Maintainability and evolvability of control software in machine and plant manufacturing -- An industrial survey

Automated Production Systems (aPS) have lifetimes of up to 30-50 years, throughout which the desired products change ever more frequently. This requires flexible, reusable control software that can be easily maintained and evolved. To evaluate selected criteria that are especially relevant for maturity in software maintainability and evolvability of aPS, the approach SWMAT4aPS+ builds on a questionnaire with 52 questions. The three main research questions cover updates of software modules and success factors for both cross-disciplinary development as well as reusable models. This paper presents the evaluation results of 68 companies from machine and plant manufacturing (MPM). Companies providing automation devices and/or engineering tools will be able to identify challenges their customers in MPM face. Validity is ensured through feedback of the participating companies and an analysis of the statistical unambiguousness of the results. From a software or systems engineering point of view, almost all criteria are fulfilled below expectations

Design of a Control System for a Reconfigurable Engine Assembly Line

Today’s automotive manufacturing environment is dynamic. It is characterized by short life cycles of products especially in powertrain, due in part to changing Government regulations for fuel economy. In the USA, the National Highway Traffic and Safety Administration (NHTSA), Corporate Average Fuel Economy (CAFE) mandates an average of 29 miles per gallon (mpg), gradually increasing to 35.5 mpg by 2016 and 54.5 mpg towards 2025. Life cycles of engines and transmissions have consequently shortened, driving automakers to develop and manufacture more efficient powertrains. Not long ago, plants produced engines for decades, with minor modifications warranting slight manufacturing line rework. Conversely, today’s changing trends require machines and complete engine line overhauls rendering initial setups obsolete. Automakers compete to satisfy government regulations for best mileage and also lower manufacturing cost, thus the adoption of Reconfigurable Manufacturing Systems (RMS). Production lines follow modularity in designs, for hardware and software, to adapt to new business conditions, economically and time-wise. Information Technology (IT) and Controls are growing closer with the line of demarcation disappearing in manufacturing. Controls are benefiting from opportunities in IT, hardware and software. The advent of agent-based technology which are autonomous, cooperative and extendible in different production activities, helped to develop controls for RMS in academia. Component-based software suitable for RMS modularity and plug-and-play hardware/software components has gained decades of popularity in the software industry. This thesis implements distributed controls imbedding component-based technology and IEC 61311-3 function block standard for automotive engine assembly, which will contribute to these developments. The control architecture provides reconfigurability which is lacking in current manufacturing systems. The research imbeds: 1- Reconfigurability - Fitting RMS-designed hardware towards new manufacturing, 2- Reusability - Building software library for reuse across assembly lines, and 3- Plug-and-Play - Embedding easy to assemble software components (function blocks)

