Stuff that tends to go wrong with fursuit electronics…
Flexing PCB’s – and multi-layer ceramic capacitors specifically
PCB’s placed in paws and other places may flex a little. Sometimes you can get away with it but sometimes things on the PCB can break, possibly catastrophically. Dave Jones found that multi-layer ceramic capacitors can break, fail short, and go boom! (video) Dave’s recommendations to deal with it: (video) I’d guess the best thing is to avoid flexing in the first place. Dave also suggests putting two MLCC’s in series, so if one fails short, the other will still work, but if both break…
Sweat
Sweat will short out circuits and even if it doesn’t go boom, it’s enough to make microcontrollers do weird things. Solution? I tried conformal coating the PCB’s but it wasn’t enough. Wrapping the PCB’s in electrical table worked. Friction tape / self-adhering tape may be another option. Putting the PCB’s in project boxes is the obvious solution if there’s room for it.
Program locks up
I’ve seen this happen to another electronic fursuiter – they had to put a paperclip across the reset pins to fix the problem. A better solution might be to incorporate a reset button into the design, but I never bothered. Instead I used the watchdog timer, and put programming headers on the boards so problems could be more easily fixed.