It's unlikely that you could find or rely on software to run on the SME that would successfully detect that hardware problems had caused a system freeze-up, then generate a reboot...
I had an external power module for a Mac years ago that did this - it sat between the power cord and the computer, then had another cord that plugged in to a USB port (I think) - this external device would then physically disconnect and reconnect the power if any of several configurable tests failed (is program xx responding? is the computer responding?, etc)