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Archive for the ‘home hacks’ Category

We’ve been told that standing at a desk is good for you, but unless you’re some kind of highly advanced automaton you’re going to have to sit down eventually no matter what all those lifestyle magazines say. That’s where desks like the IKEA SKARSTA come in; they use a crank on the front to raise and lower the desk to whatever height your rapidly aging corporeal form is still capable of maintaining. All the health benefits of a standing desk, without that stinging sense of defeat when you later discover you hate it.

But who wants to turn a crank with their hand in 2019? Certainly not [iLLiac4], who’s spent the last few months working in conjunction with [Martin Mihálek] to add some very impressive features to IKEA’s adjustable table. Replacing the hand crank with a motorized system which can do the raising and lifting was only part of it, the project also includes a slick control panel with a digital display that shows the current table height and even allows the user to set and recall specific positions. The project is still in active development and has a few kinks to work out, but it looks exceptionally promising if you’re looking to get a very capable adjustable desk without breaking the bank.

The heart of the project is a 3D printable device which uses a low-RPM DC gear motor to turn the hex shaft where the crank would normally go. A rotary encoder is linked to the shaft of the motor by way of printed GT2 pulleys and a short length of belt, which gives the system positional information and avoids the complexity of adding limit switches to the table itself.

For controlling the motor the user is given the option between using relays or an H-Bridge PWM driver board, but in either event an Arduino Nano will be running the show. In addition to controlling the motor and reading the output of the rotary encoder, the Arduino also handles the front panel controls. This consists of a TM1637 four digit LED display originally intended for clocks, as well as six momentary contact tactile switches complete with 3D printed caps. The front panel’s simple user interface not only allows for setting and recalling three preset desk heights, but can even be used to perform the calibration routine without having to go in and hack the source code to change minimum and maximum positions.

We’ve seen all manner of hacks and modifications dealing with IKEA products, from a shelving unit converted into a vivarium to a table doing double duty as a cheap plate reverb. Whether you’re looking for meatballs or some hacking inspiration, IKEA seems to be the place to go.

Hackaday.io user [peterquinn] has encountered a problem with his recently unruly cat peeing under the dining table. Recognizing that the household cat’s natural enemy is the spray bottle, he built an automatic cat sprayer to deter her antics.

The build is clear-cut: an Arduino Uno clone for a brain, an MG995 servo, PIR sensor, spray bottle, and assorted electronics components. [peterquinn] attached the servo to the spray bottle with a hose clamp — ensuring that the zero position is pointing at the trigger — and running a piece of cabling around the trigger that the servo will tug on. Adding a capacitor proved necessary after frying the first Uno clone, as the servo powering up would cause the Uno to reset.

The code is set up to trigger the servo — spraying the cat twice — once the PIR detects the cat for more than ten seconds. After toying with a few options, [peterquinn] is using a 9V, 2A power supply that works just fine. For now, he hopes the auto-sprayer should do the trick. If it somehow doesn’t work, [peterquinn] has mused that a drastic upgrade to the vacuum may be necessary.

Gardening is a rewarding endeavour, and easily automated for the maker with a green thumb. With simplicity at its focus,  Hackaday.io user [MEGA DAS] has whipped up a automated planter to provide the things plants crave: water, air, and light.

[MEGA DAS] is using a TE215 moisture sensor to keep an eye on how thirsty the plant may be, a DHT11 temperature and humidity sensor to check the airflow around the plant, and a BH1750FVI light sensor for its obvious purpose. To deliver on these needs, a 12V DC water pump and a small reservoir will keep things right as rain, a pair of 12V DC fans mimic a gentle breeze, and a row of white LEDs supplement natural light when required.

The custom board is an Arduino Nano platform, with an ESP01 to enable WiFi capacity and a Bluetooth module to monitor the plant’s status while at home or away. Voltage regulators, MOSFETs, resistors, capacitors, fuses — can’t be too careful — screw header connectors, and a few other assorted parts round out the circuit. The planter is made of laser cut pieces with plenty of space to mount the various components and hide away the rest. You can check out [MEGA DAS]’ tutorial video after the break!