Bewegungssteuerungen auf Basis des Hybriden Funktionsplanes

Für ereignisgesteuerte Systeme mit mehrdimensionalen Bewegungsabläufen wurde im Fachausschuss 4.12 "Bewegungssteuerungen für Be- und Verarbeitungsmaschinen" der VDI/VDE-Gesellschaft Mess- und Automatisierungstechnik (GMA) die VDI/VDE-Richtlinie 3684 "Beschreibung ereignisgesteuerter Bewegungsabläufe mit Funktionsplänen" als interdisziplinär verständliches und anschauliches Dokumentationsmittel und Entwurfswerkzeug erarbeitet. Mit der Blockbibliothek Funktionsplan auf Grundlage der in der Richtlinie 3684 vorgeschlagenen Systembeschreibung ist ein durchgängiger Entwurfsweg bis zur Überprüfung des Systemverhaltens ereignisgesteuerter Systeme mittels Simulation einschließlich frühzeitiger Erkennung von Fehlern im Entwurfsprozess und Kodegenerierung möglich. Die FUP Blockbibliothek liegt als Erweiterungs-Blockbibliothek für SIMULINK vor und wurde hinsichtlich ihrer wesentlichen Eigenschaften zur Simulation von ereignisgesteuerten Prozessen speziell in mechatronischen Systemen entwickelt. Die Blockikonen gewährleisten schon nach kurzer Einarbeitungszeit einen sicheren Einsatz der Blöcke, damit kann auf Blockkürzel im Sinne der Richtlinie zwecks besserer Übersichtlichkeit verzichtet werden. Zweisprachige Blockhilfen sind in Version 3.1 für alle Blöcke on-line verfügbar. Graphisch programmierte Funktionspläne können mittels Toolbox Funktionsplanprüfung vorzugsweise über GUI, bei Bedarf auch durch MATLAB Skripte, auf Eingabe- und Programmierfehler geprüft werden. Die Prüfung kann wahlweise vollständig oder auf ausgewählte Fehler erfolgen. Ergebnisausgaben sind entweder in gestraffter Form oder ausführlich einschließlich von Hinweisen möglich. Überprüft werden können Parameter (z.B. Zustands- u. FUP-Nummern, Variablen, Fehlerbehandlung), Syntax (vgl. Richtlinie), Sackgassen (erste/alle) und Rückführschleifen (Entkopplung). Hybride Funktionspläne sind in Echtzeitkode für eine Zielhardware übersetzbar. Voraussetzung ist ein Standard ANSI C Compiler. Die Blockbibliothek Funktionsplan ist eine kostengünstige, richtliniennahe Alternative und ermöglicht eine vom Normalablauf separate, graphisch programmierte Fehlerbehandlung ohne Verlust an Übersichtlichkeit. Die Anwendung der Blöcke wird durch 11 Beispiele veranschaulicht.:1. Einleitung 2. Ausgangspunkt Arbeitsdiagramm 3. Hybrider Funktionsplan 3.1 Begriffsbestimmung 3.2 Anwendungsbeispiel 3.3 Vom Arbeitsdiagramm zum Hybriden Funktionsplan 4. Steuerungstechnische Umsetzung 4.1 Auswahl einer Basissoftware 4.2 Maschinenkodeerzeugung mit der Basissoftware 5. Projektierung mit FUP 5.1 Eigenschaften der SIMULINK Blockbibliothek FUP 5.2 Projektierungsschritte 6. AusblickThe department committee 4.12 "Motion control of machine tools and processing machines" of the VDI/VDE Society for Measurement and Automatic Control (GMA) has established a manufacturer-neutral guideline No. 3684 for event-driven systems with multi-dimensional motion sequences. This guide-line is entitled "Description of event-driven motion processes by function charts" and constitutes a graphically clear design and documentation tool that is well-suited for interdisciplinary application. The block library Function Chart has been defined based on system descriptions suggested in guideline 3684. This library makes available a uniform design procedure. It covers the documentation, the behaviour test of event-driven systems by means of simulation including the early detection of design process faults, the test of realization variants as well as the code generation. Block library Function Chart is an add-on library for SIMULINK. With regard to its essential features it has been developed for the design, simulation, code generation and the description of event-driven systems especially for mechatronics, mechanical and electrical engineering. The created block icons make it possible to get familiar with add-on library Function Chart within a short period of time whereupon block mnemonics may be hidden in order to get a high graphical clearness and to fulfil the requirements of the guideline. Versions 3.1 bilingual on-line block help is available for all blocks. Graphically programmed function charts may be checked for input and programming errors preferably with help of Toolbox "Function Chart Check" by means of GUI's and if necessary also by MATLAB scripts. The check may be done completely or alternatively for selected errors. Output of result is possible either in detail inclusively eventual hints or in shortened form. A function chart may be checked for parameter errors (e.g. state and FUP numbers, variables, error handling), syntax errors (see guideline), dead ends (first or all) and uncoupled loops (arithmetic loops). Standard ANSI C compiler availability stands for a precondition for real time code generation. The block library Function Chart offers a reasonable alternative and allows separate motion error handling sequences which are separated from normal motion sequences without any loss of a well-ordered graphical arrangement. Currently 11 examples demonstrate the application of the blocks.:1. Einleitung 2. Ausgangspunkt Arbeitsdiagramm 3. Hybrider Funktionsplan 3.1 Begriffsbestimmung 3.2 Anwendungsbeispiel 3.3 Vom Arbeitsdiagramm zum Hybriden Funktionsplan 4. Steuerungstechnische Umsetzung 4.1 Auswahl einer Basissoftware 4.2 Maschinenkodeerzeugung mit der Basissoftware 5. Projektierung mit FUP 5.1 Eigenschaften der SIMULINK Blockbibliothek FUP 5.2 Projektierungsschritte 6. Ausblic

Modelos y plataforma IEC 61499 adaptados al control distribuido de máquinas herramienta en sistemas de fabricación ágil

