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Teaching DOE

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  • #28855

    Matthews
    Participant

    I am a black belt involved with training green belts and champions, I have continuing problems trying to get an understanding to my pupils on doe. I use the catapult for the experiment and they collect data on all the aplicable settings high and low on each factor. I feel the experiment is very long and doesn’t show real doe capabilities. I wan’t to know if anyone has taught doe using the catapult and how they set up the experiment to show good DOE Capabilities.

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    #72532

    Trent Myer
    Participant

    John
     
    I’m teaching DOE to GB’s next week for my very first time.  If you get any idea’s please post them as I feel I’m going to need all the help I can get.
    If nothing comes through, I have some idea’s of the way to go.  I will gladly pass on my experieces from next weeks course.
     
    Chin up
    Trent

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    #72533

    John Smith
    Participant

    The catapult experiment is a great one but I agree it is too complex and long – especially for green belts.
    We use the paper clip bend strength experiment, using 2 levels each of brand, size, and heat treatment as variables.  Two tests are conducted per level.  The clips are bent repetitively 180 degrees.  The number of bends to failure are counted.
    This has turned out to be a great experiment.  It can be conducted in a reasonable amount of time.  It incorporates an attribute variable (brand).  Often the two brands and sizes have other factors are unique.  We have had experiments that varied with test technique (speed of bending, forcefulness of bending, etc.).  And the analysis is done relatively quickly, and is fairly easy to relate the analysis results with the physical experience. 
    The catapult experiment is my favorite, but it is also technical in nature and takes a long time to conduct.  If the green belt class includes non-technical people, say from HR or sales, they often do not identify with nor enjoy the catapult experiment.  The paper clip experiment seems to fill the bill.
     
     

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    #72534

    Matthews
    Participant

    John,
           Thank you for your reply, I find that the white noise associated with the catapult itself makes it hard to obtain accurate results. Since my last last class I took the oppertunity for myself to see the variation and repeatability of relasing the ball with no changes.
     I found trying my very best to repeat the method of release the variation(White Noise) was sometimes dropping to 12 inches away from the target of 100 inches plus/minus two inches giving me a range of 21 inches.
     I had some success at 75 inches as the target  for the smaller range was producing less variation. I since tried the target of 75 inches with three different individuals with some different results, none two alike. In ideal situations you would instruct your group to firstly test the variation of all the members then opt for the operator with the least variation to make the DOE results more appealing, but thusfore making the experiment even more lenghy.
    Using another method of communicating DOE in this instance I think is the best option because we can never factor out the white noise associated with the catapult tool used, so the process improvement or optimum setting is still in large has too much variation . I have considered opening up the tolerances to absorb some of the white noise but feel the bigger the target the less effect the improvement has in the individuals mind.
    Maybe Trent will be able to shed some light next week after he takes his class through DOE .
    Thanks to you both for your input
    All The Best, John.
     
     

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    #72546

    TCJ
    Member

    You can add another factor to this experiment by evaluating two different brands of paper-clips.

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    #72553

    Peter E. Teti
    Participant

    JOHN,
     
    Call me at (860) 654-4800.  I have an excellent approach using the Catapult that never fails!!!  I will be happy to share with you.
     
    Regards,
     
    Pete Teti

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    #72559

    Trent Myer
    Participant

    Pete
    I am in the same predicament as John.  I’m also in the UK and will probably not be able to phone.
    I would appreciate some specifics in writing.
    Hope you can help
    Trent

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    #72568

    Michael McGrath
    Participant

    PeteI was speaking to John Matthews our Six Sigma Blackbelt, and he said he had contacted you about doing a DOE using the catapult. I am John’s master black belt, working here in Belfast for Bombardier, on this issue, and it would be great to get some advice from yourself. Our problem is basically getting a repeatable process, and there is too much noise, to allow us do a DOE which is really convincing to classes we teach. We reckon if we cannot get good repeatability for a fixed set-up, then any model we derive from our DOE runs will not be very good.If I can phone you tomorrow (Thursday), it would be really good. My telephone number is 011442890462108
    My fax number is 011442890733647
    My e mail is [email protected]
    My address is Bombardier Aerospace, Six Sigma Centre, Airport Road, Belfast BT3 9DZ, N IrelandI’ll phone about 4.00 pm our time, which is probably 11.00 am your time. Look forward to talking to you.Regards
    Michael McGrath

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    #72630

    John C. Sparks
    Participant

    My Review from Amazon.Com: I have used the Milton Bradley JENGA blocks for about 10 years to do industrial training in Design of Experiments (DOE) and basic statistics. The blocks are fantastic! and can be used to illustrate a variety of statistical and DOE principles. JENGA blocks are fun, extremely cheap (compare to a $400.00 minuature catapalt), and durable. My five sets have held up very well throughout a total of 100+ workshops.

