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Abstract Coordination is an important requirement for most Multiagent Systems. A setplay is a particular instance of a coordinated plan for multi-robot systems in collective sports. Setplays are usually designed by robotics specialists using some existing tools, like the SPlanner, or by hand-coding. This work presents recent improvements to the Strategy Planner (SPlanner) and its corresponding FCPortugal Setplays Framework (FSF) to provide sophisticated setplays. This toolkit is useful to design strategic plans for robotic soccer teams as a particular case of Multi-Agent Systems (MASs). The new enhancements enable more realistic setplays, including, but not limited to, the definition of better pass strategies and defensive setplays. The enhanced tool is used to populate a dataset with demonstrations made by soccer experts and used in a Learning from Demonstration (LfD) approach to allow robotic soccer teams to learn new setplays. A new demonstration mode in the RoboCup Soccer Simulation 3D (SSIM3D) viewer RoboViz was also introduced to integrate this tool with SPlanner. Domain experts can use this set of tools to capture a specific scene in a game in RoboViz and use it as an initial step for a new setplay recommendation in SPlanner. The resulting dataset is organized into fuzzy clusters to be used in a reinforcement learning strategy. This paper describes the whole process. Article Highlights This paper’s main contribution is generating a dataset of setplays to support learning from demonstration in robotic soccer. A set of new features were added to the Strategic Planner(SPlanner) to enable the design of more realistic setplays. The official RoboCup viewer (Roboviz) was integrated with SPlanner using a new demonstration mode.

With the advent of the global and digital world, the number of geographically dispersed firms throughout the world has increased and the problem of Supply Chain (SC) disruption appeared as a main c...

Sustainability management at the production control can make business feasible and profitable, ensuring the safety of the employees, communities and consumers, in addition to the efficient use of resources/raw materials. However, industrial standards do not describe how to deal with sustainability at Productive Systems (PSs) design and their control. Therefore, this paper proposes a framework based on extensions of the ANSI/ISA95 standard for assessment of PSs performance considering sustainability indicators. The framework also considers information processing, storage and access remote for each system component through cyber-physical system and cloud computing technologies. Furthermore, a systematic approach based on Petri Nets (PNs) techniques ensures a formalism to verify and validate the behavior of the Sustainable Productive Systems (SuPSs). Application cases demonstrate and indicate the advantages of the proposed framework to the feasibility, profitability, safety and efficiency of SuPSs.

This paper proposes a control architecture for reconfigurable manufacturing systems and its design method based on Petri nets (Input Output Place Transition and Production Flow Schema), Service-Oriented Architecture and Holonic and Multi-Agent System techniques, among other good practices. The control architecture integrates value-added activities, information and resources. The method considers the exchange of knowledge among heterogeneous business workflow of manufacturing subsystems in different geographical locations, and allows modeling process, product, machine and device control. An example demonstrates advantages of the resulting control system.

There is a kind of movement for people to consider sustainability in all their daily activities, not only in the acquisition of goods and services but including the care for health. This induces the emergence of a new business model. Any type of production system (PS) should thus consider sustainability in all its activities and a relationship, which includes not only customers but suppliers, and partners involved from conception, design, manufacturing and provide even service after the use and the disposal of the products. Therefore, an evaluation procedure for PS is proposed to monitor four aspects of sustainability, namely: environmental, social, economical and technological. A framework is considered to deal with the concepts of sustainability and to evaluate performance in industrial PSs considering the indicators to qualify and to quantify their sustainability. It adopts the Petri net technique and extensions of the ANSI/ISA95; Cyber Physical System (CPS) and Smart Grid resources are also considered to treat information processing, storage and access flows by each system component and a Cloud Computing System to connect dispersed PSs. In addition, an evaluation process is systematized to support sustainable PSs by the rational use of production resources and the environment, to guarantee the safety of employees and to maintain the economic profitability of the company, thus, making production processes more efficient.

In a new industrial business model, all aspects of sustainability, i.e. (i) environmental for reduction of negative impacts of using resources, (ii) economic for viability and profitability of business, (iii) social for assuring the safety of employees, communities and consumers, and (iv) technological for efficient and safe use of production resources, need to be effectively incorporated in the productive activities. On the other hand, existing decision-making structures in industries do not explicitly consider how to deal with sustainability indicators when developing a productive system (PS) and its control system. Therefore, this paper discusses the components of a framework and their interactions to apply new concepts to evaluate performance in industrial PSs considering the indicators to qualify and to quantify their sustainability. The framework adopts the Petri net technique and extensions of the ANSI/ISA 95 standard to systemize the evaluation process. This approach assures a formal way to verify and to validate the system sustainability. Besides, the framework considers information processing, storage and access flows between each system component under Cyber Physical System (CPS) and Cloud Computing concepts.

