Paul Valckenaers

Holonic and multi-agent systems for manufacturing

Invited Talks.- The Past, Present, and Future of IEC 61499.- Can Multi-Agents Wake Us from IC Design Productivity Nightmare?.- Motivation.- From Intelligent Agents to Intelligent Beings.- Multi-agent Reflection in Autonomic Systems.- Auctions with Arbitrary Deals.- Architectures and Services.- Service Composition in Holonic Multiagent Systems: Model-Driven Choreography and Orchestration.- Flexible Roles in a Holonic Multi-Agent System.- Agent-Based Inter-Organizational Workflow Management System.- Co-operative Co-evolutionary System for Solving Dynamic VRPTW Problems with Crisis Situations.- Anonymity Architecture for Mobile Agent Systems.- SitCom - Development Platform for Multimodal Perceptual Services.- New Technologies and Techniques.- An Ontology-Based Reconfiguration Agent for Intelligent Mechatronic Systems.- Methods to Observe the Clustering of Agents Within a Multi-Agent System.- Distributed Director Facilitator in a Multiagent Platform for Networked Embedded Controllers.- Agent Methods for Network Intrusion Detection and Response.- Detecting Intrusions in Agent System by Means of Exception Handling.- Smart Caching Algorithm for Software Agents Based on Re-execution Probability.- Planning and Scheduling.- Metaheuristic Agent Teams for Job Shop Scheduling Problems.- Distributed Production Scheduling Using Federated Agent Architecture.- A Study on Real-Time Scheduling for Holonic Manufacturing Systems - Simulation for Estimation of Future Status by Individual Holons.- Adaptive Planning for Supply Chain Networks.- An Agent Based Modelling Approach for Stochastic Planning Parameters.- Design Issues.- A Holonic Metamodel for Agent-Oriented Analysis and Design.- Using Adaptable Design to Classify Interactions Within a Distributed Control Architecture.- Application of the Holonic Approach in Distributed Control Systems Designing.- Design and Implementation of Adaptive Agents for Complex Manufacturing Systems.- Dynamic Configuration and Management of e-Supply Chains Based on Internet Public Registries Visited by Clusters of Software Agents.- Applications.- A Multiagent Control System for Shop Floor Assembly.- MagentaToolkit: A Set of Multi-agent Tools for Developing Adaptive Real-Time Applications.- On Practical Implementation of Holonic Control Principles in Baggage Handling Systems Using IEC 61499.- Zero Downtime Reconfiguration of Distributed Automation Systems: The ?CEDAC Approach.- Holonic Multiagent-Based System for Distributed Control of Semi-industrial Pilot Plants.- Collision Avoidance Algorithms: Multi-agent Approach.- Creating Contract Templates for Car Insurance Using Multi-agent Based Text Understanding and Clustering.- Multi-agent-Based Diagnostics of Automotive Electronic Systems.- PIHolS Workshop.- Performance in Industrial Holonic Systems.- Towards Industrial Strength Business Performance Management.- Ontology-Based Competence Management for Team Configuration.- Information Agents Handling Semantic Data as an Extension to Process Monitoring Systems.- Applications of Virtual Reality in Design and Simulation of Holonic Manufacturing Systems: A Demonstration in Die-Casting Industry.- Resilience in the Face of Disaster: Accounting for Varying Disaster Magnitudes, Resource Topologies, and (Sub)Population Distributions in the PLAN C Emergency Planning Tool.- Holonic Simulation of a Design System for Performance Analysis.

Holonic manufacturing systems

This chapter presents the earlier results in our development of a holonic manufacturing systems framework, with a clear emphasis on manufacturing and logistics. The insights discussed in the previous chapters were used as precious guidelines and as a check for soundness when comparing options. In particular, design for the unexpected (low and late commitment) and maximizing the potential for achieving critical user mass were important factors influencing the choices made during the development activities.

