Monitor Actuator Pair Design Pattern

A previous post discussed patterns for safe systems, including using redundant processors that cross-check. Another accepted pattern for ensuring that there is no single point failure is a Monitor-Actuator Pair. In this...

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Layered Defenses for Safety Critical Systems

Even if designers mitigate all single point faults in a design, there is always the possibility of some unexpected fault or combination of correlated faults that causes a system to fail in an unexpected way. Such failures...

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Redundant Input Processing for Safety

Redundant analog and digital inputs to a safety critical system must be fed to independent chips to ensure no single point failure exists.  (This posting is a follow-on to a previous post about single points of failure.)Consequences: If...

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Self-Monitoring and Single Points of Failure

A previous post discussed single points of failure in general. Creating a safety-critical embedded system requires avoiding single points of failure in both hardware in software. This post is the first part of a discussion...

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