Creating a Shadow Model to Control Hardware That Cannot Respond back to the Software

[mklotz]

Unless the shadow model can COMPLETELY model all failure mechanisms in the hardware, which is probably impossible, your time is probably better spent instrumenting the hardware to return a state response.

It all depends on the danger level of a hardware failure. If a failure is simply annoying the shadow approach is fine; if it's life-threatening then instrumenting the hardware is in order.