Safety is an important issue that has increasingly been focused on. The reasons are the numerous accidents in process industries which require a hard look at current practices such as process design, process control, risk analysis and control, and risk assessment. Critical faults in process industries could lead to loss of lives, environmental damage and significant financial losses of property and equipment. Accidents typically result from the absence or breach of defenses or breach of security restrictions. The so-called defense-in-depth principle embodies the idea of multiple lines of defense and safety barriers along the accident scene; and this principle avoids ensuring the dependence of safety on a single element. Additionally, for several accidents, the identification of concealed faults and/or non observability of critical faults have been reported, during the evolution of faults following the accident, as relevant factors in the occurrence of catastrophic accidents. Finally, as process industries, are complex systems that interact with the environment, the disturbances caused by the environment must be properly diagnosed and treated by these systems. Based on these issues, this work initially proposes a safety control architecture that integrates the concept of reactivity associated with de principles of defense-in-depth, and safety-diagnosability addressing aspects related to critical faults prevention, mitigation and description of the development of failures. We believe that the safety control architecture is a change in paradigm contributing to risk analysis, risk and hazard control, and risk assessment.

This paper presents a method to design a reconfigurable distributed manufacturing control systems which integrates heterogeneous technologies of facilities that are geographically distributed. Due to the heterogeneity of the environment, the method explores concepts of different techniques and takes the best practices from each one. Mechanisms for reconfiguration are proposed using holonic and multi-agent systems techniques. The service-oriented architecture concept is applied to define the interfaces for communication. A combined top-down and bottom- up approach is described using Petri net models. An application example demonstrates the characteristics and advantages of the proposed method, such as autonomy, reactivity, reuse models, interoperability and reconfiguration flexibility.

Productive systems (PS) should currently consider the efficient use of resources (such as technological transformation, handling and material transport) besides the dispersed distribution of productive plants and sustainability concepts to allow the adequate use of environmental resources and reduce costs through local facilities. However, in the literature there are not widely accepted criteria to evaluate this class of Sustainable and Dispersed Productive Systems (SDPS). Therefore, this work introduces a framework for SDPS performance evaluation by extending the system requirements in the ANSI/ISA-95 standard specifications. Petri net (PN) technique and its extension, Production Flow Schema (PFS), are used to systematize the collection of production data and indexes to evaluating the SDPS performance. Cloud computing technology is also considered to provide resources to access information from SDPS. The presented method allows obtaining and choosing the better indicator for sustainable SDPS.

With the advent of globalization, mitigating supply chain disruptions is the differential for any company. However, mitigating supply chain disruption-related risks in companies is a difficult task. There are some ISO norms that provide standards that can make systems to deal with supply chain disruptions and there are some modeling techniques that ensure that supply chain disruptions be mitigated. Although both approaches do not eliminate supply chain disruptions, they have a fundamental importance for supply chain mitigation. In this context, this paper presents an agent-based with the support of some supply chain and risk norms to mitigate supply chain disruptions. The objective of the proposed method is to identify possible hidden supply chain risks, often highlighting previous hidden or overlooked areas of high risk. An example application for a manufacturing firm demonstrates that this model is feasible and can be replicated to different sectors.

A practical problem in automation systems modeling is the choice between a fully hybrid approach and the fluidization of some parts conserving the general discrete event approach. This paper explores the approach based on specific hybrid parts into a discrete event system using a unified Petri nets environment called GHENeSys (General Hierarchical Enhanced Net System), which follows the ISO/IEC 15909 standard and includes extensions such as hierarchy and time concepts. Then, a design method based on GHENeSys Timed Hybrid Petri Net (GTHPN) technique is proposed to model these hybrid parts. GHENeSys subnets are associated with macro-places and help to control combinatorial explosion and has extended arcs to guarantee the GTHPN applicability to practical cases. All resulting models of the approach proposed could also benefit from an easier conversion to PLC programs in IEC 61131 representation. A case study is presented for producing constructive blocks showing the advantages of the current proposition. Un problema práctico en sistemas automatizados es la selección entre el enfoque totalmente híbrido o la fluidización de algunas partes conservando el enfoque general de eventos discretos. Este articulo trata el enfoque basado en partes hibridas en un modelo discreto usando el ambiente unificado de Redes de Petri llamado GHENeSys (Sistema de Red Extendida Jerárquica General), compatible con la norma ISO/IEC 15909 incluyendo los conceptos de jerarquía y tiempo. Por tanto, se propone un método de diseño y una técnica GTHPN (Redes de Petri Temporizadas Hibridas GHENeSys) para modelar estas partes híbridas. Las subredes en macro-lugares controlan la explosión de estados y controlar transiciones mediante arcos extendidos de GHENeSys garantiza la efectividad de GTHPN para casos prácticos. Además, todo modelo resultante permite una fácil conversión a programas de PLCs en lenguajes IEC61131. Se presenta un caso de estudio para producción de bloques de construcción demostrando estas ventajas mencionadas.