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    #72666

    RG
    Participant

    Sounds extremely interesting. John, can you share what you have done in DOE and also in basic statistics. We are in process of setting up some activities for such training and this would help us a lot. Thanks.

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    #72670

    Erik L
    Participant

    John,
    I’ve conducted training for both GBs and BBs and successfully employed the statapault exercise.  My recommendation is to make the exercise flow throughout the conduct of training.  I think that it’s imperative to have an example that can be tied to each tool taught as a practical ‘hands-on’ type breakout exercise.  Even better is to have an example that builds cumulatively (as would their process knowledge from working their respective projects).  The statapault lends itself well to every phase of DMAIC.  Hitting the belt with the catapault for the first time in the DOE sections of the material would be a little overwhelming.  My recommendation would be to introduce it in the define stage and to progress their knowledge of the aspects of the catapault; the CTQs; the various failure modes possible; the various modes of variation; the various impacts of noise; and concepts of robustness.  When DOE rolls around, they’re seasoned vets and then I hit them with the paper clip DOE to get a change of pace.  I know you’ll see better results.
    Regards,
    Erik  

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    #72673

    Harper
    Participant

    Noises are there to discover, not to avoid. Its perfectly normal to have a DOE that cannot repeat itself, which is mostly becoz of the unstableness of underlying noise, or to put it another way, the noises are not true “white noise”, there are factors to be dig out, the closer the noises to true white noise, the better repeatability you have, and vice versa. When you encounter these repeatability problems, best thing you can do is to try to dig some factors from the noises, otherwise you can just tell your pupiles the story about the nature of noises, after all, it’s the mechanism that counts, not the result.

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    #72678

    Mike Carnell
    Participant

    John,
    I am not sure how you have come to the conclusion that it is to long. This is a difficult concept and it is not intuitively obvious. The longest part is typically the instructors time. Of all the training in the SS curriculum Improve is the most tedious because the students do most of it themselves. Maybe your issue is you are bored. Make sure this is their issue not yours.
    There are statapults out there that have been improved. Rather than having primarily interval type setting they now have actual continuous setting for everything except # of rubber bands and type of ball. Try http://www.statapults.com.
    If you want to compare statapults to the old demo of paper helicopters – ther is no comparison.
     
     

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    #72681

    Matthews
    Participant

    I am certain the issue is not boredom, my real issue is the amount of variation that it associated with the catapult itself. I find the repeatability is poor and every five shots there is at least one outliner that has to be extracted.
    Even when I extract the outliners the variation is approx. Seven inches. Once you have completed your doe and then calculated your regression equation at a target of +/- Two inches you are still not producing a statistically stable process to your tolerance. I have thought of opening the process tolerances to absorb the white noise of the catapult. In the students mind the larger the target the smaller influence is on the power of DOE and regression analysis so I am reluctent to take that step.
     What I am considering to do next is to take perhaps six settings for each factor and take 10 shots. I will the calculate the standard deviation for each of the six settings and then take the lowest variation to document the high and low settings for each factor.Doing this will make sure that the least variation is present if the High and low settings are stipulated in the test set up (using the continuous scale associated with the factor) This will give me optimised test conditions and should give better results.
     I am also considering new catapults the brand of catapult could be a key conrtibutor to the amount of variation.
    All The Best,
    John.

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    #72682

    Mike Carnell
    Participant

    A fellow insomniac.
    The statapults with the continuous data modifications are from a guy named Alan Wheat. It sounds like they may fix your issue.

