The reaction of the developed system in the case
of tool wear is shown in Figure 11. Steps of this case
are explained as follows:
- Input disturbance shown by turning on the red
light (alarm) at PLC 1.
- PLC 1 sends the signal to agent.
- OPC protocol is used for communicating
between PLC and agent.
- Agent diagnoses the disturbance type.
- If the disturbance belongs to the non-negotiation
type, agent generates a new plan and sends the
command to PLC.
- The system overcomes the disturbance shown by
turning on the green light at PLC 1.
The reaction of the developed system in the case
of machine breakdown is shown in Figure 12. Steps
of this case are explained as follows:
- Input disturbance shown by turning on the red
light (alarm) at PLC 1.
- PLC 1 sends the signal to agent.
- Collecting data.
- Agent diagnoses the disturbance belonging to the
negotiation type.
- Agents establish the wireless network to server
- Agent negotiation as shown in Figure 13.
- An appropriate agent is selected for carrying out
the job of the failure machine.
- The system overcomes the disturbance shown by
turning on the green light at PLC 2.
Figure 12: Reaction of the agents in the case of machine
breakdown.
5 CONCLUSIONS
Cognitive agents enable the manufacturing system to
adapt flexibility to changes and disturbances without
upper level aids or a total planning modification. In
the cognitive agent based manufacturing, the
cognitive capabilities such as perception, reasoning,
and cooperation are equipped for resources on the
shop floor. In order to prove the efficiency of the
proposed cognitive agent concept, the test-bed was
implemented and focused on the self-adjustment
mechanism in the case of the disturbances. The
experimental results show that the mechanism of the
proposed system enables the system to adapt to the
disturbances successfully.
Figure 13: Agent negotiation process.
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