Vibrosight Hears When You Are Sleeping. It Knows When You’re Awake.

October 22, 2018 by Tom Nardi 16 Comments

No matter how excited you are to dive headfirst into the “Internet of Things”, you’ve got to admit that the effort and expense of going full-on Jetsons is a bit off-putting. To smarten up your home you’ve generally got to buy all new products (and hope they’re all compatible) or stick janky after-market sensors on the gear you’ve already got (and still hope they’re all compatible). But what if there was a cheap and easy way to keep tabs on all your existing stuff? The answer may lie in Cold War era surveillance technology.

As if the IoT wasn’t already Orwellian enough, Vibrosight is a project that leverages a classic KGB spy trick to keep tabs on what’s going on inside your home. Developed by [Yang Zhang], [Gierad Laput] and [Chris Harrison], the project uses retro-reflective stickers and a scanning laser to detect vibrations over a wide area. With this optical “stethoscope”, the system can glean all kinds of information; from how long you’ve been cooking something in the microwave to whether or not you washed your hands.

The project takes its inspiration from the optical eavesdropping system developed by Léon Theremin in the late 1940’s. By bouncing a beam of light off of a window, Theremin’s gadget was able to detect what people inside the room were saying from a distance. The same idea is applied here, except now it uses an automated laser scanner and machine learning to turn detected vibrations into useful information that can be plugged into a home automation system.

For Vibrosight to “listen” to objects, the user needs to place retro-reflective tags on whatever they want to include in the system. The laser will periodically scan around the room looking for these tags. Once the laser finds a new tag, will add it to a running list of targets to keeps an eye on. From there Vibrosight is able to take careful vibration measurements which can provide all sorts of information. In the video after the break, Vibrosight is shown differentiating between walking, jogging, and running on a treadmill and determining what kind of hand tools are being used on a workbench. The team even envisions a future where Vibrosight-ready devices would “hum” their IP address or other identifying information to make device setup easier.

If all this talk of remote espionage at a distance has caught your interest, we’ve covered Theremin’s unique surveillance creations in the past, and even a way to jam them if you’re trying to stay under the radar.

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Fighting Machine Tool Chatter With A 555 Timer

October 6, 2017 by Dan Maloney 32 Comments

Vibration is a fact of life in almost every machining operation. Whether you’re milling, drilling, turning, or grinding, vibration can result in chatter that can ruin a part. Fighting chatter has generally been a matter of adding more mass to the machine, but if you’re clever about things, chatter reduction can be accomplished electronically, too. (YouTube, embedded below.)

When you know a little something about resonance, machine vibration and chatter start to make sense. [AvE] spends quite a bit of time explaining and demonstrating resonance in the video — fair warning about his usual salty shop language. His goal with the demo is to show that chatter comes from continued excitation of a flexible beam, which in this case is a piece of stock in the lathe chuck with no tailstock support. The idea is that by rapidly varying the speed of the lathe slightly, the system never spends very long at the resonant frequency. His method relies on a variable-frequency drive (VFD) with programmable IO pins. A simple 555 timer board drives a relay to toggle the IO pins on and off, cycling the VFD up and down by a couple of hertz. The resulting 100 RPM change in spindle speed as the timer cycles reduces the amount of time spent at the resonant frequency. The results don’t look too bad — not perfect, but a definite improvement.

It’s an interesting technique to keep in mind, and a big step up from the usual technique of more mass.

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A Fix For The Lightweight Machine Tool Shakes

September 16, 2017 by Dan Maloney 12 Comments

No matter what material you work with, the general rule is that with machine tools, the heavier, the better. Some people can’t afford or don’t want big tools, though, even with their natural tendency to reduce vibrations. That doesn’t mean something can’t be done to help the little tools, like reducing vibration in a contractor-grade table saw.

This one might seem a little outside the usual confines of the hackosphere, but nobody can doubt [Matthias Wandel]’s hacker chops and he really shows off his problem-solving skills with this one. His well-worn contractor-style table saw has had more than a few special modifications over the years, some of which left it with a shimmy sufficient to vibrate workpieces right off the table. He fashioned a friction damper for the saw’s motor from wood, complete with ball and socket joints to allow full movement of the blade height and angle. That didn’t quite do the trick, but his incremental approach finally found the right combination of factors, and the video below shows a saw now stable enough to balance a nickel.

If the name seems familiar but you just can’t place the hacks, check out [Matthias]’s recent wooden domino extruder, his shortcuts to tapping wood, or of course his classic wood gears layout software.