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    #72692

    Trent Myer
    Participant

    John
    Jenga blocks sound interesting.  Can you elaborate more?  Its now fri afternoon and the brain is slowing quite quickly.  What do use for the factors?  The levels of interest?  What is the effect?   How big are the groups for training?  Do the figures work in Minitab?
    Sorry if my imagination is’nt working but its been a long week.
    Cheers
    Trent

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    #72704

    Erik L
    Participant

    John,
    If the issue is variation are you analyzing the data so that you’re creating the Y=F(x) and S=g(x)?  That way, you can tell which factors are driving the variation that you’re seeing.  Remember the basics of DOE.  What is the objective of the design?  Highest performance?  Minimal variance in the response?  Both?  That’ll guide you to the right design.  The benefit of the DOE is seen from the fact that they have taken a minimum of runs to analyze performance, and based on an equation derived from their DOE, they can hit a target anywhere in their experimental space.
    Regards,
    Erik

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    #72715

    Jim Johnson
    Participant

    Hello.  We use a paper helicopter as the basis for the DOE instruction.  There are three variables:  Wing Length, Body Length and Body Width.  A variation also can include using or not using a paper clip.  This works pretty well for Green Belt level understanding and doesn’t take nearly as long as the catapult experiments typically do.
    I hope that this helps.
    Jim Johnson.

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    #72751

    Matthews
    Participant

    Erik,
           I am now analysing the sources of variation and in some cases it is very visual such as the movement seen in the start angle stop, when you apply pressure. I have now got a few people involved and we are looking to make improvements to the catapult after we brainstorm the issues.
     I plan on doing some paired t comparisons with different design changes, one design change recomended was the cup in where the ball or projectile actually seats, So I am going to use the methodology and apply it to the catapult itself.
     I can also use the findings to show students a catapult before and one afterwards and allow them to measure the variation of the two and physically see to outcome of a six sigma project.
    The great thing about the Six Sigma Methodology is you can apply it in almost any circumstance and achieve great results, Thanks for all the responses I will post my findings after I improve the current process.
    All The Best,
    John.

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    #72755

    Keith Boyle
    Participant

    The paper helicopter is very simple, fast and involves all the particpants in the understanding of DoE. It has controlled and uncontrolled variables and is available with standard office supplies – ie, paper, paperclips, etc. Once I used the helicopter after using the catapult I have never gone back.
    email me if you need further info.
    [email protected]
    http://www.qprs.com
     

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    #72756

    Jeff Ayland
    Participant

    John,
    I dont have a blackbelt certificate. But i have taught DOE using the Catapult. The catapult can be a long way into understanding DOE. I usually do some building blocks before going to the catapult. Start with ping pong balls from say 4 manufacturers and drop them from a metre ruler, record bounce time across the 4 makes. Use this with 1 way anova to show some of the basic fundamentals of DOE. Then i move on to basic helicopters made from paper, vary the wing width and length, run a 2 factor Anova. Then the next session move on to the catapult full up. After these building blocks are in place the DOE comes easier. I had a good teacher, a chap called Tony Chirico at Moog Inc out of Buffalo NY. The key is breaking the lecture down into key stages, i would do the course over 4 weeks, one day a week, 4 days in total, usually wednesdays. At the end of week 4 DOE is usually understood by all attendees.
    Cheers, Jeff.

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    #72757

    lin
    Participant

    Here is a link to an online catapult that is a lot of fun.  I am making it accessible through the end of the month to get comment for improvement.  We use these type of simulations as part of our online Six Sigma courses, and would appreciate feedback from others involved in DOE instruction.
    http://www.moresteam.com/trebuchet.cfm
    Make sure to turn up your sound to get the full effect.
     
     

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    #72759

    Bobby
    Participant

    Just remembered we were once trained on DOE using bubbles.  It was a blind DOE, the trainers brought in 2 different solutions (1 regular bubbles, like from KM/WM, 1 containing acetone), 2 different wands (1 from bubbles, 1 made of pipe cleaner), and used different people as 3rd variable.
    It was a lot of fun to see 30+ adults blowing bubbles.
    Some variables that we experienced:
    large conference room (lots of wind currents), cross contamination of bubbles from 1 group to another, difficult to count all the bubbles in some instances
    One group went to a phone booth outside of the training room and blew bubbles down onto a piece of paper then counted the rings left from the bubbles.
    Then we had a post mortem on the whole process.

