The title of this blog post may seem to poke fun at simulations, but it’s based on a story recounted in a blog post entitled Simulation: Fact or Fantasy?. In it, Joel Orr describes a NASA engineer’s outrage at his use of the phrase “trial and error” to characterize the design process. The engineer asserted that error had no part in design.
The point that Joel was trying to make (and did make in that post), was that errors — when things don’t come out the way we expect — are valuable sources of information about designs and assumptions. Historically, obtaining such instructive errors required the development and testing of real-world prototypes. However, simulations of all kinds are enabling engineers to test virtual prototypes faster and at a lower cost than was ever possible in the past.
Think about the cost involved in testing even a prototype sensing and therapy algorithm for an existing ICD and lead. Some simple checks can be done by hooking up a programmed device to a pre-programmed input (this is simulation!). However, to fully test the algorithm, an animal study must be done. This brings in the costs in money and time of acquiring, caring for, and doing test procedures on a large enough number of animals to reach statistical significance. Testing the algorithm in a simulated heart requires only one model, whose shape, electrophysiological characteristics, disease status, and starting state may easily be varied over a wide range of parameters. It can be done in a matter of hours or days instead of weeks or months.
What kinds of errors are you taking too long to make now?