By Bill Graham
The recent news about the demise of the Mars Rover Spirit (Mike Deliman blogged about this last week) and comments about how it succeeded its mission many times over, got me thinking about just how long product lifetimes are for embedded products (see "End of Mars mission: Way beyond warranty" by Bob McDonald at the CBC). In many industries using embedded software to control devices, the expected lifespan is decades which contrasts sharply to consumer devices where either software is upgraded constantly or we dispose of the device in a few years. On the other hand, embedded systems often exceed originally planned lifespans many times over. Case in point is the Mars Rover program, where Spirit operated six years beyond its original mission plan and rover Opportunity continues operation, surviving a harrowing journey and landing and a harsh Martian environment for so many years.