Several years ago I was in a situation in which I desperately needed to get even with someone who had pulled a prank on me just before Christmas. I got one of those 4" clear plastic "photo cubes" and installed a little circuit board containg a phototransistor, a PIC12F675 microcontroller, a battery, and the piezo sounder from a smoke detector. I wrapped the thing in some tissue paper and put a label stating "Do not open until Christmas" on it.
The idea here is that the unsuspecting recipient of the gift will place it under their Christmas tree. After the photoransistor sees light for the first time it "arms" the microcontroller. Once the room lights are all off and sufficient time has elapsed so that the recipient is asleep, the microntroller sounds the smoke detector horn until it detects that the room lights have come back on. Then it goes back to sleep until the lights have been off for an hour.....and the process repeats until the battery is depleted or the device gets smashed to bits...whichever comes first.
Earlier this year, we moved into a new condo, where I discroved a number of equipment that meeps, beeps and talks.
Aside from our talking elevator (which I hate because it has this phony non-American accents), it was (and still is) a mystery to me for several months what the meep sound was all about in our kitchen.
I know our fridge speaks (don't ask me why), when the door is kept open for too long.
But there is this meep sound that occasionally comes up.
I first suspected that it was our fridge, but it is not consistent. It meeps once in a while but never at a constant interval.
Because it doesn't happen often enough, nor it lasts long enough, I could forget about it after five minutes... But i would sure like to know where that meep sound is coming from!
While not a "meep" case, I heard a classic story about presents.
A couple of brothers had a friendly birthday present competition. The present was always the same - a pair of jeans they passed back and forth. The challenge was unwrapping it to pass it back the next time the other brother's birthday rolled around.
At the point I heard the tale, brother one had the jeans to give to brother two. He went to a junk yard and bought a junked car. He put the jeans on the back seat, then had the junkyard run the junker through the machine that converted the junked car to a crushed rectangular block suitable for resale to a scrap metal dealer to be melted down and recast.
He then had a truck deposit the block on his brother's lawn, with a Happy Birthday card attached.
Go ahead. Unwrap it. Pass the jeans back to me on my birthday. Bet you can't...
@Max: "Dare we ask what the prank was that your (ex) friend pulled on you?"
@DMcCunney: "He then had a truck deposit the block on his brother's lawn, with a Happy Birthday card attached."
That story is hauntingly familiar. Here's what happened to me to trigger my revenge.
A couple of weeks before Christmas that year a UPS freight truck with a liftgate pulled up at my house. They had a crate that "appeared" to be from Hewlett Packard. It had been sent priority overnight, freight collect. I was expecting a repaired laser printer ot be returned to me, but I wasn't expecting priority overnight shipping, and the crate was WAAY to big and heavy. Curiosity got the best of me, so I agreed to pay the shipping charges. I eagerly opened it after it was deposited in the carport, only to find a rusty V8 engine block in the crate.
Of course, this meant war. The perpitrator of this prank was unfortunate enough to receive "gifts" from me at Christmas over the next several years.
@RCurl: Of course, this meant war. The perpitrator of this prank was unfortunate enough to receive "gifts" from me at Christmas over the next several years.
Did you ever find out why the perpetrator pulled his prank?
Another classic car related prank was the story I heard about a chap who got a foreign import with high gas milage, and promptly proceeded to annoy everyone with his raving about his milage. So his co-workers decided to play with his head.
Each day, one of them would go out to the company lot and siphon gas into his tank. He went weeks without having to get a refill. He raved to the dealer he'd bought the car from about his wonderful milage. The dealer knew what he reported wasn't possible, but they weren't about to try to bust a very satisfied customer's balloon.
Then the co-workers reversed their strategy and starting siphoning gas out of his tank. His gas milage plummeted. He went to the dealer screaming that they had to fix the problem. Of course, there was nothing they could fix.
His co-workers finally took pity on him, stopped the rank, and told him what had been going on and why. Whether he learned from the experience was not reported,
"It makes you wonder if there's a market for a 'meep detector' that could work out where the sound is coming from and guide you to it..."
I strongly suspect there is. Nearly everyone who has smoke detectors at home has experienced the late night meeping of those things, and now we have so many other devices that want to complain about something in the same annoying manner -- refrigerator door open, microwave oven done cooking, etc.
You should draw up a business plan, Max, and Kickstarter this thing!
Musical greeting cards are a cheap way to get into the game, especially the cards that play annoying tunes like "Happy Birthday". If you choose the location carefully, room reflections make them difficult to find. The trick is to avoid direct sound so that the sound seems louder as you move away from it. The top of a bookcase, near the ceiling is good. Point the "speaker" at another wall. The direct sound goes over the head and seems to be coming from the wall.
What are the engineering and design challenges in creating successful IoT devices? These devices are usually small, resource-constrained electronics designed to sense, collect, send, and/or interpret data. Some of the devices need to be smart enough to act upon data in real time, 24/7. Are the design challenges the same as with embedded systems, but with a little developer- and IT-skills added in? What do engineers need to know? Rick Merritt talks with two experts about the tools and best options for designing IoT devices in 2016. Specifically the guests will discuss sensors, security, and lessons from IoT deployments.