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Customizable service-oriented Petri net controllers

Publication . Mendes, João M.; Restivo, Francisco; Leitão, Paulo; Colombo, Armando W.

In industrial automation, service-orientation is a relatively new and ascending concept and thus, concrete integrated methodologies are missing to accomplish the required development tasks. A suitable approach is to use the powerful set of features that Petri nets formalism provides for such dynamic systems. This paper presents a token game template that is part of the open methodology for the development of customized Petri nets controllers, targeting the engineering of service-oriented industrial automation. This template is based on a state machine specification for the life-cycle of transitions that leaves several options open for extending it with features depending on the application. The practical use and implementation should bring, among others, featured-full and integrated modeling, analysis and control capabilities, which is required by service-oriented ecosystems. This core structure was used and validated in the development of control applications for an industrial automation system.

2009Conference paper

Open access

Petri net based engineering and software methodology for service-oriented industrial automation

Publication . Mendes, João M.; Restivo, Francisco; Leitão, Paulo; Colombo, Armando W.

Collaborative industrial systems are becoming an emergent paradigm towards flexibility. One promising solution are service-oriented industrial automation systems, but integrated software methodologies and major frameworks for the engineering are still missing. This paper presents na overview of the current results on a unified and integrated methodology based on intrinsic and novel features of Petri nets. These nets are applied to the modeling, analysis, service management, embedded software controllers, decision support system and monitoring, to improve the fundamentals in the engineering of service-oriented automation systems. The solution may contribute to the reduction of the design, operational and reconfiguration phases in the life-cycle of novel automation environments. Results were obtained and discussed from simulations and real industrial demonstrators.

2010Conference paper

Open access

Energy aware knowledge extraction from Petri nets supporting decision-making in service-oriented automation

Publication . Leitão, Paulo; Alves, Joel; Mendes, João M.; Colombo, Armando W.

This paper introduces an approach to decision support systems in service-oriented automation control systems, which considers the knowledge extracted from the Petri nets models used to describe and execute the process behavior. Such solution optimizes the decision-making taking into account multi-criteria, namely productive parameters and also energy parameters. In fact, being manufacturing processes typically energy-intensive, this allows contributing for a clean and saving environment (i.e. a better and efficient use of energy). The preliminary experimental results, using a real laboratorial case study, demonstrate the applicability of the knowledge extracted from the Petri nets models to support real-time decision-making systems in service-oriented automation systems, considering some energy efficiency criteria.

2010Conference paper

Open access

Service-oriented agents for collaborative industrial automation and production systems

Publication . Mendes, João M.; Leitão, Paulo; Restivo, Francisco; Colombo, Armando W.

Service-oriented Multi-Agent Systems (SoMAS) is an approach to combine the fundamental characteristics of service-oriented and multi-agent methods into a new platform for industrial automation. Several research works already targeted the connection of these technologies, presenting different perspectives in how and why to join them. This research focuses on available efforts and solutions in the area of SoMAS and explains the idea behind the service-oriented agents in industrial automation. A SoMAS system is mainly composed by shared resources in form of services and their providing/requesting agents. The paper also discusses the required engineering aspects of these systems, from the internal anatomy to the interaction patterns. Parameters of flexibility, reconfiguration, autonomy and reduced development efforts were considered and they should be the trademark of SoMAS. Aiming to illustrate the proposed approach, an example of service-oriented automation agents is given.

2009Conference paper

Open access

Process optimization of service-oriented automation devices based on Petri nets

Publication . Mendes, João M.; Leitão, Paulo; Restivo, Francisco; Colombo, Armando W.

This paper introduces a novel method for the specification and selection of criteria-weighted operation modes for the orchestration of services in industrial automation using Petri nets. The objective is to provide to the internal decision support system of a service-oriented automation device or of another applicable computational system the capability to select the best path in a Petri net orchestration model considering different criteria to evaluate the quality of services, such as the time, energy efficiency and reliability. The transition-invariants obtained from the Petri net represent the set of possible modi operandi and these are then weighted with decision criteria. The result will be afterwards evaluated in order to select the optimal modus operandi to be executed by the device. Based on the experiments, this method permits the dynamic optimization of processes in real-time, considering available parameters from devices and other resources.

2010Conference paper

Open access