McLinn, James A. (1989, ASQC) McLinn, Dale and Associates, Minneapolis, MN
A large, complex and expensive software controlled system was developed and deployed. The system consisted of three subsystems; an "AT" type single card computer with associated control electronics, precision three-dimensional movements, and fluidics components with associated control. During the first year of operation in the field, reliability was carefully monitored. Field performance, reliability growth as well as improvement efforts were all monitored for effects on performance. Installation, maintenance and upgrade data were all available.
This system with its complex nature and high degree of documentation could answer the following questions:
Weibull graphical analysis techniques were used to analyze the data from the field and this was compared to a small in house population of systems. Approximately 50 field systems scattered around the U.S. and Canada serve as a stable population for estimating failure rates. Raw data from the field and in house would support a Weibull slope of 0.8 and 1.0 would be a constant failure rate.