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    #72762

    Schuette
    Participant

    I have read everyone’s messages and agree that teaching DOE does have room for simplicity and knowledge transference. It is far from boring. I find that it is too equipment dependent. I really would like to find an exercise which can be carried into the field without a shipping trailer, which is understabdable and most importantly easily transferable to more practical on the job applications. Granted the instructor plays a major role in making the tie, but someone must have developed a better DOE training tool. Can someone tell us more about the paperclip, paper plane or other desktop exercises.

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    #72764

    Shree Phadnis
    Member

    Dear Friends,
    I am attaching a PDF file of the entire Paper helicopter experiment.I am e mailing the same to isix sigma for the benifit of all.
     
    Shree Phadnis

    Download: Teaching Design of Experiment (DOE) – Helicopter Example
    Viewing Tip: Usually, you can click on a link to view the document — it may open within your browser using the application (in this case Adobe Acrobat). If you are having difficulty, try right clicking the link and selecting “Save Target As…” or “Save As…” to save it to your computer harddrive.Virus Note: All files are scanned prior to uploading to iSixSigma. No prevention program is entirely safe. FOR YOUR OWN SAFETY, PLEASE:1) Re-scan downloaded files using your personal virus checker before using it.2) NEVER, EVER run compiled files (.exe’s, .ocx’s, .dll’s etc.). If you don’t have a virus scanner, you can get one at many places on the net including McAfee.com.

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    #72766

    Swaggerty
    Participant

    I’ve seen and used a number of DOE teaching props, like catapults, paper planes, and the like.  My favorite portable physical props are paper helicopters.  Typical factors are things like wing length, body length, body width, # of weights (paper clips).  You can also use different paper thickness.  Measure time of flight for the response.  This same tool can also be used for GR&R, process mapping, C&E matrix, FMEA, etc.  Another approach is to use a computer simulated process.  You can make your own in Excel, or use a commercial package.  The advantage of this is that you can tailor the process behavior to what you want, but it doesn’t have a much hands-on feel to it.

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    #72774

    RR Kunes
    Member

    The catapult is fun and usually enjoyable.
    Another quicker one is to use Bayer aspirin and regular aspirin to determine is which solution Soda or H20 and stirring or not stirring.
    Which painkiller dissolves faster.
     
    In the catapult you shoud have only three or four factors. To reduce the time reduce the factors.
     

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    #72776

    Mendoza
    Member

    I think that the only thing you need is, How to plan a DOE? no matters what process you are working on, this must give you what to do and how to do it.

    I use to let the class to decide most of the exercise. OK, sometime they miss the objective, but in real life is what happen and in the class is a excelent opportunity to see this and talk about it. Normally end it up with “planning is the most important part of DOEs”.
    There are another big issue, about any kind of excercise to teach DOEs, the measurement system. I normally asked to the class to include before the DOE a Gage R&R to validate the measurement system. Well, if they do not have an acceptable system, they must improve it before running the DOE.

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    #72777

    Larry Goldman
    Participant

    John Matthews -If you would like a good example of a spreadsheet model for catapult simulation, I suggest you visit
    http://www.crystalball.com/models/model_index.html.
    The Six Sigma section of the models page includes
    a catapult model contributed by John O’Neill Jr. of Compass Quality Management. he uses the model for Six Sigma training and has included a description of how he uses and simulates the model for DOE.Larry Goldman
    Decisioneering

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    #72778

    Mendoza
    Member

    Shree,
    I could not see any attachment. Could you please try again to attach you pdf? Thanks,

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    #72803

    Kevin gong
    Participant

    Dear, Would you pls share me your experiment addressed as below?
    [email protected]
    Thanks
    Kevin Gong
     

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    #72834

    Darryl Boyd
    Participant

    John,
    To a degree, I agree with Mike Carnell.  The tool cannot be the problem.  The prop used to teach the tool is just a prop, so it will not be perfect/exact.  You, first and foremost, must be comfortable with the tool. When you are comfortable, use another prop that is more fitting to you.  There are an endless number of examples:  marbles, golf putting, helicopter, miniature bowling, etc.

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    #72946

    Elias
    Participant

    John
    Can you please explain me how does the JENGA blocks training for DOE is made?
    Thanks

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    #72948

    Manee
    Participant

    After learning DOE, I found a good tool rdExpert to analyze experiments
    Manee

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    #73139

    Dale Beach
    Participant

    We did all of our sigma training using the catapult. The first thing we did was to reduce the noise by C & E , C/N/X, & SOP. We went from 31 inches of variation between four operators to under 4 inches. Then we did the DOEs. This is why they say most 90 % of the problems can be solved without DOE or advances stats and why some DOEs seem not to be reproducable. If you haven’t standardized your process to drive out the noise then you may not get much from your DOEs. Try using the catapult to teach variation reduction and work standardization to your greenbelts before you go into DOEs. It really fits together real well.

