process design games
TRANSCRIPT
7/29/2019 Process Design Games
http://slidepdf.com/reader/full/process-design-games 1/16
Process design - how many squares?
Edit 0 0 6 …
Process design - how many squares do you see?
20100407. Mapping process. How many squares. Slides.pptx • DetailsDownload64 KB
I use this little exercise to illustrate the value of mapping processes.
1. Show this slide (see slide attachment) and tell the students they will have
30 seconds to answer the question on the next slide on their own with no
discussion.
2. Show the slide with the sqaures on and give students 30 seconds, then
switch back to the previous slide.
3. Ask each student (or a selection in a big class) how many squares they saw.
You’ll have a range of answers, so note them on the board.
4. Then say ‘Good, that was very interesting. Now’s let’s move onto today’s
lecture on process mapping.’ …..pause…..there will be a little confusion,
because they will be expecting a definitive answer.
5. Take them back to the slide with the squares on it and remind the students
of the question – “How many squares do you see?” As such, they’re all right,
because the quest ion is about perceptions, it’s about what each individual
sees, NOT the reality. You can then discuss the value of mapping processes.
Because everyone sees the process differently, before you try to improve a
process, you need to reach a common understanding of what the process
looks like. This leads nicely into the lecture on process mapping and works
with students at all levels.
his game is self explanatory once you read through the document - a frienduses this in his project management class to illustrate team dynamics (bothgood and bad). The reference for this game is as follows:
Hedges,P, K. Pedigo. 2002 What's Happening in Your Neighborhood? An
7/29/2019 Process Design Games
http://slidepdf.com/reader/full/process-design-games 2/16
Experiential Exercise for Teams. Journal of Management Education.Volume 26, #3.
Overview: The class is broken up into groups. Each person in the group isgiven a few statements. The groups can only complete their mission once
they piece together the different statements. This exercise requireslistening and full participation by all group members. It helps to explain whysome projects go so terribly wrong. A full version of this can be playedonline in World of Warcraft.
Some Useful Videos
Edit 0 0 1 …
Hi,
Here are some videos I use for various types of input into a class:
I've found the clip of the Asda Warehouse operation. It's
interesting to contrast with Ocado, Asda use voice picking. This
can be used to discuss how planning precedes control, and how the
capacity of the system is used carefully not to have too many short
shelf life goods hanging around at the warehouse. This can be used
with MBAs
http://news.bbc.co.uk/1/hi/business/7788605.stm
This clip look at a mail order company, 'the present' company. It is
a good clip as it shows end to end operations from catalogue
design to despatch, here they use traditional pick lists to pick from.
It's a good opener for any operations class by asking WHY the
business is set up in this way. I also ask how it may be improved.
http://news.bbc.co.uk/1/hi/uk/7782634.stm
Next Amazon, who use traditional 'barcode' scanners for picking. I
usually ask 'What do you think the Amazon warehouse looks like?'
I then get people to speculate about what type of technology is
used, and how the layout is set up. People often are surprised at
7/29/2019 Process Design Games
http://slidepdf.com/reader/full/process-design-games 3/16
Amazon is set up in this way.
http://news.bbc.co.uk/1/hi/business/7771268.stm
Finally thought you might like this clip of the 'Goodfellows' pizzafactory in Ireland. I've toured similar factories, what this doesn't
show is the traceability aspect which is key to manufacturing food.
It does give some insight into high volume, low variety products.
Useful also for exploring what changes could be made, and how
this relates to changes in process technology.
http://news.bbc.co.uk/1/hi/business/7733602.stm
Cheers, Marc
Henley Business SchoolUniversity of Readinguser-1356911063
<h2>Javascript Required</h2> <p>You need to enable Javascript in your browser
to edit pages.</p>
THE CUPS GAME (Jackson, P., The Cups Game NSF Product
Realization Consortium Module Description, Cornell, NY:
Cornell University, 1996)
7/29/2019 Process Design Games
http://slidepdf.com/reader/full/process-design-games 4/16
This activity was designed by Peter Jackson . It illustrates the difference
between push and pull production. It is also effective in demonstrating the
advantages of small lot manufacturing. This activity makes a veryconvincing argument for just-in-time production and has converted many
skeptics.
