nan Hadeli

Multi-agent coordination and control using stigmergy

This paper describes and discusses a novel design and a prototype implementation for manufacturing control systems, aimed at handling changes and disturbances. This novel design utilizes the concept of a multi-agent system. Agents in this system use an indirect coordination mechanism, called stigmergy. Stigmergy is a class of mechanisms that mediate animal-animal interactions. It consists of indirect communication that is taking place between individuals of an insect society by local modifications induced by these insects on their environment. The coordination mechanism in this paper is based on a technique used by food foraging ants. Food foraging ants provide the inspiration by the manner in which they spread information and make global information available locally; thus, an ant agent only needs to observe its local environment in order to account for nonlocal concerns in its decisions. A prototype was built to test the coordination technique. The prototype comprises a flexible manufacturing system model/emulation that has dynamic order arrival, probabilistic processing time, and some general perturbations such as machine breakdowns. The prototype served to investigate a specific research question: is it possible to create short-term forecasts based on the intentions of the agents. It has been intentionally kept simple to facilitate the understanding of what is happening in the system. Size and complexity of the prototype implementations are being augmented gradually in ongoing research.

On the design of emergent systems: an investigation of integration and interoperability issues

Abstract Many useful manmade systems in this world are extremely complex; a typical example is a large infrastructure. No design team ever invents these artifacts because they are too complex. These artifacts are made by combining existing elements (legacy) and by building new subsystems without explicit and comprehensive up-front coordination. To a large extent, these complex systems emerge and evolve. Experience shows that designers frequently fail to develop artifacts that, when combined, facilitate the emergence of effective and efficient systems. This paper formally elaborates the mechanism behind this phenomenon, and proposes principles for the design of components for emergent systems. The above insights were gained during the development of research prototypes for multi-agent manufacturing control; manufacturing systems are notorious for experiencing integration and interoperability problems as described above. Consequently, the design principles are discussed and illustrated on the design of multi-agent manufacturing control systems but also on work by others. Finally, although this paper mainly discusses the above in a generic fashion, and although the generic statements hold in an application-independent manner, it is important to appreciate that the applicability of the above insights and principles has significant limitations, which are discussed in the paper.

Emergent short-term forecasting through ant colony engineering in coordination and control systems

Abstract This manuscript presents a design for the emergent generation of short-term forecasts in multi-agent coordination and control systems. Food foraging behavior in ant colonies constitutes the main inspiration for the design. A key advantage is the limited exposure of the software agents in the coordination and control system. Each agent corresponds to a counterpart in the underlying system and can be developed and maintained exclusively based on knowledge about its counterpart. This approach to make non-local information available without exposing the software agents beyond their local scope is the research contribution and focus of the discussion in this paper. The research team applies this design to multi-agent manufacturing control systems and to supply network coordination systems, but its intrinsic applicability is broader.

MAS coordination and control based on stigmergy

This paper discusses a multi-agent coordination and control system. The system implements the PROSA architecture [12] and uses a specialized approach to stigmergy. This approach is discussed in relation to more commonplace designs based, for instance, on negotiation protocols. Next, the discussion focuses on the commonalities and differences between the source of inspiration for the system design - food foraging in ant colonies - and the resulting coordination control system itself. In particular, the discussion reveals that the multi-agent coordination and control system is based on deeper insights rather than a superficial translation of the biological example.

A benchmarking service for the manufacturing control research community

This paper presents the development—by the IMS Network of Excellence (cf. http://www. ims-noe.org)—of a web-based benchmarking service for manufacturing control systems. The paper first discusses the rationale behind this development. Next, the architecture and usage of the benchmarking service is presented and illustrated. Finally, the paper addresses the current status of the benchmarking service.

A study of system nervousness in multi-agent manufacturing control system

This paper discusses a study on system nervousness in a multi-agent manufacturing control system. Manufacturing control systems, built along this approach, are able to generate short-term forecasts that predict both resource loads and order routings. These forecasts become known throughout the multi-agent system with some time delay. If the agents make their decisions based on these forecasts, proper measures need to be taken to account for these delays, especially when disturbances (rush orders, machine breakdowns) occur. If agents react too eagerly and swiftly, the forecasts become unreliable. This paper studies this issue and the measures in the control system design that address the problem. More precisely, the agents behave in a socially acceptable manner that reconciles adaptation to changed circumstances with predictability.

Multi-Agent Manufacturing Control: An Industrial Case Study

Abstract The paper discusses the development of a multi-agent manufacturing control system for an industrial application. This multi-agent system follows the PROSA reference architecture and applies ail ant colony design (stigmergy) to provide coordination and emergent forecasting services. The paper first presents the experimental set-up: • The properties of this shop and its particular challenges to control systems • The emulation of an existing production shop in industry • The multi-agent system connected to this emulation Next, the paper discusses the real-time aspect of the emulation. Third, the multiagent control system is presented. Filially, the paper discusses the browser to analyze the results generated during simulation runs

Coordination and control for railroad networks inspired by manufacturing control

This paper presents a multi-agent coordination and control system for railroad networks. The system is an extension of a framework that implements the PROSA reference architecture augmented with forecasting mechanisms. PROSA targets coordination & control problems in manufacturing environments. The existing framework was extended for railroad control without requiring any significant changes to the PROSA framework itself. The forecasting capabilities of the framework were used to create a robust railroad controller. By using forecasting mechanisms, train services are able to anticipate and avoid impending problems. The development revealed how the extensions, needed for railroad networks, are equally useful for certain manufacturing control tasks

PRODUCTION PLANNING AND CONTROL IN BIO-INSPIRED HOLONIC MANUFACTURING EXECUTION SYSTEMS

Abstract In manufacturing systems, production planning and control performs a key function. This paper discusses the production planning and control (PPC) aspects of a Bio-Inspired Holonic Manufacturing Execution Systems. The PPC system in such a bio-inspired system has a design that distinguishes it from more conventional systems. This design renders the PPC system robust and responsive when facing changes and disturbances that occur on a shop floor.

Intelligent Product = Intelligent Agent + Intelligent Being

The notion of an intelligent product calls for research into suitability for integration as it aims for coordination and integration on an unprecedented scale. This is particularly challenging where it affects the core businesses of companies. Moreover, these integration issues go well beyond IT interoperability. This paper presents a novel concept the intelligent being as a means to achieve suitability for integration at this scale. The paper argues for a major role of the intelligent being in production and logistic systems analogous to the undeniably prominent role of maps in navigation systems. The concept of an intelligent being contributes to the design and development of complex adaptive systems by enabling integration and coordination at an unprecedented scale: the corresponding reality is the limit.