There have been many robots and AIs in science fiction over the years, from Astro Boy to Cortana, or even Virgil for fans of the long-forgotten Crash Zone. However, all these pale into insignificance in front of the cold, uncaring persona of the HAL 9000. Thus, [Jürgen Pabel] thought the imposing AI would make the perfect home assistant.
The build is based on a Raspberry Pi Zero 2, which boasts more grunt than the original Pi Zero while still retaining good battery life and a compact form factor. It’s hooked up with a 1.28″ round TFT display which acts as the creepy glowing eye through which HAL is supposed to perceive the world. There’s naturally a speaker on board to deliver HAL’s haunting monotone, and it’s all wrapped up in an tidy case that really looks the part. It runs on the open-source voice assistant Kalliope to help out with tasks around the home.
When you’re lucky enough to have a dog in your life, you tend to overlook some of the more one-sided aspects of the relationship. While you are severely restrained with regard to where you eliminate your waste, your furry friend is free to roam the yard and dispense his or her nuggets pretty much at will, and fully expect you to follow along on cleanup duty. See what we did there?
And so dog people sometimes rebel at this lopsided power structure, by leaving the cleanup till later — often much, much later, when locating the offending piles can be a bit difficult. So naturally, we now have this poop-shooting laser turret to helpfully guide you through your backyard cleanup sessions. It comes to us from [Caleb Olson], who leveraged his recent poop-posture monitor as the source of data for where exactly in the yard each deposit is located. To point them out, he attached a laser pointer to a cheap robot arm, and used OpenCV to help line up the bright green spot on each poop.
But wait, there’s more. [Caleb]’s code also optimizes his poop patrol route, minimizing the amount of pesky walking he has to do to visit each pile. And, the same pose estimation algorithm that watches the adorable [Twinkie] make her deposits keeps track of which ones [Caleb] stoops by, removing each from the worklist in turn. So now instead of having a dog control his life, he’s got a dog and a computer running the show. Perfect.
We joke, because poop, but really, this is a pretty neat exercise in machine learning. It does seem like the robot arm was bit overkill, though — we’d have thought a simple two-servo turret would have been pretty easy to whip up.
Sending postcards to loved ones used to be standard procedure for travelers back when travel was glamorous and communications were slow. While some travelers still keep this tradition alive, many have replaced stamps and post offices with instant messaging and social media — faster and more convenient, but a lot less special than receiving a postcard with a handwritten message from a faraway land.
[Cameron] designed a postcard picture frame that aims to bring back a bit of that magic. It’s a wooden frame that holds an e-ink display, which shows pictures sent to it by your friends. All they need to do is open the unique link that you sent them beforehand and upload an interesting photo; the picture frame will cycle through the submissions based on an adjustable schedule. A web interface allows you to change settings and delete any inappropriate images.
The wooden frame is beautifully made, but the sleek black PCB inside is an true work of art. It holds a battery and a USB-C charging circuit, as well as an ESP32 that connects to WiFi, stores images and downscales them to the 800×480 monochrome format used by the display. [Cameron] has not accurately measured the current consumption, but estimates that it should work for about one year on a single charge thanks to the extremely low power requirements of e-ink displays.
Having your friends decide on the images shown in your house is an interesting idea, if you can trust them to keep it decent. If you like to have more control over your e-ink display, have a look at this solar-powered model or this wall-mounted newspaper display.
We’ve all been there. Pigeons are generally pretty innocuous, but they do leave a mess. If you have a convertible or a bicycle or even just a clean car, you probably don’t want them hanging around. [Max] was tired of a messy balcony, so like you might approach any engineering problem, he worked his way through several possible solutions. Starting with plastic crows, and naturally ending with an automated water gun.
The resulting robotic water gun that targets pigeons with openCV is a dandy project and while we don’t usually advocate shooting at neighborhood animals, we don’t think a little water will be any worse than the rain for the pigeons. The build started with a cheap electric water pistol. A Wemos D1 Mini ESP8266 development board provides the brainpower. The water pistol wouldn’t easily take rechargeable batteries, plus it is a good idea to separate the logic supply and the pump motors, so the D1 gets power from a USB power bank separate from the gun’s batteries.
That leaves the camera. An old iPhone 6S with a 3D printed bracket feeds video to a Python script that uses openCV. If looks for changes using a very particular algorithm to detect that something is moving and fires the gun. It doesn’t appear that it actually tracks the pigeons, so maybe that’s a thought for version 2.