The unit product for the cups game consists of a four-cup holder,
containing four cups. The cups have lids and straws and are marked with
an adhesive blue dot (see Figure 1). The game requires six participants
while the rest of the class are interested spectators. The first participant is
the supplier and supplies all raw material to the work stations. The next
four participants each work at a workstation. At the first workstation four
cups are placed in the cup holder. At the next station dots are placed on the
cups. At the third lids are placed on the cups and at the fourth station
straws are unwrapped and inserted into the lids. The last participant is the
shipping/quality control station.
Figure 1. Cups game unit product.
7/29/2019 Process Design Games
http://slidepdf.com/reader/full/process-design-games 5/16
This activity is a perfect example that a picture is worth a thousand words.
Students can clearly see the difference between the push and pull systems.
Many become instant believers. We normally play three iterations of the process each lasting about 15 minutes. The first is push, where each
worker produces as much as possible and pushes the work to the next
station. In no time, inventories start building up, table space is consumed,
and last but not least the process deteriorates into a hectic and chaotic
state. Somewhere in the middle of all this, a time piece is introduced to
measure the process turnaround time. The unit often gets buried in
inventories. The activity also calls for the introduction of a quality
problem (red color dots) that often goes unnoticed until quality control atend of the line and numerous red dots later. When the process is stopped,
the following evaluation measures are made: WIP, Space, Time in Process
and Rework. In the discussion that follows the first iteration students
recognize that the excessive WIP at some stations is a problem. Some
students suggest that the bottlenecks in the process are the cause of the
problem and that we should increase the number of workers at some
workstations, add more space, and have quality control at every station.
However if we indicate that the current output rate is adequate to meet our
demand then students recognize that these suggestions are expensive
solutions to the wrong problem.
In our second iteration we demonstrate a pull systems. Kanban space
(adequate for four units) is defined on the tables using tape for each
workstation. Workers are instructed to work a new lot only when their
kanban is empty. Students quickly realize that the rate of output is notaffected by this change (still determined by the longest task time.) In fact,
by eliminating the chaos and clutter workers are likely to work faster. The
measures of performance are greatly improved with this iteration. The
WIP and defects are limited by the kanbans, the time in process is cut in
half, the required table space is down from three to two and the workers
7/29/2019 Process Design Games
http://slidepdf.com/reader/full/process-design-games 6/16
are much happier with some making after class plans. Since WIP and
reworks are reduced the pull system is actually saving money (with no
increase in cost). The most startling point is that by having people work
less hard profits are increased. At this point it is easy to see that the WIP
can be further reduced by reducing the lot size. The third iteration is pullwith a lot size of two. At this point tradeoffs and limitations associated
with reducing lot sizes are discussed.
GOLDRATT'S GAME
This activity is a variation of the game Goldratt described in his "novel",
the Goal (North River Press, 1992, pp. 104-112.). This variation was
described to us by Graham Rand at an IFORS conference in Latvia. It
can be used to illustrate many concepts in production management. We
use it to reinforce the notation that reduction of variation in processes is
more efficient and economical than increasing inventory, or work-in-
progress in this case.
The game simulates a production line with 5 work stations. The product
must pass through each of the 5 work stations in order from 1 to 5. We
use pennies to simulate the process. The potential amount of work
completed at each station in a given time period is a uniform distribution
of 1, 2, 3, 4, 5, and 6. This random potential work is determined each period by the tossing of a die. Hence the average potential amount of
work at each station and thus through the system is 3.5 units per period.
