Controle supervisório modular de sistemas de manufatura

Abstract

This paper proposes a methodology for the synthesis of optimal supervisors for automated manufacturing facilities. The methodology is based on local modular supervisory control, an extension of the Supervisory Control Theory with the goal of avoiding states explosion in the modeling and synthesis of supervisors. The modeling consider that manufacturing systems are characteristically formed by several concurrent subsystems that should be synchronized in way to obey a series of specifications. The synthesis process exploits modularity of specifications, as well as the natural decentralized structure of manufacturing systems, to generate minimally restrictive supervisors with reduced number of states. The proposed methodology is applied to a hypothetical example of integrated manufacturing system. The results show considerable reduction of the computational complexity and of the size of supervisors.

Multitasking Supervisory Control of Discrete-Event Systems

“…Finally, we presented some results on the property of reversibility that lead to an alternative approach for ensuring liveness of multiple tasks. This approach could have been successfully applied to the examples, but certainly there are problems where reversibility would be too strong a constraint (de Queiroz, 2004).…”

“…Finally, we investigate the use of reversibility as an alternative way of ensuring liveness of multiple tasks. The results presented in this paper have been developed in the first author's doctoral work (de Queiroz, 2004) in close cooperation with the other authors.…”

“…The simplicity of this example helps understanding the multitasking model, but it does not really make its usefulness apparent. The second example, which deals with diverse liveness and safety specifications over a hypothetical flexible manufacturing system (de Queiroz, 2004), demonstrates the convenience of the use of CMG in the synthesis of multitasking supervisors. This example also illustrates how a set of new tasks E can be introduced by the specifications.…”

Application of the supervisory control theory in the project of a robot-centered, variable routed system controller

“…For this end, it is made use of the SCT [12] and its Local Modular approach [10] as tools for the modeling and synthesis of the control system. The model proposed in [11] is used for the control architecture elaboration.…”

Metodologia e ferramenta de apoio ao teste de não-conflito no controle modular de sistemas a eventos discretos

“…Nesse caso, o modelo de alto-nível esconde eventos que correspondem a detalhes operacionais do comportamento do sistema, não-relevantes no mundo gerencial. Abstrações têm sido ainda usadas no controle modular (Wonham e Ramadge, 1988), (de Queiroz e Cury, 2000), (de Queiroz e Cury, 2002), como um meio de aliviar a carga computacional do teste de não-conflito entre supervisores sintetizados por uma abordagem de controle modular. Nesse caso, o comportamento em malha fechada decorrente da ação de cada supervisor localé abstraído, e o teste de não-conflitoé realizado sobre o conjunto de abstrações obtidas (Feng e Wonham, 2006), (Pena et al, 2006a), (Pena et al, 2006b), (Hill e Tilbury, 2006), (Hill, Tilbury e Lafortune, 2008).…”