I had to swap the release order of my most recent videos, so the PCBWay video got released first otherwise the Xmas competition details would have been out of date before it got seen.
This means my next video is all about dogs. Dogs that bark. In particular, our current dog, Dougle, for whom we are custodians, (yes, it really is spelt like that, courtesy of my daughter).
He’s a great dog in many ways but suffers from small dog syndrome. That is, everything that’s his is his – and everything that he can see is his, which means that he can be very territorial.
When someone, such as the Amazon delivery guy or the postman rings the bell or knocks on the door he goes ballistic with his barking. We’ve tried to be stern and say “STOP!” which he acknowledges for about 1µS before resuming his barking. For a small dog, he can be really loud. 📣
So we’ve resorted to an ultrasonic barking deterrent module. This emits a high-pitched sound (ca. 22KHz) which he is supposed to find an irritant. When he barks, it goes off. When he stops, it stops too. Eventually, he is supposed to associate the two events, but as he’s a sandwich short of a picnic it might take a while. No offence, Dougle. 🐕
So why ultrasonic? Firstly, we have no desire to cause him distress. Discomfort, maybe, but then that is under his control (when he figures out the correlation between his barking and that really annoying sound).
And we don’t want anything around his collar, because firstly, he’s a small dog and anything fitted around his collar looks disproportionately large. If he were a Labrador it might be OK, but not a mini Yorkie. Secondly, it would be too much in his face. This is a good behaviour learning-aid, not a punishment device. No shock collars here, thank you!
So video #129 shows a simple microphone amplifier feeding into an Arduino which provides the intelligence to switch on (and off) the WEMO German-built ultrasonic device. It’s actually designed to prevent pine martens from getting into your car’s engine bay and wreaking havoc with your car’s wiring, which they love to eat. Quite a problem in Germany, apparently.
I finally deployed the prototype (as in breadboard, Arduino and ultrasonic device all stuck onto a piece of board with BluTack) just to see how (and if) it would work. It currently looks ugly but there’s no point in making it pretty if it doesn’t work, which may take weeks. If we notice that Dougle is starting to take note I’ll then tart it up and put it in some sort of project box, add a couple of pretty LEDs and so on.
The intelligence I mentioned comes from the code. It’s designed to be in standby mode by default, moving to DEFCON 1 after one bark and then launch a missile (switch on the ultrasonic device) on the next bark. It switches off after one second if he’s stopped barking. There’s a bit more to it and remains a work in progress, but I have a working prototype.
If it works, that’s a big IF, I might build a second one for the car, as it runs off 12 volts. Or make it portable with 3 Li-Ion batteries. Possibilities abound. I could even design a proper PCB for it and sell it.
This time next year, Dougle, we’ll be millionaires. And silence will abound. 😂
1Apologies to Fools & Horses – an English sitcom starring David Jason and Nicholas Lindhurst. Del Boy (Jason) was a wheeler dealer with always some get-rich-quick scheme on the go. His catchphrase was: This next next year, Rodney, we’ll be millionaires. See this excerpt