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    #77309

    ellzey
    Member

    would you please email me a copy of teaching the doe I am not allowed to download due to security reasons at my facility but I would be ever so grateful.
    best regards,
    strugggling hahaha

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    #77311

    Türker
    Member

    I am trying to understend what is going on

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    #89220

    Mike Fields
    Participant

    Our company offers an instruction guide that addresses experiments in DOE as well as other methods.  The guide is specifically written for instructors and each experiment is broken down into facilitator and student sections.  The facilitator sections have all the data and the questions to pose to the students.

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    #89244

    Mike Fields
    Participant

    Throw out a 6″ paper plate to a random location and ask the class if they know how to set up the Statapult to hit this target.  Probably not.  How many trial shots would be needed? Probably 4 or 5.  Have a volunteer do this.  Now, what if the customer moves the target?  Would you have gained enough knowledge from the previous trail shots to now hit the new target? Probably not.  Pose this: If you could hit the target the first time, would that be of some value?  Do customers ever change their specifications?
    Make a bet with the class.  “If you give me 4 practice shots, I’ll bet I can hit any spot on the floor with the very first shot.”  You will gain more than shooting skills, you will gain something Deming called “profound knowledge”.
    Draw a test matrix on a flip chart:
    pull bk angle    stop pin        shot 1     shot 2     avg
    160                 

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    #89258

    Mike Fields
    Participant

    Sorry, ISP went down.  To continue:
    Throw out a 6″ paper plate to a random location and ask the class if they know how to set up the Statapult to hit this target.  Probably not.  How many trial shots would be needed? Probably 4 or 5.  Have a volunteer do this.  Now, what if the customer moves the target?  Would you have gained enough knowledge from the previous trail shots to now hit the new target? Probably not.  Pose this: If you could hit the target the first time, would that be of some value?  Do customers ever change their specifications?
    Make a bet with the class.  “If you give me 4 practice shots, I’ll bet I can hit any spot on the floor with the very first shot.”  You will gain more than shooting skills, you will gain something Deming called “profound knowledge”.
    Draw a test matrix on a flip chart:
    here are some actual distances plotted:
    pull bk angle    stop pin        shot 1     shot 2     avg
    160                     5               89          89.5      89.3
    160                     3             126.5     127.5     127.0
    180                     5              118       117.5     117.8
    180                     3             173.5     171.75   172.6
    Notice that I changed just a bit, I took four shots but two repetitions of each run.  Why might this be an advantage?  The additional repetitions allow me to reduce the effects of random errror on my results.  I can also use this data to calculate the standard deviation of each run.  I can use these standard deviations to model the shot distance as a function of pull back and stop pin setting.  We can determine if some process settings have a big influence over the standard deviation.
    Create a simple coded matrix of the variables
    pull bk angle   stop pin
    160 = (-)         5 = (-)
    160 = (-)         3 = (+)
    180 = (+)        5 = (-)
    180 = (+)        3 = (+)
    To aid in understanding, make the minus setting the one that results in a shorter shot.  Next show how to build a regression equation.  Begin with the calculation of the coefficients for the equation.  Here is a step by step procedure for calculating the coefficient of the A term:
                  coded levels                                 distance
    pull bk angle (A)    stop pin (B)    A*B          avg
           –                          –                  +            89.3
           –                          +                  –          127.0
           +                         –                   –          117.8
           +                         +                  +          172.6
    —————————————————                                                       Y =      126.7
                     (117.8 + 172.6)
    avg of (+) = —————-   =  145.1875   
                                 2
                         (89.3 + 127)
    avg of (-) = —————-    =   108.125
                                 2
    avg + = 145.1857
    avg – =  108.1250
    Delta=     37.0626
    Delta/2 =  18.53125
    This process works because we have a two level design and we have standardized the levels.  The students can see how this is done if the following diagram is provided:
                                       |  distance
                                       | /    145
                                      /|        |
                                  /    |        |
                       108  /       |        |
    —————–|——|—–|——
                            -1       0      +1
                           coded levels of A
                                  RISE     (145-108)
               SLOPE  =  ——- = ———  = 18
                                  RUN           2
                  coded levels                                 distance
    pull bk angle (A)    stop pin (B)    A*B          avg
           –                          –                  +            89.3
           –                          +                  –          127.0
           +                         –                   –          117.8
           +                         +                  +          172.6
    —————————————————                                                       Y =      126.7
    avg + = 145.1857    |   149.8     |  130.9375 |
    avg –  =  108.1250   |   103.5     |  122.4       |
    Delta  =     37.0626  |  46.3125  |  8.5625     |
    Delta/2 =  18.53125 | 23.15625 |  4.28125   |
    We can therefore construct the model in this fashion:
                              =  delta A       delta B     delta AB
    Shot Distance = Y+——-A+———B+——–AB
                                       2               2               2
    Shot Distance = (126.7)+(18.5)A+(23.1)B+(4.3)AB
    We can simply add the extra terms one after another because the test matrix was orthogonal.
    We have an equation.  The plate can be placed at any random location and the equation solved for the set-up parameters.  There is one equation and two unknowns, so many solutions exist, but we can pick one.
    The center point is where the input parameters are set to their mid-points.  The mid-points have been coded a”0″.  Let’s substitute this value into the equation for A and B, which results in the predicted distance.
    126 inches.
    Place the plate at this distance.  Insure your reputation is on the line if the ball misses the plate.  Build tension in the classroom.  If you carefully follow your SOP’s and have a consistent pull/release mechanizism, you will amaze the class with your powers.  Before your load and shoot, remind the class of the lessons learned of the essential elements of DOE:
    – An orthogonal array
    – Coding the inputs
    – Building the model
    – Confirming the model’s validity
    Site the plate, load and shoot. Even you will be amazed the first time you do this!
    Good luck.

