Ok… I live in an area that has a lot of gigantic evil centipedes that have a very painful bite and can be fatal to children… When I’m home I can properly defend the family from these evil beasts. When I’m away on business I have to leave my wife and kids vulnerable to the demon spawns. I’m trying to come up with a smart device that will either kill or prevent these pests from entering my home. Any ideas? We have giant roaches also but they don’t bite so I’m not too concerned. I thought of some kind of electric bug fence to go around the exterior base of the home but it would be neat if it could somehow signal when a large pest was present… Seriously… my wife would sleep easier:)
Dog?
For “wet” bugs like snails / slugs & leaches, a low voltage across 2 strips of foil tape works very well. AC is better than DC, as it will reduce electrolytic corrosion.
However, I don’t think the conductivity of centipede / roach legs will be enough to make this work at low (safe) voltages. You could do an experiment with an adjustable power supply I guess. Even if this works, I’m not sure how practical detection will be, as you’ll get false positives from any moisture across the electrodes.
I suspect you may have to stick with old-fashioned methods like making sure there are no holes in the house that insects can fit through, as well as chemical barriers 
I once saw an episode on techTV where a guy built a bunch of dog bowls and what not that had a defense against giant ants. I assume that the resistance couldn’t be too much greater for the roaches or the centipedes. He used a 9V battery as the power sources, but like the poster above said, AC would be better. He used two strands of copper foil tape spaced about 2 mm apart, and when the ants stepped across it, well, you could guess.
Where I lived once ants started invading the kitchen via the front door. I put a dollop of jam in a container by the door, and they stopped coming into the kitchen. I had to renew the jam every every couple of weeks. Perhaps something similar would keep centipedes out. I doubt if they like jam but some scraps of meat might work.
Leon, baby powder works wonders, they take it back to the nest and kill all the others.
Not sure why that would kill ants (it's just talc or cornstarch with fragrance), but pretty much any compound with Boron in it (eg Borax) is deadly to insects when consumed. Mixed with honey it will take out the whole nest...Philipf:
Leon, baby powder works wonders, they take it back to the nest and kill all the others.