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This paper presents a framework based on Petri Net (PN) and Multi Agent System (MAS) techniques for modeling autonomous multi-robots systems, which require high interaction among the robots (in some cases with humans), synchronization of movements, implementation of cooperation strategies, and a strong notion of the physical environment. The framework considers all phases of the developing process, starting with the abstraction phase and going up to the implementation of the model, to ensure an efficient and flexible approach for specifying the proposed control system architecture. An application example details this solution, in which multi-robots systems can perform tasks and collaborative behaviors considering the cited requirements.

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.

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.

Available industrial standards do not explicitly consider how to treat sustainability indicators in PS design and its control system. Therefore, this paper proposes a framework to systematize the performance evaluation process for industrial PS considering indicators that qualify and quantify its sustainability. The framework adopts Petri net technique and extensions of the standard ANSI/ISA95. Simulation-based analysis, decision making techniques and a PS´s classification based on product green seal are also considered. Furthermore, the framework considers the processing information, storing and accessing each component using a Cyber Physical Technology due to the trend of PSs to be, in fact, a network for companies that are, in general geographically dispersed.

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.

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.

Manufacturing control systems must quickly react to variations of product, process specifications, fault occurrence, changes in the resources functional capabilities, and other operational demands. Besides, to gain competitive advantages, dispersed manufacturing systems must cooperate with each other. The combination of holonic control system and service-oriented architecture techniques can be effective to integrate these heterogeneous environments since the agents must also cooperate to achieve their services. Therefore, this paper introduces a service-oriented and holonic control architecture using Petri net to represent the workflow of design method itself, structure and dynamic of the entities. The modeling of an example is presented to demonstrate application at self-organization and adaptation, fault treatment, degeneration, and relatively shorter implementing time.

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.