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    #89428

    Poe
    Participant

    Mike,
    Thanks for sharing this experiment model. I was wondering if you happen to know where I can get a step-by-step guide of the Catapult excersise and other DOE with their explanation as I am determined to continue exploring six sigma.
    Thanks

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    #89429

    Mike Fields
    Participant

    Juan, many sources exist on this site and others. e-mail me for some specifics. [email protected]
    Mike

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    #112157

    Jararatnam
    Member

    Mike, you listed you had information on DOE exercises, please let me know how or where I can get more information on this. thank you, RW

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    #131083

    George Dyson
    Participant

    Does the Crystal Ball catapult simulation still exist?
    thanks,
    George Dyson
     

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    #131086

    Larry Goldman
    Participant

    Dear George,
     
    It does indeed exist: http://www.crystalball.com/models/sixsigma.html#model1. You may also be interested in downloading Crystal Ball 7.2, which has several DoE models other than the catapult.
    Larry

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    #146135

    Joaqcam
    Participant

    Thank you so much, your reference is very valuable.
    Joaquin

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    #146160

    doe
    Participant

    Huh a similar DOE with a step-by-step guide on conducting DOE.
    Follow the link at http://www.ict-m.com/ictm/public/Publications/Projects/DOE/EngApproach/default.aspx
    The excel sheet within might help you a bit.
    Have fun.

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    #170333

    Rachel Zhao
    Participant

    Hi, Mike
       i don’t know if you are still in the original company, now i want you give a favor about the DOE kits. Our company ever belongs to ITT China TianJin and now was bought by another EuroAmerican company last year. We have a lot of Black Belt resource and also want to get more in the future. This year, we will continue to organize BB training in China and want to buy DOE training kits. Do you have some good advice on it? hope you can answer me as soon as possible.

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    #170362

    Bower Chiel
    Participant

    Hi RachelAre you familiar with the Box helicopter experiments? I’ve used them to teach DoE. The free article at http://www.asq.org/qic/display-item/index.pl?item=20773
    describes how to construct them.Best WishesBower Chiel

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    #172125

    mfields
    Participant

    Rachel, e-mail me at [email protected] for more information.  Regards,  Mike

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    #172126

    mfields
    Participant

    Here is the information you requested.
    http://www.ncmrcompany.com/TG1+%2D+Learning+Statistics+Using+the+Catapult.html has 16 or so experiments specifically for the catapult. Mike

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