March 29th - 31st 2002 SwarmFest 2002 1
SMS:a Spinning Mill Simulator
made in Swarm
[email protected] Morini
Centre for Employment Studies “LABORatorio R. Revelli”
http://www.labor-torino.it
March 29th - 31st 2002 SwarmFest 2002 2
Production management:the problem
• Matching orders and production units (PU)
• Appropriate sequencing of each chain
• Who is supposed to do what AND in which sequence?
GANTT DIAGRAM
0 5 10 15 20
Filatoio 1
Filatoio 2
Filatoio 3
Filatoio 4
March 29th - 31st 2002 SwarmFest 2002 3
Production Constraints
• Timely delivery
• “Soft” technical constraints
• “Hard” technical constraints
March 29th - 31st 2002 SwarmFest 2002 4
Solutions’ evaluation
• Modelling the firm’s supply chain• Simulating the production process for each
order• Accounting for:
– Set-ups– Lead times– Technical similarity of products in a row– Speed of heterogeneous PUs
March 29th - 31st 2002 SwarmFest 2002 5
Search for good production plans
• GA (G. Ferraris’ Genetic Manipulator)
• Each solution is coded in form of a binary string
• The SCN model can evaluate each plan’s fitness in terms of –tC (minus total costs)
March 29th - 31st 2002 SwarmFest 2002 6
Fitness evaluation (in-depth)
• Delay costs
• Setup costs
• Misplacing order costs
• Average count costs
• Overlaying setups costs
March 29th - 31st 2002 SwarmFest 2002 7
Fitness evaluation (in-depth)
• Delay costs
• Setup costs
• Misplacing order costs
• Average count costs
• Overlaying setups costs
March 29th - 31st 2002 SwarmFest 2002 8
Fitness evaluation(Delay & setup)
Lot size
Cost
Setup cost
Delay ‘cost’
Total cost
March 29th - 31st 2002 SwarmFest 2002 9
Late deliveries’ ‘cost’Cost
Delay
1 to 3 days
4 to 8 days
9+ days
March 29th - 31st 2002 SwarmFest 2002 10
Set-up costs
Set-up
Cost (time)
Perfect matching
Rotor substitution
Card substitution
Rotor & Card substitution
March 29th - 31st 2002 SwarmFest 2002 11
Fitness evaluation (in-depth)
• Delay costs
• Setup costs
• Misplacing order costs
• Average count costs
• Overlaying setups costs
March 29th - 31st 2002 SwarmFest 2002 12
• Different yarns need different bobbins– Cylinder-shaped, ready for dyeing– Cone-shaped, ready for weaving
• Extremely urgent deliveries may end being made on the wrong kind of PU
• Re-winding a certain amount of product has a known cost, epxressed in money/kg.
Misplaced orders costs
March 29th - 31st 2002 SwarmFest 2002 13
Fitness evaluation (in-depth)
• Delay costs
• Setup costs
• Misplacing order costs
• Average count costs
• Overlaying setups costs
March 29th - 31st 2002 SwarmFest 2002 14
Average count costs‘Cost’
Count
Optimal average count
Preceeding and subsequent departments shortage
Preceeding and subsquent departments saturation
March 29th - 31st 2002 SwarmFest 2002 15
Fitness evaluation (in-depth)
• Delay costs
• Setup costs
• Misplacing order costs
• Average count costs
• Overlaying setups costs
March 29th - 31st 2002 SwarmFest 2002 16
Overlapping (interfering)setup costs
‘Cost’
# simultaneous setups
5
4
6
0 to 3
March 29th - 31st 2002 SwarmFest 2002 17
The planner:evolution and working modes
1. RANDOM planner (1)
2. Explicit rules (failed attempt) (2)
3. Optimizing by Genetic Algorithms (3)
4. Applying a human-made program (4)
March 29th - 31st 2002 SwarmFest 2002 18
Comparing results
• Total costs obtained on test case:– (1): random 100.00– (3): GA (5’ run) 68.75– (3): GA (30’ run) 62.25– (3): GA (6h run) 60.62– (4): hand made by human planner 82.27
March 29th - 31st 2002 SwarmFest 2002 19
Encoding sequences intobinary strings
1
2
3
8
7
5
4 6
102
3 11
9
• From base10 into base2 (using enough bits)
[8 1] [7 2] [4 3] [5 1] [3 2] [6 3] [2 1] [11 2] [9 3]
• Semantics is lost from the GA perspective[1000 01] [0111 10] [0100 11] [0101 01] [0011 10] [0110 11]...
100001011110010011010101001110011011...
March 29th - 31st 2002 SwarmFest 2002 20
Solutions’ evolution graph
March 29th - 31st 2002 SwarmFest 2002 21
SMS in action (w/GUI)
March 29th - 31st 2002 SwarmFest 2002 22
SMS’ batch mode: sms –b
• EC grant (project Penelope):– Cordis Fifth Framework IST programme – http://www.cordis.lu/fp5/home.html
• SMS to become part of a bigger framework
• SMS as the engine of a web-based production planning service
March 29th - 31st 2002 SwarmFest 2002 23
SMS is ERA compliant
March 29th - 31st 2002 SwarmFest 2002 24
SMS:a Spinning Mill Simulator
made in Swarm
[email protected] Morini
Centre for Employment Studies “LABORatorio R. Revelli”
http://www.labor-torino.it