[MEGA DAS] has made his Arduino code and phone app available to download for anyone else wanting to build their own. Once assembled, he can ensure his plant is well taken care of wherever he is with a few taps on his phone. Not too shabby for a seven day build.

For those preferring gardening outdoors, here’s a hack to jump-start the germinating process of your seeds. Even if you call the concrete jungle your home, that doesn’t mean you can’t have your own robot farm and automated compost bin on hand too!

Is it too much to ask for a home to have a little ‘smart’ built-in? If you’ve ever woken up (or come home) to your dwelling being flooded, you’ll know how terrible it feels, how long it can take to recover from, and how stressful it can be. Yeah, it’s happened to us before, so we really feel for [David Schneider]. He woke up one Sunday morning to a whole lot of water in his house. The inlet valve for his washing machine somehow got stuck in the open position after putting a load of laundry in the previous night.

[David] took progressively complex measures to prevent a broken water feed flood from happening in the future. First, he lined the entire floor of his laundry closet with a steel tray. OK, that’s a good start but won’t prevent another disaster unless it is caught very quickly. How about a simple audible water alarm? That’s good and all if you’re home, but what if you’re not?

Next, he installed a valve with a mechanical timer on the water line for the washing machine which closes automatically after 2 hours of being opened. Much better, but what about all the other thirsty appliances around the house? After searching online a little, he found plenty of whole house systems that would work for him, but there were 2 problems with these. First, most were network-based and he didn’t want to IoT-ify his house’s water system. Second, they were overpriced.

Of course the solution was to put together his own system! First, he purchased a few mostly inexpensive things — a wireless alarm, some water sensors, and a motorized ball valve. Then he collected the last few things he needed from what he had on hand around the house, and got to work connecting the 4 LEDs on the alarm to 4 analog input pins on his Arduino. Next, he added a relay between the Arduino and the motorized ball valve.

If a sensor detects water, it tells the alarm about it (wirelessly), which triggers the Arduino to energize a relay that is connected to the motorized ball valve, causing it to shut off the main water line for the entire house. Disaster averted! Sure, it’s a fairly simple hack, but it works, meets his requirements, and now he sleeps better at night knowing he won’t wake up (or come home) to an indoor swimming pool.

It’s surprising that we haven’t seen more hacks like this given it’s such a common problem. The closest thing we can remember is an overflow sensor for an aquarium. If homes came standard with a water main shutoff system, it would remove a stressful event from our lives and maybe even lower our insurance premium.


Filed under: Arduino Hacks, home hacks

The project itself is very simple: getting push notifications via MQTT when a wireless doorbell sounds. But as [Robin Reiter] points out, as the “Hello, world!” program is a time-honored tradition for coders new to a language, so too is his project very much the hardware embodiment of the same tradition. And the accompanying video build log below is a whirlwind tour that will get the first-timer off the ground and on the way to MQTT glory.

The hardware [Robin] chose for this primer is pretty basic – a wireless doorbell consisting of a battery-powered button and a plug-in receiver that tootles melodiously when you’ve got a visitor. [Robin] engages in a teardown of the receiver with attempted reverse engineering, but he wisely chose the path of least resistance and settled on monitoring the LEDs that flash when the button is pushed. An RFduino was selected from [Robin]’s ridiculously well-organized parts bin and wired up for the job. The ‘duino-fied doorbell talks Bluetooth to an MQTT broker on a Raspberry Pi, which also handles push notifications to his phone.

The meat of the build log, though, is the details of setting up MQTT. We’ve posted a lot about MQTT, including [Elliot Williams]’ great series on the subject. But this tutorial is very nuts and bolts, the kind of thing you can just follow along with, pause the video once in a while, and have a working system up and running quickly. There’s a lot here for the beginner, and even the old hands will pick up a tip or two.


Filed under: Arduino Hacks, home hacks

We’ll admit it: we sometimes overcomplicate things. Look at [Peter Weissbrod’s] automated cat feeder, for example. It isn’t anything more than a bottle, a servo, some odds and ends, and an Arduino. However, it lets him sleep in without his cat waking him for service.

