Every manufacturing company collects copious amounts of data on systems and processes daily. This data then informs decisions across all areas of the company, including hiring, equipment needs, and even environmental elements. With so many critical factors at stake, it’s imperative that data collection is reliable. The only way to know this is to use a measurement system.
Measurement systems are a group of related measures that help companies quantify various characteristics of a process to assess the characteristic’s accuracy. While many companies are quick to put measurement systems in place, many struggle to keep up with them, rendering them obsolete after too many years of neglect.
This begs the question: how does a company know that the collected data is reliable?
Enter measurement system analysis.
Understand the phases of Six Sigma like define, measure, analyze, improve and control (DMAIC) with the Lean Six Sigma Green Belt Certification.
What Is Measurement System Analysis?
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.
MSA is a process used to evaluate the suitability of a measuring system for use. A measuring system can be any combination of a transducer, signal conditioner, display, recorder, or data acquisition system used to obtain a measurement. A measuring system is suitable if it meets the required technical performance specifications. MSA is used to identify and quantify the sources of variation in a measuring system.
Measurement Systems Analysis Fundamentals
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.
The measurement system analysis will also assess the personnel’s ability to effectively execute the measurement system instructions and any environmental factors that might affect the process. Any variations in the operation process could result in skewed results, potentially leading to flawed products. The MSA’s goal is to identify these variations and prevent this from happening.
Finally, the measurement system analysis will calculate all this variation to determine if the current measurement system needs an overhaul. While there are many tools and techniques that can be used to complete an MSA, such as calibration studies or destructive testing analyses, we’re going to explore the procedure for a Gage R&R.
Procedure of MSA: Gage R&R Study
A software program at a thermal control company is programmed to cut a piece of metal to 12 inches. This piece of metal will eventually become a housing for a thermal control, so it’s imperative that the first piece of metal measure accurately each time. As part of this company’s quality control, they’ve created a measurement system in which line operators randomly pull pieces of metal off the line to measure them with a digital length gauge. This helps to ensure the machine’s ability to accurately cut the metal.
But how do these operators know that they can rely on their digital length gauge? In this case, the company decides to perform a Gage Repeatability and Reproducibility Study (Gage R&R).
Step 1: Determine Type of Data Collection
In this case, the manufacturing company wants to know if there is any variation in each piece of metal’s measurements. This is called variable data, which means the potential exists to have measurements that vary between samples.
Step 2: Sample Collection and Operator Selection
The next step is to collect a random sampling of the sheet metal during any given production run. It’s important to obtain at least 10 samples. Once the samples have been randomly chosen, recruit three operators who routinely complete the measurement system process to participate in the study. Before the study begins, the sampled sheet metal pieces are labeled with their appropriate lengths without the operators being aware of these labels.
Step 3: Measurement Process
For this example, the random sampling includes 10 samples of sheet metal casings. Each operator will measure the sample casings and record their data. Each operator will measure the same random sampling of ten sheet metal casings three times, for a total of thirty measurements. Lastly, the study organizer will rearrange the sample set between each operator to remove any potential bias.
Step 4: Calculations
Once the operators have completed all three rounds of measurement, the study organizer will compare each set of measurements to three evaluation areas. First, the organizer will compare each measurement to a master value. Second, the organizer will compare each operator’s measurements across all three rounds, essentially comparing each operator to themselves. This is called ‘within’ variation. Last, the organizer will compare each operator’s measurements to the other appraiser’s measurements. This is called ‘among’ variation.
When the operator compares each variation measure, they’re looking for any potential measurement error. If the ‘within’ variation varies greatly, there is likely inconsistency in the process the operator uses to measure the sheet metal casings. If the ‘among’ variation varies greatly, there is likely inconsistency in how each operator was trained to measure the sheet metal casings.
Once the organizer has compared the variation measures, they’ll begin the calculation process to identify the following information:
- Mean readings for each operator
- Standard deviation for each operator
- Differences between each operator’s average and standard deviation
Here, the organizer is looking at the distribution of the data. If all the numbers stack close to the desired mean, in this case, twelve inches, that means the operator, the measurement process, and the measurement tools are working properly. This is called accuracy and usually means everything is right on track.
Repeatability and Reproducibility
All these calculations help determine the repeatability and reproducibility, or the R&R portion of the study. Repeatability will tell you the effectiveness of the tool used for measurement purposes. Reproducibility will tell you how much variation existed between operators, indicating whether there is a need for updated training or process management.
This R&R percentage will determine whether the gage is acceptable for continued use. If the score falls below 10 percent, the measurement system continues to operate as an acceptable system. If it falls above 30 percent, action is required to improve the measurement system to bring it to a Gage R&R percentage under 10 percent. A Gage R&R percentage between 10 and 30 percent can sometimes be acceptable, depending on how other factors are considered in the measurement process.
MSA in Quality Management
It’s not enough to have a measurement system if it’s never properly analyzed and calibrated. Without a strong MSA, the quality of products will suffer, harming customer loyalty. When a robust MSA in the six sigma program is properly utilized, problems are easier to detect, and waste is easier to eliminate.
MSA is a critical component in quality management and six sigma because repeatable and reproducible data prevents and reduces waste. A useful MSA will help companies determine ways to adjust and improve both measuring tools and measuring processes.
