Complete Array of Tools for Related Analyses
Reliability Block Diagrams to Analyze Failure Modes
The Competing Failure Modes option has been a very popular feature among Weibull++ users. The Reliability Block Diagram (RBD) feature that has been added to Version 7 provides a huge leap forward in both flexibility and analytical power. Now there is no limit to the number of failure modes that you can consider and each mode can be analyzed individually with the appropriate lifetime distribution. In addition, you can use the flexible RBD interface (patterned after the intuitive BlockSim diagram utility) to describe the reliability-wise relationships among the modes (i.e. series, parallel, k-out-of-n) and thereby model the failure behavior more accurately and realistically. Using the exact algebraic reliability equation for the configuration that you've defined, Weibull++ provides common reliability results and plots at the click of a button. You can even consider the uncertainty of the fitted parameters of each data set to calculate confidence bounds on the overall reliability metrics!
Recurrent Event Data Analysis
"Life Data Analysis" methods deal with units that experience only one event, end of life. In contrast, other applications involve repeated events data where a sample unit may accumulate any number of events over time. Examples include number of repairs on a product, number and treatment of recurrent disease episodes, etc.
Weibull++ 7 provides both parametric and non-parametric approaches to analyze such recurrent event data. The non-parametric approach is based on the well-known Mean Cumulative Function (MCF). The parametric approach is based on the General Renewal Process (GRP) model, which is particularly useful in understanding the effects of repairs on system age.
