Review week 46: robustness

This week was about chips that survive bad days. For review:

• Robust design: check assumptions, first remove NaN from inputs, then limit them with clamp, write every output in every pass, define a safe state.
• Redundancy: two sensors show that something is wrong, three decide by majority. A failed sensor casts no vote, but it has to be reported.
• Failing gracefully: emergency mode instead of standstill, switch off the unimportant first, return only after stable values.
• Start-up: line 0, registers 0, devices keep their state. Before the loop: defined beginning, check memory, switch on staggered.
• Maintainability: settings at the top, clear names, version on the housing.

You pass from 60 %.