Minimalist Architecture to Generate Embedded System Web User Interfaces

Part 9: Embedded Systems and Petri NetsInternational audienceThis paper presents a new architecture to semi-automatically generate Web user interfaces for Embedded Systems designed using IOPT Petri Net models. The user interfaces can be used to remotely control, monitor and debug embedded systems using a standard Web Browser. The proposed architecture takes advantage of the distributed nature of the Internet to store all static user interface data and software on third-party Web services (the Cloud), and execute the user-interface code on the user’s Web Browser. A simplified protocol is proposed to enable remote control, status-monitoring, debugging and step-by-step execution, minimizing resource consumption on the physical embedded devices, including processing load, memory and communication bandwidth. As the user interface data and code are kept on third-party Web services, these resources can be shared among multiple embedded device units, and the hardware requirements to implement the devices can be simplified, leading to reduced cost solutions. To prevent down-time due to network problems or server failures, a fault-tolerant topology is suggested. The distributed architecture is transparent to end-users, observing just a Web interface for an embedded device on the other side of an Internet URL

The DS-Pnet modeling formalism for cyber-physical system development

This work presents the DS-Pnet modeling formalism (Dataflow, Signals and Petri nets), designed for the development of cyber-physical systems, combining the characteristics of Petri nets and dataflows to support the modeling of mixed systems containing both reactive parts and data processing operations. Inheriting the features of the parent IOPT Petri net class, including an external interface composed of input and output signals and events, the addition of dataflow operations brings enhanced modeling capabilities to specify mathematical data transformations and graphically express the dependencies between signals. Data-centric systems, that do not require reactive controllers, are designed using pure dataflow models. Component based model composition enables reusing existing components, create libraries of previously tested components and hierarchically decompose complex systems into smaller sub-systems. A precise execution semantics was defined, considering the relationship between dataflow and Petri net nodes, providing an abstraction to define the interface between reactive controllers and input and output signals, including analog sensors and actuators. The new formalism is supported by the IOPT-Flow Web based tool framework, offering tools to design and edit models, simulate model execution on the Web browser, plus model-checking and software/hardware automatic code generation tools to implement controllers running on embedded devices (C,VHDL and JavaScript). A new communication protocol was created to permit the automatic implementation of distributed cyber-physical systems composed of networks of remote components communicating over the Internet. The editor tool connects directly to remote embedded devices running DS-Pnet models and may import remote components into new models, contributing to simplify the creation of distributed cyber-physical applications, where the communication between distributed components is specified just by drawing arcs. Several application examples were designed to validate the proposed formalism and the associated framework, ranging from hardware solutions, industrial applications to distributed software applications

Integrating the MVC paradigm into an object-oriented framework to accelerate GUI application development

Applications supporting a graphical user interface (GUI) are difficult to write. While existing tools can accelerate software development, they suffer from a number of problems that limit their helpfulness. They offer too little functionality, and support only a small part of the GUI software development task. They lack architectural models and abstraction mechanisms to support large GUI applications. Their user interface specifications are difficult to understand. edit, and reuse. They lack a single conceptual, graphical model to be used as a medium for integrating specification, documentation, design, simulation, validation, and rapid prototyping. We present an approach that solves many of these problems with existing systems by supporting a larger part of the development task, providing a unifying conceptual graphical model, and providing tools for graphical specification and manipulation of oar underlying architectural model. Our approach uses the MVC paradigm, an application framework, reusable classes, and pluggable and adaptable domain specific views to offer greater functionality and to support a greater part of the development task. Our object-oriented approach encourages the reuse of code. An architectural model for large GUI applications is supported by the reusable design embodied in our framework and by the visual Petri net with net hierarchy (subnets). The use of a visual Petri net also makes user interface and design specifications easier to understand, edit, and reuse. By using an annotated Petri net we are able to provide a single conceptual graphical model that integrates specification, documentation, design. validation, and rapid prototyping. Oregon Speedcode Universe version 3.0 (OSU v3.0) is a second generation experimental object-oriented tool for GUI software development currently under construction at Oregon State University. It consists of an MVC-based application framework, a class library of reusable code, and a set of integrated tools for specification, modeling, simulation, validation, and rapid prototyping of GUI applications. It is written in C++ on the Macintosh and produces C++ code that can be compiled to produce stand-alone applications. This paper presents an overview of the OSU v3.0 approach and focuses on the MVC-based framework as a way of supporting added functionality, greater reuse of code, and a higher level of abstraction to the task of developing GUI applications. My responsibility in this project was implementation of the MVC, application, and window classes. These are detailed in the final section and an example of their use is included

Model-based engineering of animated interactive systems for the interactive television environment