Manufacturing systems must necessarily be reconfigurable to assure features of adaptability to unpredictable changes, agility, flexibility and efficiency. The reconfigurable manufacturing system (RMS) has a more adaptable perspective, because it is adjustable to the business and market interests. This reconfigurability systems behavior includes not only information processing but physical transformations and material handling. The reconfigurable manufacturing control system (RMCS) must ensures the system functionalities and the requirements of actual production line, considering the appropriate use of mechatronic and computer-aided technologies. The strategy is to reconfigure the functionality of the system or maintain critical operations so that parts affected by the fault are disabled without affecting other parts of the system. Petri net (PN) is used for description of the system behavior and conversion to a programmable logic controller (PLC) language facilitating the implementation phase, because its advantages as a technique for modeling discrete event system and its similarities to IEC60848 GRAFCET language. Therefore, this paper presents a method for design of RMCS based on PN technique and an application to control a material handling production system.

Building facilities have become important infrastructures for modern productive plants dedicated to services. In this context, the control systems of intelligent buildings have evolved while their reliability has evidently improved. However, the occurrence of faults is inevitable in systems conceived, constructed and operated by humans. Thus, a practical alternative approach is found to be very useful to reduce the consequences of faults. Yet, only few publications address intelligent building modeling processes that take into consideration the occurrence of faults and how to manage their consequences. In the light of the foregoing, a procedure is proposed for the modeling of intelligent building control systems, considersing their functional specifications in normal operation and in the of the event of faults. The proposed procedure adopts the concepts of discrete event systems and holons, and explores Petri nets and their extensions so as to represent the structure and operation of control systems for intelligent buildings under normal and abnormal situations.

Faults occurrence is inevitable in real world and a practical alternative approach is the reduction of fault consequences. Despite of this, the majority of buildings control systems do not have such mechanisms. Thus, this work proposes a procedure for the modeling of control systems for intelligent buildings which considers their functional specifications in normal operation, and in case of faults occurrence. The procedure adopts the concepts of discrete event system, holon, and Petri net and its extensions. It is presented some models derived from case studies, and mechanisms to fault-diagnosis, decision and reconfiguration.

Currently, the design of the manufacturing control systems must assure reconfiguration flexibility for agile reaction to unexpected occurrences in components in the shop-floor control level or business processes in enterprise and factory control levels. Other requirement of these control systems is ensuring collaboration and integration of heterogeneous, autonomous and distributed manufacturing subsystems to take advantages of local facilities. The combination of Holonic and Multi-Agent System HMAS and Service-Oriented Architecture SOA techniques is effective to design this Reconfigurable and Distributed Manufacturing Control System RDMCS. However, there are few methods based on formalisms which ensure a systematic workflow to implement a RDMCS considering since its abstraction phase. Therefore, this paper proposes the use of Petri net in a hybrid bottom-up and top-down design approach to combine HMAS and SOA techniques. Application examples demonstrate the modeling and effectiveness of the proposal using tools for edition, debug, simulation and generation of controller languages from the proposed models.

This paper presents the modeling of fault diagnosis mechanisms extending a method to design reconfigurable and distributed manufacturing control system. The method combines different techniques: service-oriented architecture, holonic and multi-agent system, production flow schema and input-output place-transition Petri net. An application example demonstrates advantages of the proposal, such as at cloud-based engineering, reuse, implementation and reconfiguration flexibility.

The manufacturing control system must immediately react to a variation in product, process specification, fault occurrence, changes in the resources functional capabilities, and other operational factors. Besides, to gain competitive advantage, distributed productive systems must work in cooperation with each other. To effectively integrate these heterogeneous envi-ronments, this paper proposes a method to combine holonic control system, service-oriented architecture and Petri net (PN) techniques. The PN models represent the workflow of the design method itself, the structure and the dynamic of the control system. To demonstrate the advantages of the proposal, an application example of the manufacturing system is described.

The adequate evaluation of new technologies in productive systems that perform multiple and simultaneous processes, exploring the intense sharing of resources, demands the updating of supervision and control systems. On the other hand, totally infallible systems are unviable, and for a flexible productive system (FPS) does not to suffer interruptions due to component failure, the concept of AFTCS (active fault-tolerant control system) mechanism must be adopted. In this sense, holonic control system (HCS) is considered a trend for an intelligent automation and the combination of HCS techniques and AFTCS is fundamental to assure efficiency, flexibility and robustness of FPSs. Therefore, this work presents a procedure for the modeling of active holonic fault-tolerant control system (AHFTCS) that considers AFTCS’ requirements and interpreted Petri net for the description of the systems’ behavior. This method is applied to an intelligent building (IB) as a class of FPS and the results are presented.