tools for management and integration of information and knowledge. In this work, the authors present an internet-based remote supervision system of industrial processes that incorporates powerful data and knowledge visualization tools based on selforganizing maps (SOM). This architecture adds an intermediate layer (database) to the well-known client and server layers, that isolates the client part from the industrial process, allowing to incorporate the required data management and neural network processing tasks. Remote users have access to advanced information visualization tools based on SOM, including both static visualizations, such as component planes or distance maps, and dynamical ones, such as residuals and state trajectory, allowing the interpretation of knowledge extracted by the SOM as well as the analysis and detection of possible abnormal conditions. This architecture has been validated through the supervision of an industrial pilot plant. r 2006 Elsevier Ltd. All rights reserved.

Entornos de experimentación para la Enseñanza de Conceptos Básicos de Modelado y Control

This work presents two experimentation environments as part of educational project called AutomatL@bs. A brief description of both environment is given remarking the advantages on interactivity, virtual and remote labs, and web-based collaborative environments. Furthermore, the main teaching activities and tasks to perform with these environments are presented to be used in basic courses on modelling and control. Finally, some experiences, which have been done using these two environments, are analyzed and discussed.

Inter-University Network of Remote Laboratories

Abstract New technologies provide means and tools to develop new ways of communication, organization, work, etc. that have an impact on all the scopes of the society. Higher education has also experienced those changes. In the last years, the Internet has made possible to explore new teaching strategies. In this paper, the development of a Inter-University Network (IUN) of remote laboratories is proposed. The purpose of this network is training in automatic control using the Internet to work remotely with industrial equipment. This network is supported by a technological platform developed by the research group in Automatic Control at the University of Leon.

Visualization of dynamic parameters of a multivariable system using Self-Organizing Maps. ⋆

Self-organizing maps are excellent tools for information visualization. In this paper, they are used to extract information about the dynamic behavior of a multivariable system in several operating points. The input space of the SOM is constituted by extended vectors composed of the state of the process and the coefficients of the transfer functions that represent the dynamic behavior of the system for each operating point. New tools of visualization, such as maps of multivariable zeros or maps of relative gain, have been defined in order to explore the system so that suitable control strategies can be selected. The proposed method has been tested on a real multivariable system (a Quadruple-tank industrial scale model).

Remote Laboratory for Learning of AC Drive Control

Abstract In this paper, we present the incorporation of a new real industrial system to the Remote Laboratory of Automatic Control of the University of Leon (LRA-ULE). This system consists of an AC motor, a variable frequency drive and a PLC that performs two functions: to control the system and facilitate remote communication. A set of didactic contents and a user interface have also been developed to enable remote interaction with the system. A Drupal-based Content Management System that resides in the technological platform of the LRA-ULE has been used for the operation of the system by the students.

REMOTE OPERATION OF ABB IRB 1400 S4 ROBOT OVER THE INTERNET

Abstract Remote laboratories need physical systems with TCP/IP NICs (Network Interface Cards) to connect them to the Internet. This paper shows a simple way to connect a ABB IRB 1400 S4 Robot to the Internet. This robot has not TCP/IP NIC, it only has a Serial Port. The idea is to configure SLIP (Serial Line Interface Protocol) over a null modem cable.

Active learning in control education

The continuing development of the Information and Communication Technologies (ICT) is bringing about deep changes in the way we work and live, as the widespread application of ICT is accompanied by organizational, commercial, social and legal innovations. These changes have made new tools available for education and training. In particular, Internet Based Education has been growing continuously and several teaching applications make remote connections to physical systems over the net. This paper illustrates how undergraduate students have implemented a remote motor position control. Some of the teaching and learning benefits of such an experience are also identified.

Application of SOM-based visualization maps for time-response analysis of industrial processes

Self-organizing maps have been extensively used for visualization of industrial processes. Nevertheless, most of these approaches lack insight about the dynamic behavior. Recently, an approach to define visualizable maps of dynamics from data has been proposed. We propose the application of this approach to single-input single-output processes by defining several maps related to relevant features in the time-response analysis. This features are commonly used in control engineering. We show that these maps are intuitive and consistent tools for knowledge discovery and validation. They also provide a general overview of the process behavior and can be used along with other previously defined maps for process analysis and monitoring

The virtual laboratory on cybernetics illustrates main results of the paper. Development of an educational tool in LabVIEW and its integration in remote laboratory of automatic control

Abstract The increase of educational activities in automatic control, based on the use of virtual and remote laboratories, is already a fact. For that reason, it is necessary to include and update educational contents in agreement with the technological reality. This implies the development of methods to integrate new educational tools in the aforementioned laboratories in an easy, secure and flexible way. This paper shows how to integrate an educational tool developed in LabVIEW, widely used software, into the structure of our remote laboratory (LRA-ULE). The educational tool provides students with a control problem on a physical system where they need to design a PID regulator. They can also simulate its closed-loop behavior and identify the system in order to compare it with the theoretical model.