Was it successful? Maybe, but it does seem like the pigeons learned to avoid it. We still think azimuth and elevation on the gun would help.
Most of the time when we see pigeon hacking it is to use them for nefarious purposes. [Max] should be glad he doesn’t have to deal with lions.
Plenty of potential, but a cozy hacking space it is not
To us hackers and makers, the tools of our trade are often as important and interesting as the details of the hacks themselves, but what about the most important tool of all — the very space you use to make your magic happen? That may be your bedroom, a nearby hackerspace, and if you have the resources, you may even own a place of your own, and get to build your perfect workspace.
The latter situation is what [MichD] and partner [Brittany] found themselves in, having moved into their first place. Many couples focus on getting a hot tub in the garden or sorting the nursery, but these two are proper electronics nerds, so they converted a free-standing double wide garage into the nerdhub, learning as they went along, and documenting it in excruciating detail for your viewing pleasure.
Door fitted, framed up, and insulation in place. All ready for plasterboarding.
The building structurally is a single-skinned brick-built box, with a raw concrete floor. Pretty typical stuff for the UK (we’ve seen much worse), but not ideal for spending an extended amount of time in due to our damp, cold climate, at least in winter.
The first order of business was partitioning the front section for bike storage, and screeding the floor. Once the floor was solid, the walls and ceiling joists could be framed up, ready for fitting insulation material and covering with plasterboard.
Electrics were next in order, with the wires clipped to the brickwork, well away from where the plasterboard would be, therefore making it less likely to accidentally drill into a live cable when adding external fixtures.
Since the front part of the room was to be partitioned off, another access door was needed. This involved cutting out the bricks to fit a concrete lintel. With that installed, and the bricks above supported, the area below was cut out to the required shape. A somewhat nerve-wracking experience, if you ask us!
As any self-respecting hacker will tell you — no room build is complete without a decent amount of RGB bling, so the whole room was decked out with APA102 addressable LED strips. Control of these was courtesy of WLED running on an ESP32 module, with LedFX used on a nearby PC to perform music visualisation, just because.
We’ve all at some point in our lives opened the fridge door and immediately wished we hadn’t. A miasma of stench envelops us as we discover that last Saturday’s leftovers have been forgotten, and have gone off. If only we had some way to keep track of such things, to avoid such a stench-laden moment. Step forward [ThinkLearnDo], with a little timer designed for exactly that purpose.
The operation is simple enough, press the button and place the unit on top of the container with the leftovers in it. If you haven’t eaten the leftovers within a week, the LED will start blinking. The blink is a subtle reminder to deal with the old food before it becomes a problem.
Onboard is a Holtek HT68F001 microcontroller with a coin cell for power, not much else is needed. The Holtek is an unusual choice, one of several brands of super-inexpensive Chinese microcontrollers we see less commonly than ATmegas and STM32s. This is exactly the place where such a minimal computer fits perfectly: a way to add a little bit of smarts to a very cheap item with minimal strain on the BoM.
When it comes to interpreting sensor data automatically, it helps to have a large data set to assist in validating it, as well as training when it concerns machine learning (ML). Creating this data set with carefully tagged and categorized information is a long and tedious process, which is where the idea of cross-domain translations come into play, as in the case of using millimeter wave (mmWave) radar sensors to recognize activity of e.g. building occupants with the IMU2Doppler project at Smash Lab of Carnegie Mellon University.
The most commonly used sensor type when it comes to classifying especially human motion are inertial measurement units (IMU) such as accelerometers and gyroscopes, which are found in everything from smartphones to smart watches and fitness bands. For these devices it’s common to classify measurement patterns as matches a particular activity, such as walking, jogging, or brushing one’s teeth. This makes them both well-defined and very accessible.
As for why a mmWave-based Doppler radar would be preferred for monitoring e.g. building occupants is the privacy aspect compared to using cameras, and the inconvenience of equipping people with a body-worn IMU. Using Doppler radar it would theoretically be possible for people to track activities within their own home, as well as in a medical setting to ensure patients are safe, or at a gym to track one’s performance, or usage of equipment. All without the use of cameras or personal sensors. In the past, we’ve seen a similar approach that used targeted laser beams.
As promising as this sounds, at this point in time the number of activities that are recognized with reasonable accuracy (~70%) is limited to ten types. Depending on the intended application this may already be sufficient, though as the published paper notes, there is still a lot of room for growth.
