Study on the Model of Analysis and Control of Parallel Measurement Systems

Parallel measurement systems are widely used in modern manufacturing systems. It is not feasible to analyze this kind of measurement systems with the traditional MSA (Measurement System Analysis) method. Thus two measurement analysis models for the parallel measurement systems are put forward. One is for the analysis of the variation between the instruments and the other is for the analysis of the time variation of one instrument. In the first model, the different measurement instruments are seen as the source of variation. With this MSA model, the GR&R (Gauge Repeatability and Reproducibility) of the parallel measurement system can be calculated. If the GR&R is less than 15 percent, the instruments of the parallel measurement systems can be seen as one. And in the second model, the time is seen as the source of variation and the stability of an instrument is analyzed. Based on the result of MSA, a SPC (Statistical process control) model for the parallel measurement systems is put forward and the variation of the products and different instruments can be controlled at the same time. At last, a case in mobile telephone assembly is studied.