Northern Illinois University

Baxter Reliability Laboratory

Reliability Analysis

Our experts can evaluate reliability of repairable items, i.e., Mean Time Between Failures (MTBF), reliability, failure rate, availability, and downtime analysis.  Definitions of these tasks are described below:

Redundancy: The existence of more than one means to accomplish a given function.  Levels of redundancy are: System level (two systems in parallel), sub-system (boards), and components.  Redundancy reduces mission failures but increases logistics failures.  Redundancy means complexity, thus results in increased unscheduled maintenance. 

MTBF: Mean Time Between Failures is a basic measure of reliability for repairable items. 

Reliability:  The duration or probability of failure-free performance under stated conditions.

Availability:  A measure of the degree to which an item is in the operable state at the start of the mission, when the mission is called for at a random time, i.e., the probability that the equipment is down due to required maintenance action.

Downtime:  Amount of time, usually in minutes, that the item is not available to perform its mission. 

When preventative mainenance is planned, the use of redundant equipment can allow for repair with no system downtime.

Preventative maintenance actions provide systematic inspection, detection, and prevention of incipient failures.  This includes the scheduled replacement of items with predictable failure modes.  Scheduled maintenance is preventative maintenance at prescribed points in an items life.