Arquitecturas adaptativas e cooperativas para sistemas de fabrico distribuídos

A pressão competitiva actual, é ditada por um mercado aberto e global, e no qual as empresas são confrontadas com exigências cada vez mais fortes. A adopção de novos conceitos e paradigmas de fabrico, combinados com a implementação de novas tecnologias é a resposta a estes requisitos e a solução para o incremento da competitividade. Arquitecturas de controlo distribuídas, cooperativas, auto-organizativas e heterogéneas são prometedoras neste contexto. A arquitectura apresentada, pretende solucionar de forma eficaz os requisitos dos sistemas de fabrico emergentes, sendo baseada na tecnologia de multiagentes, e implementando alguns conceitos associados aos sistemas de fabrico holónico e biónico, suportando uma nova abordagem ao controlo, que inclui as fases operacional e de reengenharia do ciclo de vida de uma empresa.info:eu-repo/semantics/publishedVersio

Predictive disturbance management in manufacturing control systems

The manufacturing systems are dynamic, non-linear and often chaotic environments, subject to the occurrence of unexpected disturbances that leads to deviations from the initial plans and usually degrades the performance of the system. The treatment of exceptions and disturbances is one major requirement to the next generation of intelligent manufacturing control systems, that should be able to treat emergency as a normal situation. In this paper, a predictive disturbance management approach that transforms the traditional “fail and recover” practices into “predict and prevent” practices, improving the control system performance, will be presented. The predictive mechanism is based in the frequency analysis of each type of disturbance to find repetitive patterns in their occurrence

ADACOR: a holonic architecture for agile and adaptive manufacturing control

In the last decades significant changes in the manufacturing environment have been noticed: moving from a local economy towards a global economy, with markets asking for products with higher quality at lower costs, highly customised and with short life cycle. In these circumstances, the challenge is to develop manufacturing control systems with intelligence capabilities, fast adaptation to the environment changes and more robustness against the occurrence of disturbances. This paper presents an agile and adaptive manufacturing control architecture that addresses the need for the fast reaction to disturbances at the shop floor level, increasing the agility and flexibility of the enterprise, when it works in volatile environments. The proposed architecture introduces an adaptive control that balances dynamically between a more centralised structure and a more decentralised one, allowing combining the global production optimisation with agile reaction to unexpected disturbances

A framework for distributed manufacturing applications

The new organisational structures used in world wide manufacturing systems require the development of distributed applications, which present solutions to their requirements. The work research in the distributed manufacturing control leads to emergent paradigms, such as Holonic Manufacturing Systems (HMS) and Bionic Manufacturing Systems (BMS), which translates the concepts from social organisations and biological systems to the manufacturing world. This paper present a Framework for the development of distributed manufacturing applications, based in an agent-based architecture, which implements some Holonic and Bionic Manufacturing Systems concepts

Implementation and validation of a holonic manufacturing control system

Flexible manufacturing systems are complex, stochastic environments requiring the development of innovative, intelligent control architectures that support agility and re-configurability. ADACOR holonic control system addresses this challenge by introducing an adaptive production control approach supported by the presence of supervisor entities and the self-organization capabilities associated to each ADACOR holon. The validation of the concepts proposed by ADACOR control system requires their implementation and experimental testing, to analyze their correctness, applicability and merits. This paper describes the implementation of ADACOR concepts in a flexible manufacturing system, verifies their correctness and applicability, and evaluates the ADACOR control system performance, considering not only quantitative indicators directly related to production parameters, e.g. manufacturing lead time, but also qualitative indicators, such as the agility

Agent-based holonic production control

Indexado ISIThe manufacturing system environment is typically a complex system, involving many variables and constraints, being in certain cases a chaotic system. The introduction of new paradigms to face globalisation, distribution of activities and customer satisfaction requirements, increases the problem complexity. The new manufacturing control approaches should support the agile adaptation to volatile technological and economical environments and should react dynamically and quickly to disturbances. This paper intends to introduce an agent-based approach to the manufacturing problem, that uses holonic concepts, is focused on distributed manufacturing shop floor control for discrete batch production, considers the optimisation of set-up and maintenance operations, and develops mechanisms for agile and fast reaction to disturbances without compromising the global production optimisation

Towards autonomy, self-organisation and learning in holonic manufacturing

This paper intends to discuss self-organisation and learning capabilities in autonomous and cooperative holons that are part of a holonic manufacturing control system. These capabilities will support the dynamic adaptation of the manufacturing control to the manufacturing evolution and emergency, specially the agile reaction to unexpected disturbances

Experimental validation of ADACOR holonic control system

In the last years, several manufacturing control architectures using emergent paradigms and technologies, such as multi-agent and holonic manufacturing systems, have been proposed to address the challenge of developing control systems capable of handling certain types of disturbances at the factory level. One of these holonic architectures is ADACOR, which integrates a set of paradigms and technologies for distributed manufacturing systems complemented by formal modelling techniques, to achieve a flexible and adaptive holonic/collaborative control architecture. The results obtained in the first experiments using the ADACOR architecture are presented in this paper, and also compared to the results produced by other control architectures. For this purpose a set of quantitative and qualitative parameters were measured, to evaluate static and dynamic performance of the control architectures

A holonic approach to dynamic manufacturing scheduling

Manufacturing scheduling is a complex combinatorial problem, particularly in distributed and dynamic environments. This paper presents a holonic approach to manufacturing scheduling, where the scheduling functions are distributed by several entities, combining their calculation power and local optimization capability. In this scheduling and control approach, the objective is to achieve fast and dynamic re-scheduling using a scheduling mechanism that evolves dynamically to combine centralized and distributed strategies, improving its responsiveness to emergence, instead of the complex and optimized scheduling algorithms found in traditional approaches

An approach to the formal specification of holonic control systems

In the manufacturing world, globalisation leads to a trend towards the reduction of batches and product life cycle, and the increase of part diversity, which are in conflict with other requirements, such as the cost reduction achieved with higher productivity. Thus, the challenge is to develop flexible, agile and intelligent management and control architectures that satisfy the referred requirements. The holonic manufacturing and the agent-based manufacturing approaches allow a new approach to the manufacturing problem, through concepts such as modularity, decentralisation, autonomy and re-use of control software components. ADACOR, one of the holonic architectures recently proposed, defines a set of autonomous and intelligent holons aiming to improve the performance of control system in industrial scenarios characterised by the frequent occurrence of unexpected disturbances. The formal modeling and validation of the specifications of the ADACOR-holons and of the interactions between these holons to implement the manufacturing control functions is of critical importance. In this paper, a formal methodology is introduced and applied to model the dynamic behaviour of the ADACOR-holon classes