We looked at the code and thought, “This thing will just dispense food all the time! That’s not what you want!” Then we looked closer. [Peter] uses a common household timer to just turn the device on in the morning, let it run for a bit, and then turns it off. You can see a video of the mechanism, below.

Honestly, we have mixed feelings. As we are sure someone’s already quit reading to comment: you don’t really need an Arduino for this. If it were doing the timing, that might make it more justifiable. Or perhaps have it sense daylight to feed in the morning. Still, Arduinos are cheap (we just picked up some tiny Pro’s for about $3) and it is a more flexible arrangement than, say, a 555 driving the servo.

We have seen many cat feeders over the years. Some of them use custom components. Others use whatever you have on hand (including another kitchen timer). However you do it, one thing is clear: When the aliens come and observe life on Earth, they will doubtless conclude that the cats are in charge.


Filed under: Arduino Hacks, home hacks

If you’re waiting for a much sought-after letter, checking your mailbox every five minutes can be a roller-coaster of emotion — not to mention time-consuming. If you fall into this trap, Hackaday.io user [CuriosityGym] as whipped up a mailbox that will send off an email once the snail-mail arrives.

The project uses an Arduino Uno, an ESP 8266 wifi module, and an idIoTware shield board — making specific use of its RGB LED and light dependent resistor(LDR). Configuring the RGB LED on the idIoTware board to a steady white light sets the baseline for the LDR, and when a letter is dropped in the box, the change in brightness is registered by the LDR, triggering the Arduino to send off the email.

idIoTware Mailbox DemoThey used a service called IFTTT — If This Then That — to set up the email process, but feel free to use whatever is most comfortable for you. Be sure to insulate your board properly if you have a metal mailbox! Or, forego the standard letter receptacle and build the smartest mailbox you may ever see.


Filed under: Arduino Hacks, home hacks

[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.

img_2437cropped-resized_thumbnailHe 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.


Filed under: Arduino Hacks, home hacks

Most chickens are pretty good at putting themselves to bed when the sun sets, and [Eddy]’s chickens are no exception. But they’re not terribly thoughtful about closing up after themselves, so he set about on a long-term project to automate the door of their coop.

An open door overnight leaves chickens and their food vulnerable to predation. Rather than handle the chore manually and risk one forgetful moment that could wipe out his flock, [Eddy] used a servo to power the door and an Arduino to control it. To keep track of bedtime and wakeup, a Raspberry Pi looks up the local civil dawn and twilight times online and tells the Arduino when the moment is at hand. The Pi cleverly caches the times for use the next day in case the WiFi connection is down, and also provides a web interface to check on the door’s status and manually override the cycle. Result: safe, happy chickens.

If all this seems a bit much for a simple job, [Eddy] agrees. But he’s using this as a testbed to develop a home automation framework that can be retasked at will. Sounds like he’s on the right track to us, but for more IoT animal husbandry tips, he’ll want to check out this small farm automation effort.


Filed under: Arduino Hacks, home hacks

Tired of being harassed by your cat? [MomWillBeProud] made a cheap, effective — and more importantly cat-operated — cat food dispenser.

The feeder is of an efficient construction — a double cat food dish, one container to store the electronics, and a Pringles can to act as the hopper. A simple servo rotates the hopper thirty degrees and back on each button press; using gravity to drop food through an opening that appears due to this motion. The button itself is an old IKEA timer and a piece of plastic large enough for a hungry cat to swat.

An Arduino controls the servo, and while [MomWillBeProud] skips over going into detail on his code, you can check it out here.

[MomWillBeProud] toyed with the idea of scheduled feeding, but believes his cat is smart enough to feed itself; indeed — training cats is hard work, and it took a couple of weeks for the lessons to sink in. He also recommends using an Arduino Pro Mini, since it consumes so little power that it can operate for months on one set of batteries. Since [MomWillBeProud]’s cat needs a refill only once a week, that’s a lot less time fussing with one’s feline companions.

If you want a similarly hands-off method to ensure your pets have water, we previously featured a project that keeps your pet’s water bowl topped off.

[via /r/DIY]


Filed under: Arduino Hacks, home hacks


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