If the game is played for 20 periods for example, one might expect an
average of 70 completed units. However, the actual work completed at
each station is limited by the WIP. The game is played by starting each
7/29/2019 Process Design Games
http://slidepdf.com/reader/full/process-design-games 7/16
station with a WIP of 4. At a signal all stations roll their dice to
determine their potential work. The actual work forwarded to the next
station is of course the minimum of the number on the die and the
number of items in the WIP. We use pennies to represent the item being
produced (No actual work is done at each station as the pennies movealong). The first station's WIP is always replenished to the 4 level. As
the game is played, WIPS begin to vary and eventually in some cases
limit the amount of work done. We set up as many lines as we have
students available. By the end of 20 periods no line will be near the
expected level of 70 finished units. When asked to suggest adjustments
that might allow us to reach the target of 70 units on average, many
students will suggest increasing the WIP. We re-run the game starting
with WIP's of eight rather than four and production does tend to increase but still often below the 70 level. Further discussion usually results in a
suggestion that better results could be obtained by reducing the variation
in the work. The game is played one more time flipping coins to
determine potential production levels with heads resulting in 4 units and
tails 3 units. The average work done is still 3.5 units. Going back to
WIP's of four, this run is the most successful.
A demonstration of theeffectiveness of bucketbrigadesThis a class exercise to simulate order order-picking in a warehouse. It is based on an idea of M. AMIRHOSSEINI of UPS Worldwide Logistics, whom we thank. This exercise willhelp you to• Experience some of the challenges of balancing work when
customer orders are picked progressively.• Understand the principles behind bucket brigades• Compare the performance of bucket brigades to
7/29/2019 Process Design Games
http://slidepdf.com/reader/full/process-design-games 8/16
performance of alternative ways of organizing workers• Train workers to pick by bucket brigade
This simulation takes 60-90 minutes at least. You canusefully devote twice this much time.
Supplies
Figure 1: Order-pickers will pick straws from cups. The pliersand the chopsticks will slow down chosen workers to create a
more realistic range of work velocities.
You will need the following:• About 300 straws. I bought fifteen boxes at about US$0.55
per box, 24 straws per box.• Twenty-four (24) plastic cups, each deep enough to hold
straws. I paid about US$1.45 for a package of 12• One large felt-tip marker• One pair of pliers• One pair of chopsticks• A set of customer orders, which I have prepared for you:◦
Set 1 is the best set to start with because it is thesimplest. Each of 15 locations is selected for thenext order with identical, independent probability.This means that, on average, the work is evenly spread among all locations.
◦ Set 2 is composed of orders with work concentrated
7/29/2019 Process Design Games
http://slidepdf.com/reader/full/process-design-games 9/16
at some locations. (The locations of concentrationdo not change over time and so the distribution of work remains stationary.)
Set up• Using the felt-tip marker, label the plastic cups clearly 1
through 15 and set them up in sequence along a table.Each cup is a storage location from which items will bepicked.
• Put a handful of straws in each cup. These will be the itemsto be picked.
• Place the stack of customer orders to one side of location
(cup) #1.• Pick three students to be order-pickers and give each a cup
in which to carry straws. One student will be allowed topick up straws only with the chopsticks; another only with the pliers; the third may use his fingers. This isintended to ensure that there is a wide distribution inthe work velocities of the order-pickers, as would befound in real-life. (NB: Chopsticks may not slow your
worker down if he is Asian! In that case you will have touse something else, such as a small pair of tweezers.)
Running the simulationI generally start with the simplest style of order-picking, in which a single worker completely picks a single order andthen starts another. I choose one student to time thesimulation (Five minutes is long enough to make interestingobservations but not so long that people get bored.)
For a fair comparison of order-picking methods, it isimportant that everyone follow the same process. I suggestthat each picker initial each pick-line as it is completed; and,after completing an order, stack the pick-list in sequence of completion. Meanwhile, an assigned student recycles thestraws and the cups into which they were picked while I lead
7/29/2019 Process Design Games
http://slidepdf.com/reader/full/process-design-games 10/16
the class in discussion of what we are seeing.In the initial simulation you will see that the workers get
in each other's way; and at the end of the exercise thecustomer orders will have been completed in a sequence
other than that in which they were released. (You can check this by examining the paper pick-lists for the completedorders.) In a real warehouse, this would create work downstream at packing and shipping, where the orders may have to be disentangled if, for example, they had beenreleased in reverse sequence of delivery.
