Measurement Systems Analysis (MSA) [WORK]
A measurement systems analysis (MSA) is a thorough assessment of a measurement process, and typically includes a specially designed experiment that seeks to identify the components of variation in that measurement process. Just as processes that produce a product may vary, the process of obtaining measurements and data may also have variation and produce incorrect results. A measurement systems analysis evaluates the test method, measuring instruments, and the entire process of obtaining measurements to ensure the integrity of data used for analysis (usually quality analysis) and to understand the implications of measurement error for decisions made about a product or process. Proper measurement system analysis is critical for producing a consistent product in manufacturing and when left uncontrolled can result in a drift of key parameters and unusable final products. MSA is also an important element of Six Sigma methodology and of other quality management systems. MSA analyzes the collection of equipment, operations, procedures, software and personnel that affects the assignment of a number to a measurement characteristic.
Measurement Systems Analysis (MSA)
Common tools and techniques of measurement systems analysis include: calibration studies, fixed effect ANOVA, components of variance, attribute gage study, gage R&R, ANOVA gage R&R, and destructive testing analysis.The tool selected is usually determined by characteristics of the measurement system itself.An introduction to MSA can be found in chapter 8 of Doug Montgomery's Quality Control book.These tools and techniques are also described in the books by Donald Wheelerand Kim Niles.Advanced procedures for designing MSA studies can be found in Burdick et al.
The Automotive Industry Action Group (AIAG),a non-profit association of automotive companies,has documented a recommended measurement systems analysis procedure in their MSA manual.This book is part of a series of inter-related manuals the AIAG controls and publishes,including:
Measurement System Analysis, or MSA, is a formal statistical study that determines whether your measurement systems, whether they be measuring devices or people, are capable of providing reliable data so that you can make the best possible data-driven decisions. The statistical study used for continuous data is called a Gage R&R study, and the tool used for discrete data is called an Attribute Agreement Analysis.
The results showed no clear correlation between anything - in spite of years of anecdotal evidence to the contrary! In fact, the underlying strong correlation between variables was confounded by excessive error in the measurement system. When the measurement systems were analyzed, many were found to exhibit error variation 2-3 times wider than the actual process spread. Measurements that were being used to control processes were often leading to adjustments that actually increased variation! People were doing their best, making things worse.
There are other methods that can be used to evaluate measurement systems. Most statistical software packages, including Minitab, support ANOVA methods. You can download free trial versions of several software packages through the Toolbox.
Measurement Systems Analysis is a key step to any process improvement effort. By understanding existing measurement systems a team can better understand the data provided by those systems and make better business decisions.
Measurement Systems Analysis (MSA) connects to measurement data that is used in nearly every manufacturing process. As the quality of the data improves, the quality of decisions improves. This guide will help you assess the quality of your measurement systems, providing a basis for recognizing where improvements can be made. The result is knowledge that can be used to improve your measurement process, in turn improving repeatable product quality.
Improve your understanding of the integration of statistical process control (SPC) and measurement systems analysis (MSA) into IATF 16949 and discover how to develop a higher quality process control system by selecting and applying the appropriate statistical tools.
This guide will help you assess the quality of your measurement systems, providing a basis for recognizing where improvements can be made. The result is knowledge that can be used to improve your measurement process, in turn improving repeatable product quality.
The first objective of the MSA is to validate the measurement system used to collect the data before moving onto the ANALYZE phase and running statistical tests. Within this analysis, you will quantify both the:
This module provides additional insight in measurement systems analysis. This is critical component of the MEASURE process that is often overlooked or skipped and could lead to incorrect conclusions and rework in the later stages of the DMAIC journey.
Measurement System Analysis (MSA) is used to determine the suitability of a measurement system for use. It is crucial to have a well-functioning measurement system so that the data collected is accurate and precise. There are many factors to consider when conducting a measurement system analysis. This paper will discuss the importance of Measurement System Analysis and how to go about completing one.
The first thing a measurement system analysis seeks to define is whether the correct measurement is being used for the measurement system. Does the approach make sense given all the potential factors? This is followed quickly by the assessment of the measuring device. Many times, measuring tools such as gages and fixtures wear down or break, rendering them less effective. The MSA will determine if a measuring tool or device needs to be calibrated, replaced, or updated.
This guide presents terminology, concepts, and selected methods and formulas useful for measurement systems analysis (MSA). Measurement systems analysis may be broadly described as a body of theory and methodology that applies to the non-destructive measurement of the physical properties of manufactured objects. This guide presents selected concepts and methods useful for describing and understanding the measurement process. This guide is not intended to be a comprehensive survey of this topic.
Measurement statistical analysis (MSA) is the practice of using statistical tools such as a gage R&R (repeatability and reproducibility) study to determine if a measurement system is capable of precise measurement. In addition, MSA determines the amount of error derived from the measurement process itself.
The purpose of MSA is to assure that a selected measurement system delivers reliable results with repeatability and reproducibility. When conducting a PPAP, all measurement systems are identified in the control plan. A gage R&R is performed for each one of these systems to check for precision.
(Note: all the previous publications in the measurement systems analysis category are listed on the right-hand side. Select "Return to Categories" to go to the page with all publications sorted by category. Select this link for information on the SPC for Excel software.)
That's where measurement systems analysis, or MSA, comes in. MSA is a collection of methods you can use to assess your ability to collect trustworthy, reliable data--the kind of data you want to analyze.
MSA helps determine how much of the overall variation found in your data is due to variation in your measurement system itself. Factors that might affect the measurement system can include data collection procedures, gages, and other test equipment, not to mention the individuals who are taking the measurements. It's just good sense to evaluate your measurement system before control charting, capability analysis, or any another analysis: it proves that your measurement system is accurate and precise, and your data are trustworthy.
If your measurement system is working perfectly, wonderful: you won't have problems with accuracy or precision. But most systems can have one or both of these problems, and even if the system was working great a few months ago, something may have changed in the interim. The device that worked great last month might have slipped out of calibration, either through accident or just plain wear and tear. You might have a gage that measures the same part consistently (it has precision), but that measurement is wrong. Or the device might take measurements that are close to the actual value (it has accuracy), but show a lot of variation between multiple measurements of the same part. And you might have a device that records both inaccurate and widely variant measurements.
And thus far we're just considering the device being used to take the measurement. If your measurements are being done and/or recorded by human beings, with all their innate potential for error and variation, and you can quickly see where doing data analysis without doing an MSA first creates boundless opportunities for disaster.
We are living in a data-driven society, where data are produced and required for analysis in every scenario. It can be either in manufacturing or service industries. Some of the examples are automobiles, pharmaceuticals, garment, healthcare, airlines, banks, consulting firms, etc. MSA helps us to find variation due to measurement system itself and guide us to improve the system for measurement.
Measurement system analysis is a method to determine whether the measurement system is acceptable or not. It helps us to detect the amount of variation exists within a measurement system. Use measurement system analyses to determine the amount of total variation that is from the measurement system and to analyses to evaluate the consistency and accuracy of operators.
Data are collected for some sort of measurement system. A Measurement System is a collection of measurement devices, measurement procedures and operators that are used to obtain a measurement. Before collecting data we should know which type of data we are dealing with. So it would be easier for us to use the rightful method for analysis. 041b061a72