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Bulking Up A Lightweight Lathe With A Concrete Cart

March 5, 2017 by Dan Maloney 21 Comments

When it comes to machine tools, a good rule of thumb is that heavier is better. A big South Bend lathe or Bridgeport mill might tip the scales at ludicrous weight, but all that mass goes to damping vibration and improving performance. So you’d figure a lathe made of soda cans could use all the help it could get; this cast concrete machine cart ought to fit the bill nicely

Perhaps you’ve caught our recent coverage of [Makercise]’s long and detailed vlog of his Gingery lathe build. If not, you might want to watch the 5-minute condensed video of the build, which shows the entire process from melting down scrap aluminum for castings to first chips. We love the build and the videos, but the lightweight lathe on that wooden bench never really worked for us, or for [Makercise], who notes that he was never able to crank the lathe up to full speed because of the vibrations. The cart attempts to fix that problem the old fashioned way – more mass.

There are a few “measure twice, cut once” moments in the video below, as well as a high pucker-factor slab lift that could have turned into a real disaster. We might have opted for a countertop-grade concrete mix that could be dyed and polished, but that would be just for looks. When all is said and done, the cart does exactly what it was built to do, and there’s even room on it for the shaper that’s next on the build list. We’re looking forward to that.

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Keep The Peace In The Bedroom With A Snore Stopping Sleep Mask

February 22, 2017 by Dan Maloney 29 Comments

Despite what my wife says, I have absolutely no evidence that I snore. After all, I’ve never actually heard me snoring. But I’ll take her word for it that I do, and that it bothers her, so perhaps I should be a sport and build this snore-detecting vibrating sleep mask so she can get a few winks more.

Part wearable tech and part life hack, [mopluschen]’s project requires a little of the threadworker’s skill. The textile part of the project is actually pretty simple, and although [mopluschen] went with a custom mask made from fabric and foam shoulder pads, it should be possible to round up a ready-made mask that could be easily modified. The electronics are equally simple – an Arduino with a sound sensor module and a couple of Lilypad Vibe boards. The mic rides just above the snore resonating chamber and the vibrators are right over the eyes. When your snore volume exceeds a preset threshold, the motors wake you up.

Whether this fixes the underlying problem or just evens the score with your sleep partner is debatable, but either way there’s some potential here. And not just for snore-correction – a similar system could detect a smoke alarm and help rouse the hearing impaired. But if the sewing part of this project puts you off, you should probably check out [Jenny List]’s persuasive argument that sewing is not just for cosplayers anymore.

Appliance Monitor Is Kinda Shaky

January 8, 2017 by Lewin Day 24 Comments

Lots of people set out to build appliance monitors, whether it be for the fridge, the garage door, or the washing machine. Often, it’s nicer not to cut into an appliance to make direct electrical connections, especially when mains power or water is involved. But how else can we know what the appliance is doing?

[Drew Dormann] wanted to smarten up his old washing machine, so designed a system that uses a vibration sensor to monitor appliances. It’s a simple build, pairing the 801s vibration sensor with a Raspberry Pi Zero. Naturally, adapter boards are readily available to make hooking things up easy. Then it’s just a matter of tying it all together with a simple Python script which sends notifications using Twitter & PushBullet.

It’s important to note that this approach isn’t just limited to washing machines – there’s a whole laundry list of home appliances that vibrate enough to be monitored in this way! It’s likely you could even spy on a communal microwave in this way, though you might struggle with WiFi dropouts due to interference. Build it and let us know.

[Drew]’s build is a great example of what you can put together in a few hours with parts off the shelf. For those that consider the Pi Zero overkill for this application, consider this vibration-based laundry monitor based on the ESP8266. Think you can do better? Show us what you’ve got on Hackaday.io!

Launitor Saves You From Accidentally Smelly Clothes

November 10, 2016 by Gerrit Coetzee 19 Comments

[domiflichi] is human and fallible. So he can’t be blamed for occasionally forgetting the laundry in one of the machines and coming back to a less than stellar result. However, while fallible, he is not powerless.

What if his washer/dryer could email or text him about his laundry? It seemed simple enough. Add a vibration sensor to the side of the machine along with some brains. When the load is done it will bother him until he comes down to push the button or There Will Come Soft Rains.

He started off with an Arduino-and-ESP8226 combination and piezo sensors. The piezos had lots of shortcomings, so he switched to accelerometers and things worked much better. We really like the way he mounts them to the side of the washer dryer using the PCB’s mounting screws as angle brackets. The case is a standard project box with some snazzy orange acrylic on the front.

It took some fiddling, but these days [domiflichi]’s clothes are fresher, his cats fed, and his appliances more aware. Video of it in operation after the break.

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