Holonic manufacturing execution systems

Abstract This paper presents the design of a holonic manufacturing execution system. The design is an instantiation of the PROSA reference architecture [1] augmented with coordination and control mechanisms inspired by natural systems – i.e. food foraging behavior in ant colonies. Research prototypes are implemented as multi-agent systems. The main coordination and control mechanisms ensure that the process plans are properly executed and emergently forecast the workload of the manufacturing resources as well as well as lead times and routings of the products. The design empowers the product instances to drive their own production; the coordination is completely decentralized. In contrast to many decentralized designs, the manufacturing execution system predicts future behavior and proactively takes measures to prevent impending problems from happening. A social control mechanism ensures that product instances adhere sufficiently to their declared intentions, which is necessary to guarantee adequate forecast accuracy. The design has been applied to an industrial test case, and the paper discusses results of this case study.

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.

A conceptual framework for holonic manufacturing: Identification of manufacturing holons

Future manufacturing systems will need to cope with frequent process disturbances and changes in production orders. Therefore, their control will require constant adaptation and high flexibility. Holonic manufacturing is a highly distributed control paradigm that promises to handle these problems successfully. It is based on the concept of autonomous cooperating agents, called “holons”. This paper presents the conceptual framework that is needed for the development of holonic manufacturing systems (HMS). The paper defines the identification task of the manufacturing holons as the first task in the development process and shows the role of a holon taxonomy herein. The holon taxonomy is based on orders, products, and resources as basic building blocks. They are structured using object-oriented design concepts like aggregation and specialization. Additional staff holons provide the basic holons with specialized advice. The resulting architecture fulfills the requirements for holonic manufacturing, where the autonomy of the agents provides the system with the ability to react to disturbances, while the existence of hierarchical control elements provides the system with opportunities for global optimization. The resulting architecture remains flexible, allowing control strategies ranging from very hierarchical to very heterarchical. A case study is given featuring the PMA testbed HMS.

Self-organisation: paradigms and applications

A self-organising system functions without central control, and through contextual local interactions. Components achieve a simple task individually, but a complex collective behaviour emerges from their mutual interactions. Such a system modifies its structure and functionality to adapt to changes to requirements and to the environment based on previous experience. Nature provides examples of self-organisation, such as ants food foraging, molecules formation, or antibodies detection. Similarly, current software applications are driven by social interactions (negotiations, transactions), based on autonomous entities or agents, and run in highly dynamic environments. The issue of engineering applications, based on the principles of self-organisation to achieve robustness and adaptability, is gaining increasing interest in the software research community. The aim of this paper is to survey natural and artificial complex systems exhibiting emergent behaviour, and to outline the mechanisms enabling such behaviours.

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.

Self-organising in multi-agent coordination and control using stigmergy

In order to cope with todays dynamic environment, the described manufacturing control system is designed as a self-organising multi-agent system. The design of this novel system implements the PROSA reference architecture [1]. Coordination among agents is done indirectly through a pheromone-based dissipative field as is done by social insects in coordinating their behaviour. In this case, our agents act as social insects interpreting the pheromones put by the others in the environment. This control system is built from the basic elements of any manufacturing controller, namely products, resources and orders. However, the overall control system is constructed not only from those basic elements but also employing the appropriate interaction patterns among the agents who represent them. For coordination purposes, the agents send out a kind of mobile agents - artificial ants - to lay down information on the environment. In our case, where fulfilling the manufacturing orders is the main concern, there are at least 3 types of ant in this system: (1) feasibility ants - to propagate information concerning the feasible finishing routes; (2) exploring ants - to explore the feasible routes; and (3) intention ants - to propagate the route preferences. The overall mechanism enables the system to exhibit a self-organising behaviour.

Multi-agent Coordination and Control Using Stigmergy Applied to Manufacturing Control

This manuscript discusses multi-agent coordination and control using techniques inspired by the behavior of social insects. It presents a system design that enables desirable overall behavior to emerge without exposing the individual agents to the complexity and dynamics of the overall system. The research, which this paper discusses, focuses on manufacturing control. However, the approach remains applicable to the coordination and control of other types of ironware systems (e.g. traffic, supply chain...).

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.