Les interfaces graphiques étaient la plupart du temps statiques, et représentaient une succession d'états logiciels les uns après les autres. Cependant, les transitions animées entre ces états statiques font partie intégrante des interfaces utilisateurs modernes, et leurs processus de design et d'implémentations constituent un défi pour les designers et les développeurs. Cette thèse propose un processus de conception de systèmes interactifs centré sur les animations, ainsi qu'une architecture pour la définition et l'implémentation d'animations au sein des interfaces graphiques. L'architecture met en avant une approche à deux niveaux pour définir une vue haut niveau d'une animation (avec un intérêt particulier pour les objets animés, leurs propriétés à être animé et la composition d'animations) ainsi qu'une vue bas niveau traitant des aspects détaillés des animations tels que les timings et les optimisations. Concernant les spécifications formelles de ces deux niveaux, nous utilisons une approche qui facilite les réseaux de Petri orientés objets pour la conception, l'implémentation et la validation d'interfaces utilisateurs animées en fournissant une description complète et non-ambiguë de l'ensemble de l'interface utilisateur, y compris les animations. Enfin, nous décrivons la mise en pratique du processus présenté, illustré par un cas d'étude d'un prototype haute-fidélité d'une interface utilisateur, pour le domaine de la télévision interactive. Ce processus conduira à une spécification formelle et détaillée du système interactif, et incluera des animations utilisant des réseaux de Petri orientés objet (conçus avec l'outil PetShop CASE).Graphical User Interfaces used to be mostly static, representing one software state after the other. However, animated transitions between these static states are an integral part in modern user interfaces and processes for both their design and implementation remain a challenge for designers and developers. This thesis proposes a process for designing interactive systems focusing on animations, along with an architecture for the definition and implementation of animation in user interfaces. The architecture proposes a two levels approach for defining a high-level view of an animation (focusing on animated objects, their properties to be animated and on the composition of animations) and a low-level one dealing with detailed aspects of animations such as timing and optimization. For the formal specification of these two levels, we are using an approach facilitating object-oriented Petri nets to support the design, implementation and validation of animated user interfaces by providing a complete and unambiguous description of the entire user interface including animations. Finally, we describe the application of the presented process exemplified by a case study for a high-fidelity prototype of a user interface for the interactive Television domain. This process will lead to a detailed formal specification of the interactive system, including animations using object-oriented Petri nets (designed with the PetShop CASE tool)

A new approach to the development and maintenance of industrial sequence logic

This thesis is concerned with sequence logic as found in industrial control systems, with the focus being on process and manufacturing control systems. At its core is the assertion that there is a need for a better approach to the development of industrial sequence logic to satisfy the life-cycle requirements, and that many of the ingredients required to deliver such an approach are now available. The needs are discussed by considering the business case for automation and deficiencies with traditional approaches. A set of requirements is then derived for an integrated development environment to address the business needs throughout the control system life-cycle. The strengths and weaknesses of relevant control system technology and standards are reviewed and their bias towards implementation described. Mathematical models, graphical methods and software tools are then assessed with respect to the requirements for an integrated development environment. A solution to the requirements, called Synect is then introduced. Synect combines a methodology using familiar graphical notations with Petri net modelling supported by a set of software tools. Its key features are justified with reference to the requirements. A set of case studies forms the basis of an evaluation against business needs by comparing the Synect methodology with current approaches. The industrial relevance and exploitation are then briefly described. The thesis ends with a review of the key conclusions along with contributions to knowledge and suggestions for further research

Model and Tools for Integrating IoT into Mixed Reality Environments: Towards a Virtual-Real Seamless Continuum

International audienceThis paper introduces a new software model and new tools for managing indoor smart environments (smart home, smart building , smart factories, etc.) thanks to MR technologies. Our fully-integrated solution is mainly based on a software modelization of connected objects used to manage them independently from their actual nature: these objects can be simulated or real. Based on this model our goal is to create a continuum between a real smart environment and its 3D digital twin in order to simulate and manipulate it. Therefore, two kinds of tools are introduced to leverage this model. First, we introduce two complementary tools, an AR and a VR one, for the creation of the digital twin of a given smart environment. Secondly, we propose 3D interactions and dedicated metaphors for the creation of automation scenarios in the same VR application. These scenarios are then converted to a Petri-net based model that can be edited later by expert users. Adjusting the parameters of our model allows to navigate on the continuum in order to use the digital twin for simulation, deployment and real/virtual synchronization purposes. These different contributions and their benefits are illustrated thanks to the automation configuration of a room in our lab

Component-based control system development for agile manufacturing machine systems

It is now a common sense that manufactures including machine suppliers and system integrators of the 21 st century will need to compete on global marketplaces, which are frequently shifting and fragmenting, with new technologies continuously emerging. Future production machines and manufacturing systems need to offer the "agility" required in providing responsiveness to product changes and the ability to reconfigure. The primary aim for this research is to advance studies in machine control system design, in the context of the European project VIR-ENG - "Integrated Design, Simulation and Distributed Control of Agile Modular Machinery"

Comprehensive support for developing graphical highly interactive user interface systems

The general problem of application development of interactive GUI applications has been addressed by toolkits, libraries, user interface management systems, and more recently domain-specific application frameworks. However, the most sophisticated solution offered by frameworks still lacks a number of features which are addressed by this research: 1) limited functionality -- the framework does little to help the developer implement the application's functionality. 2) weak model of the application -- the framework does not incorporate a strong model of the overall architecture of the application program. 3) representation of control sequences is difficult to understand, edit, and reuse -- higher-level, direct-manipulation tools are needed. We address these problems with a new framework design called Oregon Speedcode Universe version 3.0 (OSU v3.0) which is shown, by demonstration, to overcome the limitations above: 1) functionality is provided by a rich set of built-in functions organized as a class hierarchy, 2) a strong model is provided by OSU v3.0 in the form of a modified MVC paradigm, and a Petri net based sequencing language which together form the architectural structure of all applications produced by OSU v3.0. 3) representation of control sequences is easily constructed within OSU v3.0 using a Petri net editor, and other direct manipulation tools built on top of the framework. In ddition: 1) applications developed in OSU v3.0 are partially portable because the framework can be moved to another platform, and applications are dependent on the class hierarchy of OSU v3.0 rather than the operating system of a particular platform, 2) the functionality of OSU v3.0 is extendable through addition of classes, subclassing, and overriding of existing methods. The main contribution of this research is in the design of an application framework that uses Petri nets as the computational model of data processing in the synthesized application. OSU v3.0 is the first framework to formalize sequencing, and to show that complex GUI applications can indeed be quickly and reliably produced from such a framework