There is also the question of how to measure theproductivity of each worker (for example, have them sign the
customer order after they pick it; but should you count pick lines or orders?). This will generate interesting discussions. You can also interview the workers about their experience of the process.
After the first simulation I ask the class to suggestalternatives to test, with a goal of being most productive.Here are typical suggestions.
Zone-picking
7/29/2019 Process Design Games
http://slidepdf.com/reader/full/process-design-games 11/16
7/29/2019 Process Design Games
http://slidepdf.com/reader/full/process-design-games 12/16
Figure 2: Zone-picking. The flow of work is from left-to-right.The worker in blue is the slowest and you can see work-in-
process (red cups with paper pick-lists) accumulating just to his
left, where his zone begins.
Under zone-picking, each worker is assigned to a zone andhe picks only locations within his assigned zone. This raisesthe obvious question of how to divide the work? And more basically, how do you estimate where the work is and how much of it there is?
The first set of customer orders have been randomly generated so that each location receives about the samenumber of picks. Consequently the appropriate zones, basedon expected or total work, are as follows: Worker 1 is
assigned to pick only from locations 1-5; worker 2 is assignedto pick only from locations 6-10; and worker 3 is assigned topick only from locations 11-15. (Of course, in real life you would have to examine a history of customer orders toidentify the most popular locations and then see where they are located. Some of these challenges are raised by the orderset 2.)
Begin by placing each worker at the beginning of his
zone. The first worker starts picking an order, checking off each pick-line as it is picked. When he has picked everthingfor that order within his zone, he must leave it at the end of his zone for the next worker. If the next worker is notavailable to take the order, it may be placed down on thetable as work-in-process.
Worker 3 will be the one who completes orders. Heshould place each completed order on the table at the end of his zone and go back to get more work at the start of hiszone.
Under zone-picking it can be instructive to put theperson with the chopsticks (normally the slowest picker) inthe middle zone because this gives everyone the chance tosee starvation downstream and build-up of work-in-processupstream.
7/29/2019 Process Design Games
http://slidepdf.com/reader/full/process-design-games 13/16
While workers are picking, have class members measuresuch statistics as throughput rate, work-in-process queued between zones, average cycle time of the orders, etc.
This simulation can be run with each person carrying a
single order at a time. You can also introduce batching by having each person carry two orders at a time. It isinteresting to see the increased congestion and confusionthat results.
Bucket brigades
7/29/2019 Process Design Games
http://slidepdf.com/reader/full/process-design-games 14/16
7/29/2019 Process Design Games
http://slidepdf.com/reader/full/process-design-games 15/16
Figure 3: Bucket brigades. The slowest worker, on the right,with chopsticks, is about to start a new order. The last, fastestworker has "pushed" the other workers back and so expanded
the work she accomplishes.
Under bucket brigades, zones are abolished. Workers arefree to move as far forward or as far back as they must,subject only to the restriction that they must remain in strictsequence of slowest-to-fastest. Therefore, in this simulation,move the person with chopsticks to be the first worker, whostarts orders; move the person with pliers to be the middle worker. The last worker, who completes orders, will be theone using his fingers.
Begin by placing all the workers immediately before
location (cup) 1. On signal, the fastest worker takes acustomer order and begins picking. As soon thereafter aspossible, the second fastest worker takes the next customerorder and begins picking; and then the slowest worker starts.
Here is something for the class to discuss: What shouldthe workers do if the second worker completes an order?
You may need to watch the bucket brigades for the firstfew minutes to make sure that the workers understand it and
perform it correctly.Afterwards After finishing the simulations, you may want to interview the workers in front of the class: What did they think abouteach style of working? Which was harder and why? Whichhad higher throughput? Less work-in-process inventory?
I have run this experiment about ten times now, onstudents and on people from industry, and bucket brigadeshave been 30-100% more productive. Here are the results of a recent class in which we ran 5 minute tests of different ways of organizing the order-pickers.Productivity of some different organizations of the order-pickers.Method Orders Comments
7/29/2019 Process Design Games
http://slidepdf.com/reader/full/process-design-games 16/16