Filipe Moutinho

From IOPT Petri nets to C: An automatic code generator tool

This paper presents a tool for automatic generation of ANSI C code from models expressed in IOPT (Input-Output Place-Transition) Petri Nets. The inputs of the tool are PNML (Petri Nets Mark-up Language) files containing the IOPT Petri net models. The tool has two different interfaces: one relying on a simple graphical interface (amenable to be used by humans), and a second one with a command line interface (amenable to be used by humans as well as by other computational systems supporting tools interaction). The tool also allows the user to tune some parts of the automatically generated code considering some characteristics of the implementation platform improving the performance of the generated code. Generated code can be directly deployed into specific controllers; PIC low-cost microcontrollers as well as general purpose PCs have been used for validation.

Asynchronous-Channels Within Petri Net-Based GALS Distributed Embedded Systems Modeling

Model-based development approaches can provide a major contribution in the development of globally asynchronous locally synchronous distributed embedded systems (GALS-DES) if supported by suited modeling formalisms and design automation tools. The use of Petri nets (either low-level or high-level classes) extended with asynchronous-channels (ACs), time domains, priorities, inputs, and outputs is proposed in this paper to model GALS-DES (composed by deterministic components), ensuring that the created GALS model is locally deterministic, distributable, network-independent, and platform-independent. The proposed ACs, with high level of abstraction, specify the components interaction through Petri net objects with specific attributes that unambiguously identify this interaction within the GALS model. Two algorithms are proposed to translate and decompose the GALS model into Petri net models without ACs, which can be used as inputs in model-checking tools and automatic code generators supporting GALS-DES verification and implementation. The specification of a small goods lift distributed controller illustrates the use of the proposed ACs.

Model-checking framework for embedded systems controllers development using IOPT Petri nets

This paper presents a new model-checking framework for embedded systems controllers development using IOPT Petri nets. The new tools, comprehending a state-space generator, a query system and a new automatic code generator, were added to an existing tool framework which already had tools to import and edit controller models, automatic code generators and automatic hardware synthesis tools. The new tools permit the automatic analysis of system properties and the fast detection of errors during early design stages, considerably reducing debug and validation time. All tools share the same Web based user interface, publicly available on the research group Web page (http://gres.uninova.pt).

IOPT-tools — A Web based tool framework for embedded systems controller development using Petri nets

The IOPT-tools Web based tool framework supports the implementation of embedded systems controllers using web-based graphical tools, starting with a graphical editor to specify controllers behavior through associated Petri-net model, complemented with model-checking and system verification tools used to debug and automatically check controller behavior correctness (helping in the detection of model flaws during the early design stages), leading to the final controller implementation code amenable to be deployed into specific platforms and using automatic code generation tools creating C code for software solutions or VHDL code for hardware descriptions.

Asynchronous-Channels and Time-Domains Extending Petri Nets for GALS Systems

A specific class of Petri nets was extended with Asynchronous-Channels (ACs) and Time-Domains (TDs) to support Globally-Asynchronous Locally-Synchronous (GALS) systems’ modeling, analysis and implementation. This non-autonomous class of Petri nets is targeted to support the development of automation and embedded systems using a model-based development approach. It benefits from a tool chain framework previously developed, covering the whole development flow, from specification to hardware and software deployment. With the extended Petri net class is possible to model GALS systems, and use the specification to generate the corresponding state space supporting the behavior verification and providing valuable information for implementation.

Web based IOPT Petri net Editor with an extensible plugin architecture to support generic net operations

This paper presents a new Web based Petri net Editor employing AJAX principles to allow the interactive design and edition of Petri net models using standard Web browsers. The editor includes an integrated plug-in architecture to simplify the addition of generic net operations without requiring the manipulation of internal editor data-structures. IOPT-nets are a non-autonomous Petri net class targeting the model-based development of embedded system controllers and combine the well know properties of Petri nets with input and output signals and events to establish the communication of controllers with the external world. The editor is a part of the IOPT-tools Web service that also contains model-checking and automatic code-generation tools, supporting a complete model-based development work-flow, starting from model design to the final controller code generation. All tools are available at the research group Web page (http://gres.uninova.pt).

IOPT-tools — Towards cloud design automation of digital controllers with Petri nets

This paper describes the IOPT-Tools cloud-based tool-chain, offering a complete set of Petri net tools with a Web interface supporting digital controllers development. The tools include an interactive graphical Petri net editor, a model-checking subsystem composed of a state-space generator, state-space visualization and a query system, and automatic code generation tools that produce software “C” code or VHDL hardware descriptions ready to be deployed into implementation platforms. All interactive tools are executed directly in the users Web Browser using AJAX principles, but file-storage and intensive processing operations are processed in the cloud. For example, state-space computation and the storage of the resulting data is performed in dedicated fast servers, minimizing network traffic and enabling the use of lightweight terminal equipment to access the tools, as simple as smart-phones or tablet computers. The tools are available on-line at http://gres.uninova.pt.

An Ecore based Petri net type definition for PNML IOPT models

In this paper we present a new Input-Output Place-Transition (IOPT) Petri net metamodel and its Petri Net Type Definition (PNTD) using a RELAX NG grammar. This new version introduces changes to the previous metamodel to ensure that the model representation follows the International Standard guidelines to extend PNML and to fully support automatic generation of models state space. The validation of this revised metamodel and the corresponding PNTD were made through case studies. The new concepts introduced in the metamodel have demonstrated their validity and usefulness, in the automatic generation of executable code and the state space. The correctness of the RELAX NG grammar was also validated through case studies.

Ecore representation for extending PNML for Input-Output Place-Transition nets

This paper presents a metamodel for the Input-Output Place-Transition nets (IOPT nets), a Petri net class targeted at controllers modeling. The proposed metamodel reuses many of the elements of the Petri Net Markup Language (PNML) metamodel, such as places, transitions, and arcs; it extends the PNML metamodel for Place/Transition nets to comprise concepts inherent to IOPT nets. The IOPT nets metamodel is described in Ecore format, putting IOPT nets in the puzzle of MDA artifacts taking benefit from the MDA infrastructure.

Extending input-output place-transition Petri nets for distributed controller systems development

Petri nets have been widely used in the design of embedded controllers, namely in electronic hardware and computing platforms design, as well as within automation application areas. This paper presents updated characteristics of one class of Petri nets, named Input-Output Place-Transition Petri nets (IOPT nets), extended to support networked embedded controllers design and globally-asynchronous locally-synchronous (GALS) systems modeling, together with its associated metamodel and execution semantics. The proposed meta-model is compliant with the Petri Net Markup Language (PNML) metamodel, augmented with the descriptions for inputs and outputs, as well as for time domains and communication channels. The meta-model is described using UML class diagrams and has an equivalent Ecore meta-model that positioning IOPT nets within the Eclipse Modeling Framework (EMF).