Measurement System Error
Measurement System Error is a type of statistical error that occurs when the measuring device used to obtain a measurement is inaccurate. This can happen for various reasons, but it is often because the measuring device needs to be properly calibrated or the person using it needs to be adequately trained. Measurement System Error can also occur when the measuring device is not properly maintained or when the measurement conditions are not ideal.
Any measurements that are taken during the research will have some inherent errors. This error can be due to many factors, and the goal is to design a system to account for and correct this error. There are many error types, and your paper will likely fall into one or more of these categories: systematic, random, or gross errors. Systematic errors are caused by a flaw in the design of the measurement system and can often be corrected if the defect is known.
Location (Average Measurement Value vs. Actual Value)
The Average Measurement Value (AMV) and Actual Measurement Value (Actual Value) need to be compared to evaluate the accuracy of the water level sensor. The sensor is located inside the vent box at the top of the well, and the sensor measures the water level concerning the height of the water in the well from the ground surface. An important factor affecting the sensor's accuracy is the water's height in the well.
A study by the University of Miami that looked at data from the National Oceanic and Atmospheric Administration (NOAA) showed that the average global sea level had risen about 3.2 millimeters per year over the past 25 years. The study also showed that in recent years, the rate of sea level rise has been accelerating. The research found that the global sea level has risen about 14 centimeters (about 5.5 inches) since 1993. The study's lead author, Stefan Rahmstorf, said that the findings are consistent with what scientists have seen in other studies.
Variation (Spread of Measurement Values - Precision):
Variation is a measure of the spread of measurement values in a set. The more significant the variation, the less precise the data.
Variation is a measure of the spread of measurement values in a set, and the greater the variation, the less precise the data. Precision is a measure of how close together two measurements are and how likely it is for them to be correct. Precision is the number of digits in the measurement value and measures the difference between values close to each other.
What Are the Types of Measurement System Analysis?
There are three main measurement system analysis types: attribute agreement, variable agreement, and stability.
- Attribute agreement is a statistical method that assesses the consistency of ratings between two or more raters.
- Variable agreement evaluates the agreement between two or more measurement systems that generate quantitative data.
- Stability assesses the consistency of measurements over time.
How to Analyze Data in Attribute Agreement Analysis?
Agreement Analysis is used in survey research to analyze responses to multiple questions. The purpose of Agreement Analysis is to determine whether respondents are consistent in their responses to questions. Agreement Analysis can determine whether respondents are consistent in their responses to questions about a single topic or whether they are consistent in their responses to multiple topics. Agreement Analysis is a useful tool for survey researchers because it can identify problems with questionnaire design, evaluate data quality, and improve estimates' accuracy.
This tool can be used to find patterns in data and to make predictions about future events. Attribute Agreement Analysis can be used to analyze data in various ways, including finding patterns in data, making predictions about future events, and understanding the relationships between variables.
When to Use Measurement System Analysis?
Measurement System Analysis is a statistical tool that can be used to assess data quality. This tool can be used to determine measurements' accuracy and identify sources of error. Measurement System Analysis can assess data quality from various sources, including surveys, experiments, and observational studies.
What Are the Acceptance Criteria for Measurement System Analysis?
There are three main acceptance criteria for measurement system analysis: repeatability, reproducibility, and stability.
- Repeatability is the degree to which repeated measurements of the same quantity agree.
- Reproducibility is the degree to which measurements of the same quantity made by different observers agree.
- Stability is the degree to which measurements of the same quantity made at different times agree with each other.
Where Can We Apply Measurement System Analysis?
Measurement System Analysis can be used in a variety of settings.
- One set is in research and development, where it can be used to assess the suitability of a new Measurement System for a particular purpose.
- Another setting is in manufacturing, where it can be used to assess the suitability of a Measurement System for use in quality control.
- Finally, Measurement System Analysis can also be used in service industries, where it can be used to assess the suitability of a Measurement System for use in customer satisfaction surveys.
Why Is Measurement System Analysis Important?
Measurement System Analysis is important because it can improve the quality of measurements. In addition, MSA can be used to study the effects of Measurement Error on process capability. Finally, MSA can be used to improve the accuracy of measurements.
What Kind of Organisations can Benefit From MSA?
Organizations can benefit from MSA in many ways. One way is that it increases the organization's productivity. MSA has the potential to increase the organization’s productivity by around 40%. This is because there are fewer mistakes and typos, which means less time spent on editing and more time spent on creating content.
Another way that organizations can benefit from MSA is that it will help them to meet their KPIs. By using AI assistants, organizations have a higher chance of meeting their KPIs as they will be able to create more content at a faster pace.
Lastly, organizations can benefit from MSA because it will help them to save money. AI assistants are cheaper than human copywriters and this means that companies don't have to spend as much money on hiring writers or buying expensive software for writing purposes.
Of course, the measure phase of a project is just one of many phases any given project goes through. In Simplilearn’s Lean Six Sigma Green Belt Certification, you will learn all of the intricacies that go into the Measure Phase as well as the other four phases that make up a project. This certification course has options for self-paced learning and blended learning, giving users the ability to choose the learning model that works best.
Having an intimate understanding of MSA in quality management or MSA in six sigma is fundamental for anyone who works in quality control or is simply looking for ways to improve an organization’s quality or process.