Field Reliability Data Analysis

Basic Definitions

• Reliability: Ability to provide continuous and stable system/component function under defined operating conditions without failure(s).
• Mean Time Between Failures (MTBF): Average expected time interval between failures. Often a measure of reliability.
  • Failure Rate is the expected no. of failures over a period of time. MTBF is the inverse of failure rate.
• Availability: Percentage of time a system or component can perform its intended function without failure.   
  • Key aspects involve individual component reliability, system architecture, redundancy, and implementation of control strategies to ensure uninterrupted service. 
  • Availability = Uptime/(Total Operation Time) = MTBF/(MTBF+MTTR), MTTR is a measure of time to repair the system/component
  • For example, 99.999% (5-9’s of availability) -> 5 min downtime in one year
• Reliability Block Diagram: Reliability Block Diagram (RBD) is a graphical representation used to model reliability in complex systems. Illustrates interconnections between various components or subsystems within a system.

A one-sample t-test is a statistical test to determine if the sample mean differs significantly from a known or hypothesized population mean (expected value). It is commonly used when we have a single sample and want to compare its average to an expected value.

In the current century, data is ubiquitous but how to make use of it to drive product decisions can take time and effort. Data visualization is a useful technique to identify patterns in a dataset and derive exploratory statistics to analyze trends.