INTRODUCCIN

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INTRODUCCIÓN
Multi-agent Paradigm

• Intelligent distributed monitoring
• Architecture for Flexible Manufacturing Systems

Based on
Co-operate to achieve
Heterogeneous resources
FMS Monitoring Functions
Society of cognitive agents
Modeled as
FMS
Monitoring
Sufficient Knowledge for the decision-making
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INTRODUCCIÓN
Need adaptability in production structures
Continuosly increasing
-Increase in competition -Decrease product life
cycle
Cycle, due date inventory level
Efectiveness of a production
Flexibility and reacticity to integrate the
evolution of the market
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INTRODUCCIÓN

• Multi Agents
• Systems (MAS)

- More Suitable for dynamic monitoring - Build
Complex and flexible advanced intelligent
systems
Monitoring Systems
More - decentralized - emergent - concurrent
Than - centralized - planned - sequential
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Multi-agent Architecture for Distributed and Real
Time Monitoring
Functions - Error detection - Error diagnosis -
Error handling

• Monitoring
• systems

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Multi-agent Architecture for Distributed and Real
Time Monitoring
Under the responsability a RMA handle Local
rules and enviromental information to perform
the monitoring functions
Network of cognitive agents RESOURCE
MONITORING AGENTS (RMA)
Replace a Centralised monitoring
Each resource

• MAADM

Dynamic interaction of the agents in real-time
Overall system perfomance
EMERGE
It is not globally planned
CONTRACT NET PROTOCOL
The architecture receives the tasks to execute in
the FMS
INTERFACE
Task Manager Agent
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MAA- The monitoring of the
FMS is distribuited over the RMAs- Global
Monitoring is achieved by passing appropiate
messages between the RMAs- The Contract Net
Protocol is used to co-ordinate and co-
operate the RMAs, and ro reshedule the operations
in failure
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Resource Monitoring Agent Model
- Knowledge - Control ( Reasoning ) -
Co-operation - Communication

• Cognitive
• Agent
• Model

Distinguishes
TYPES - Self-Knowledge own information for
monitoring its resource (resource state
database, diagnosis production rules and error
hendling production rules) - Other Knowledge
information about other RMAs, wich can operate
whit him
Knowledge (internal and external activities)
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Resource Monitoring Agent Model
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Resource Monitoring Agent Model
TYPES OF MESSAGES - Information request messages
part dimensions, part weight,presence or no
presence of the part, resource status, tools
status, etc - Failure Alert Messages resource
in failure, tool in failure, etc - Cooperation
and co-ordination messages contracts, bids,
acknowledgements, etc
Communication (synchronous and is done by
sending messages)
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Resource Monitoring Agent Model
SET OF METHODS - Detection It interacts with
the resources status database to detect the
abnormal situations ocurring on each resource. -
Diagnosis It identifies and recognises faults,
using a rule-based expert system. The knowledge
bse is a set of production rules. If event1 and
eventn then fault1,........,faultm - Error
Handling It determinate the corrective actions
that handle the faults. They areresheduling,
urgent halt, transit to degradaded mode, operator
call and actionleap - Contract Net Protocol
Control (RMAs decision-making capability to
acomplish the monitoring functions and
to co-operate with others agents)
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Resource Monitoring Agent Model
RESCHEDULING It reschedules locally operations
that couldnt be executed by the resource in
failure using the Contract Net Protocol,
developed to resolve the problem of dynamic
scheduling in FMS. - Detection It interacts
with the resources status database to detect the
abnormal situations ocurring on each resource. -
Diagnosis It identifies and recognises faults,
using a rule-based expert system. The knowledge
bse is a set of production rules. If event1 and
eventn then fault1,........,faultm - Error
Handling It determinate the corrective actions
that handle the faults. They areresheduling,
urgent halt, transit to degradaded mode, operator
call and actionleap - Contract Net Protocol
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Contract Net Protocol
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Propagación de Requisito
Agente Recurso Manager
Requisito (OP0)
Requisito (OP0)
Requisito (OP2)
Requisito (OP1)
Requisito (OP1)
Requisito (OP2)
Requisito (OP4)
Requisito (OP3)
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Realimentación de Petición
Agente Recurso Manager
Petición (OP0)
Petición (OP0)
Petición (OP2)
Petición (OP1)
Petición (OP1)
Petición (OP2)
Petición (OP4)
Petición (OP3)
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Propagación de Contrato
Agente Recurso Manager
RA11
RA21
RA31
RA41
RA51
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Realimentación de Aceptación y Cancelación de
petición
Agente Recurso Manager
RA11
RA32
RA21
RA52
RA42
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Resolución de conflictos e incertidumbres
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Conclusiones
Las principales ventajas de la arquitectura
propuesta son flexibilidad en un ambiente
variable, reconfiguración y adaptibilidad
inherente, tolerancia a fallos rápida y
eficiente, desarrollo modular y autonomía
operacional.
Los resultados experimentales obtenidos en la
simulación, demostraron que la arquitectura
multiagente is una plataforma de trabajo
bastante apropiada para monitorización
distribuida y en tiempo real de FMS.
La implementación de la arquitectura multiagente
fue llevada a cabo en Java por ser orientada a
objetos, distribuida, segura, dinámica y
programación de alto desempeño. El Java Expert
System Shell fue integrado en el software, para
el desarrollo del sistema experto basado en
reglas, usado en el diagnóstico y manejo de
error.