5.3 Description of the M&S Approach
107
the energy state. With the defined system throughput, shift and working schedules, material requirements and production orders, the production flow component
functions as a pacemaker for the entire simulation module. The production flow
component is directly linked to the machine component. It triggers the machine
logic with events which are planned or taking place in the production flow. Planned production orders for example affect the process logic of the production
machines, as the machines must be in a production-ready state, as soon as the
production order processing time starts. The machine logic is triggered again,
when parts actually enter the individual machines of the production line.
setup line for
variant B
production
start variant A
time
no raw
material
Warm
up
Producing
Off
Set
up
Producing
Idle
Standby
Off
events in the
material flow
component
behavior
machine x
(machine
component)
energy profile
of machine x
(energy
component)
Figure 5.13 Energy profile creation depending on the events in the material flow and the
resulting machine behavior
The delay in material flow a machine causes is not defined in the DES material
flow model, as it would be done in a purely process-oriented simulation model
but is calculated summing up the process times of the single operating states of
the machine logic.
Example: Machine A is turned on at 6 am for production start and must go through a 35minute warmup process. Due to raw material supply issues, the raw material is brought
to the line late at 6:45 am. The machine has a cycle time of 4 minutes per part and the
lot size of the planned production order is 80 pieces. The delay machine A causes in
the production flow before the first part is handed over to machine B for processing
therefore sums up to 49 minutes instead of the originally planned 39 minutes.
107
the energy state. With the defined system throughput, shift and working schedules, material requirements and production orders, the production flow component
functions as a pacemaker for the entire simulation module. The production flow
component is directly linked to the machine component. It triggers the machine
logic with events which are planned or taking place in the production flow. Planned production orders for example affect the process logic of the production
machines, as the machines must be in a production-ready state, as soon as the
production order processing time starts. The machine logic is triggered again,
when parts actually enter the individual machines of the production line.
setup line for
variant B
production
start variant A
time
no raw
material
Warm
up
Producing
Off
Set
up
Producing
Idle
Standby
Off
events in the
material flow
component
behavior
machine x
(machine
component)
energy profile
of machine x
(energy
component)
Figure 5.13 Energy profile creation depending on the events in the material flow and the
resulting machine behavior
The delay in material flow a machine causes is not defined in the DES material
flow model, as it would be done in a purely process-oriented simulation model
but is calculated summing up the process times of the single operating states of
the machine logic.
Example: Machine A is turned on at 6 am for production start and must go through a 35minute warmup process. Due to raw material supply issues, the raw material is brought
to the line late at 6:45 am. The machine has a cycle time of 4 minutes per part and the
lot size of the planned production order is 80 pieces. The delay machine A causes in
the production flow before the first part is handed over to machine B for processing
therefore sums up to 49 minutes instead of the originally planned 39 minutes.