Los sistemas de fabricación han ido evolucionando para adaptarse a las cada vez más cambiantes demandas del mercado, pasando de los sistemas de fabricación en masa a los sistemas flexibles y, finalmente, a los sistemas ágiles. Estos últimos están soportados por sistemas reconfigurables, capaces de ser modificados sin parar su funcionamiento, así como por tecnologías de la información y la comunicación, por lo que pueden adaptarse muy rápidamente a cambios en la producción. Para denominar estos nuevos sistemas han surgido también términos como e-manufacturing, cloud-manufacturing, industrie 4.0. El estándar actual de referencia para el desarrollo de software de control en los sistemas de fabricación es IEC 61131, del que algunos trabajos han indicado su poca adecuación frente a los requisitos de los nuevos sistemas. Por este motivo ha surgido el más complejo IEC 61499, que define arquitecturas y modelos para un software de control distribuido y reconfigurable. La industria demanda a este estándar la capacidad para desarrollar software de control: predecible, escalable, mantenible y extensible. A este respecto, aunque ha sido objeto de múltiples trabajos por parte de la comunidad académica, a día de hoy IEC 61499 no ha adquirido esa capacidad, por lo que no es aceptado todavía por la industria. El objeto de la presente tesis es aportar propuestas que contribuyan a que el estándar alcance dicha capacidad. Con este fin, se propone el uso de metodologías y modelos de componentes software adaptados al dominio de aplicación, en particular, al control de máquinas herramienta en sistemas de fabricación ágil. Este dominio ha sido elegido por su complejidad, frente a los sencillos tipos de aplicación y casos de uso considerados en anteriores propuestas relacionadas con IEC 61499. Para establecer dichas metodologías y modelos adaptados se estudia en primer lugar el dominio indicado, determinando los principios de diseño de su software de control. Estos principios sirven de base para efectuar una revisión del estado actual del estándar. Seguidamente, se propone y modela el control distribuido de una máquina herramienta genérica, a partir del cual se establecen los modelos de bloque función y de ejecución IEC 61499 adaptados a ese dominio. Dichos modelos facilitan el establecimiento de una metodología de diseño, a la vez que permiten una implementación del estándar determinista, eficiente, escalable y que cumple restricciones de tiempo real. A la hora de verificar experimentalmente la metodología y los modelos adaptados es necesaria una plataforma de ejecución. Debido a que las plataformas IEC 61499 existentes no soportan dichos modelos se ha especificado, diseñado e implementado la plataforma COSME. A diferencia de anteriores plataformas, ésta incorpora características que hacen posible su empleo en entornos industriales. En este sentido, la plataforma COSME ha sido desarrollada dentro de un proyecto de investigación, transferencia y colaboración tecnológica entre la universidad y un grupo industrial fabricante de máquinas herramienta. Dicho proyecto ha permitido que esta plataforma, la metodología y los modelos adaptados hayan sido validados en casos de uso reales

Service-oriented architecture for device lifecycle support in industrial automation

Dissertação para obtenção do Grau de Doutor em Engenharia Electrotécnica e de Computadores Especialidade: Robótica e Manufactura IntegradaThis thesis addresses the device lifecycle support thematic in the scope of service oriented industrial automation domain. This domain is known for its plethora of heterogeneous equipment encompassing distinct functions, form factors, network interfaces, or I/O specifications supported by dissimilar software and hardware platforms. There is then an evident and crescent need to take every device into account and improve the agility performance during setup, control, management, monitoring and diagnosis phases. Service-oriented Architecture (SOA) paradigm is currently a widely endorsed approach for both business and enterprise systems integration. SOA concepts and technology are continuously spreading along the layers of the enterprise organization envisioning a unified interoperability solution. SOA promotes discoverability, loose coupling, abstraction, autonomy and composition of services relying on open web standards – features that can provide an important contribution to the industrial automation domain. The present work seized industrial automation device level requirements, constraints and needs to determine how and where can SOA be employed to solve some of the existent difficulties. Supported by these outcomes, a reference architecture shaped by distributed, adaptive and composable modules is proposed. This architecture will assist and ease the role of systems integrators during reengineering-related interventions throughout system lifecycle. In a converging direction, the present work also proposes a serviceoriented device model to support previous architecture vision and goals by including embedded added-value in terms of service-oriented peer-to-peer discovery and identification, configuration, management, as well as agile customization of device resources. In this context, the implementation and validation work proved not simply the feasibility and fitness of the proposed solution to two distinct test-benches but also its relevance to the expanding domain of SOA applications to support device lifecycle in the industrial automation domain