Transcript Control of a flexible manufacturing cell by Petri nets in Java language

Control of a flexible
manufacturing cell by Petri
nets in Java language.
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Objetives

Configurating the PCI SC/I-T controller
board via CMD’s HLI.

Create a set of Java classes that can
access to the bus.

Create a Java implementation of Petri nets
to control the manufacturing cell via
Interbus.
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The PCI SC/I-T controller board
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4th. Generation
Interbus controller
board.
Remote interface for
PCI bus.
Total configuration of
the controlled system
process data by CMD
software.
Permits permanent
storage of process
data in its EEPROM
memory.
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Interbus
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CMD
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Phoenix-Contact bus configuration software
Can export bus configuration to a high-level
languaje.
Auto-configuration.
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JNI
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Interconnect Java with C libraries.
 Solution: changing the C functions
created by HLI for being used from a Java
application.
 Java provides this funcionality: JNI (Java
Native Interface).
 Now we only have to find a method for
representing the system to control: Petri
nets.
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Java programming
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Petri nets

Petri nets (PN) are a modelling and analysis tool
especifically adapted to the study of discrete
events systems.
 A set of classes have been implemented for
representing a PN: Place, Transition, Net.
 Two ways for creating a PN: direct code writing or
importing a PN from an external editor.
 We have used HPSim, a free PN editor that exports
a PN into a .txt file; the class TextToNet translates
the created PN into a Net object inside our project.
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Inicialization
net
Station automatic
production
independent nets
Global control net
Petri nets
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Control
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Class Coordinator implements the
evolution of the PN: habilited transitions,
fires and marking. Actualizates the
monitor/s values.
 Monitors hold the variables: station inputs
and outputs, array of orders, etc.
 After a fixed delay the class BusManager
actualizates the station output variables
from the monitor objects values and
actualizates from the bus the input values.
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Xplore project Members
Video (Media Player)
Ramón Piedrafita Moreno
Alberto Gran Tejero
Oscar García Flores
Video (Quicktime)
Universidad de Zaragoza
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