计量型数据MSAppt课件

1、计量性数据MSA简单丈量分析 续 Simple Measurement Study - continued 运用描画性统计， 计算Delta 的规范差Using Descriptive Statistics, calculate the standard deviation of Delta这个规范差被称为丈量规范误差This standard deviation is called the Standard Error for Measurement其主要代表了什么，反复性还是再现性？Which does this primarily represent, Repeatability or

2、Reproducibility?Variable N Mean Median StDev Delta 10 -0.410 -0.400 0.387 简单丈量分析 续 Simple Measurement Study - continued运用上面的规范差，什么是丈量分布的良好估计值Using the standard deviation above, what would be a good estimate of measurement spread?Variable N Mean Median StDev Delta 10 -0.410 -0.400 0.387 假设公差是5 上限下限Su

3、ppose tolerance (upper spec - lower spec) is 5. 准确度和公差的比率如何？What would be the ratio between the precision and the tolerance?简单丈量分析 续 Simple Measurement Study - continued这个比率被称为准确度和公差比率 (P/T). 这个例子中P/T 比率是： This ratio is known as the Precision to Tolerance (P/T) Ratio. For this example the P/T Ratio

4、is:这个可以被解读为：“46的规格公差被丈量系统误差所占用了This is interpreted as: “46% of the specification tolerance is taken up by measurement errorVariable N Mean Median StDev Delta 10 -0.410 -0.400 0.387 丈量才干指数- P/T Measurement Capability Index - P/T准确性和公差比率 Precision to Tolerance Ratio描画有多少百分比的公差是被丈量系统误差占用了Addresses what

5、 percent of the tolerance is taken up by measurement error同时包含了反复性和再现性 Includes both repeatability and reproducibility操作者 x 单位x 实验次数 Operator x Unit x Trial experiment最正确情况 Best case: 10% ； 可以接受 Acceptable: 30%通常以百分比表示Usually expressed as percent留意：6.0规范差代表了99.73% 的丈量系统变差。记住在做丈量系统和以前分析结果的计算时，要经常检查这个

6、值。 这里用的6.0 是AIAG 的工业规范。Note: 6.0 standard deviations accounts for 99.73% of MS variation. Always check the value used when making comparisons between measurement systems or previous analysis calculations. The use of 6.0 is the AIAG industry standard. PTToleranceMS/= 6.0*s准确度和公差比率Precision to Toleran

7、ce RatioProduct ToleranceLSLUSL丈量系统变差measurement system variationP/T = 20%P/T = 100%P/T = 200%丈量才干指数 % GR&R Measurement Capability Index - % GR&R描画有多少总变差比率是由丈量系统误差呵斥的 Addresses what percent of the total variation is taken up by measurement error同时包含了反复性和再现性 Includes both repeatability and reproducib

8、ility操作者 x 单位x 实验次数 Operator x Unit x Trial experiment作为一个目的，我们期望%R&R 30% As a target, look for %R&R 15Select enough samples so that (number of samples) X (number of operators) 15假设不可行，选择测试的次数使得：If not practical or possible, choose number of trials so that:S- 样本数量O- 操作者数量测试次数3 if S x O 15, trials =

9、3测试次数3 到 4if S x O 8, trials = 3 to 4测试次数4 到 5 if S x O 5, trials = 4 to 5测试次数6 到 8 if S x O Quality Tools Gage Study Gage R&R Study (Crossed)Minitab 量具反复性和再现性研讨Minitab - Gage R&R Studies量具的选项：假设有公差，填入此处GAGE OptionsIf There Is A Tolerance For This Part -Put It Here研讨的概要信息General Info On Your Study放入

10、6.0 (AIAG 规范Set to 6.0 (AIAG Standard)Minitab 输出Minitab - OutputExpected ToBe Out of Control%R&R& P/T RatiosGives us the 1st look atdiscriminationGraphical ViewOf ResultsMinitab 输出Minitab - Output细节将在第二周讨论 We will discuss in detail during week 2.Two-Way ANOVA Table With Interaction Source DF SS MS F

11、 PPart 9 2.05871 0.228745 39.7178 0.000Operator 2 0.04800 0.024000 4.1672 0.033Part * Operator 18 0.10367 0.005759 4.4588 0.000Repeatability 30 0.03875 0.001292Total 59 2.24913Minitab 输出Minitab - Output从实务的角度看 我们目前不需求这里的数据From the practical side we dont need anything from here, yet.从统计的角度看 这些原始的统计数据

12、会被套入计算%R&R and %P/T 的公式From the stat side . These are the raw stats that will be going intothe %R&R and %P/T formulasGage R&R %ContributionSource VarComp (of VarComp)Total Gage R&R 0.0044375 10.67 Repeatability 0.0012917 3.10 Reproducibility 0.0031458 7.56 Operator 0.0009120 2.19 Operator*Part 0.002

13、2338 5.37Part-To-Part 0.0371644 89.33Total Variation 0.0416019 100.00Minitab 输出Minitab - Output红色的圆圈重要的比率 Red Circles = Key Ratios%P/T % R&R StudyVar %StudyVar %ToleranceSource StdDev (SD) (6*SD) (%SV) (SV/Toler)Total Gage R&R 0.066615 0.39969 32.66 79.94 Repeatability 0.035940 0.21564 17.62 43.13 R

14、eproducibility 0.056088 0.33653 27.50 67.31 Operator 0.030200 0.18120 14.81 36.24 Operator*Part 0.047263 0.28358 23.17 56.72Part-To-Part 0.192781 1.15668 94.52 231.34Total Variation 0.203965 1.22379 100.00 244.76Number of Distinct Categories = 4我们该做怎样的决议？What decision do we make?Minitab 输出 Minitab -

15、 Output %P/T 最正确：10，可接受：30%Best case: 10% Acceptable: 30% R&R以%R&R 30%为目的As a target, look for %R&R Make Patterned DataSimple Set of Numbersuse Minitab DOE “Create Factorial Design GRRsetup - custom Minitab macroExample MSA: plan an MSA study for 3 Operators, 10 Samples per trial, 2 Trials We want t

16、o create a Minitab file with the following columnsPart or Sample, Operator, Trial, MeasurementGR&R Setup: Factorial Design ApproachPrepare your Measurement System “ExperimentLets use Minitabs experiment generators. Choose StatDOEFactorialCreate Factorial Design. Click the “General full factorial des

17、ign radio button. Leave the “Number of factors at two (2). GR&R Setup: Factorial Design ApproachAfter clicking on Designs, fill in the Factors (Operator, Part) and the Number of Levels for Operator = 3 (three measurement operators)for Part = 10 (ten parts)choose two “replicates Click OK. GR&R Setup:

18、 Factorial Design ApproachClick on the Factors buttonGR&R Setup: Factorial Design ApproachChange Operator Type to “Text.Replace the Operator “Level Values of 1, 2, and 3 with the names of your teams measurement operators. Here we have used Jose, Ann, and Jim. GR&R Setup: Factorial Design ApproachCli

19、ck on the Options buttonGR&R Setup: Factorial Design ApproachBe sure that “Randomize runs and “Store design in worksheet are checked. Always randomize your GR&R experiments! GR&R Setup: Factorial Design ApproachClick OK in the main “Factorial Designs window. GR&R Setup: Factorial Design ApproachChec

20、k the output in your data window. You should now have 60 rows of data. The StdOrder column should be out of numerical order, while the RunOrder column goes from 1 to 60. GR&R Setup: Minitab Macro ApproachA different approach: use a custom Minitab macro.Copy the file GRRsetup.MAC to the Minitab macro directoryC:Program FilesMTBWINMacros(or to the specific Minitab Macro directory for where your PC has Minitab installed)Now we can use Minitabs text command feature to run this macro and