For whatever reason, [Jeremy] wants to photograph bees in flight. This is one of those things that doesn’t seem that hard until you try to do it. He’s got the mechanical part that can move the camera as fast as the bee flies. But you still have to point the camera correctly. He considered quite a few methods of acquiring and tracking the bee, but he finally settled on a stereo camera. His requirements also made the camera design challenging. In particular, the bees move fast enough that things like USB transmission times become significant. You can see his solution in the video below.
[Jeremy] does a great job explaining all the tradeoffs between frame rate, resolution, focal length, and other optical issues. Of course, he also wanted a global shutter sensor. Rolling shutter cameras scan row-by-row, creating the well-known “jello effect”. Global shutters capture all pixels at once. That also removes any uncertainty as to “when” the shutter fired.
As someone who disassembles and repairs hardware, [Aad] eventually ended up with a huge collection of mixed bolts and screws. This led to creating the automatic bolt and screw sorting system you see here, although in a way it is just a proof of concept. Bolts and screws happen to be a useful application for now, but the system is capable of sorting just about any small objects.
A bit of machine vision detects the size and shape of each object. Weight can also be measured.
Mixed pieces go onto a large conveyor belt, shown on the right. This feeds a few screws at a time down a chute, where they roll onto an illuminated platform.
Above the lit platform is a camera, and machine vision is used to detect the size and shape and orientation of each screw. A robotic gripper on a gantry picks the screws up one by one — separating them first if they happened to clump together — and places each in a drop-off cart. The cart drops the object into a receptacle with its brethren, making sure similar ones are grouped together. Watch it in action in the video, embedded below the page break.
It’s a great build that shows fancy components aren’t necessary for good results. Servos and steppers are controlled with an ESP32-WROOM board, and a piezo sensor detects screws falling off the conveyor. Some of you may have noticed a repurposed Ultimaker 3D printer serving as the bulk of the system, its hot end having been replaced with a gripper that can raise and lower. The overhead camera is an ESP32-CAM adapted to accept M12 lenses so it can focus on the platform.
There’s one more feature worth mentioning — the system also has the ability to measure the weight of a picked object by placing it onto a moveable inspection platform, which can optionally put it under a USB microscope for a closer look. Everything is controlled by a nearby PC, so there’s a lot of flexibility built into the system.
We suppose that once all the screws and bolts in a shop are sorted, it only makes sense to sort all the nuts. Are there other objects besides screws and bolts that would be useful to sort with a system like this? If you have any ideas, don’t keep them to yourself! [Aad] would love to hear your comments and ideas, so share them below.
Hacks don’t have to be practical but it helps if they are educational or clever or amusing, as [Ray Foss] demonstrates with his auto-docking Steam Controller.
It’s an open-source web application that combines a camera, a Steam Controller, and some clever software for the sole purpose of saving the user from the tyranny of having to manually set the controller onto its magnetic charging puck. Instead, one can simply lay the controller down nearby and let the computer do the rest of the work.
First one fires up the web interface, ensures a webcam has a good top-down view of both the charging puck and the controller, connects wirelessly to the controller, then clicks a few points on the camera view to tell the system where things are.
After that, the system buzzes the controller’s haptic feedback motors to make it skitter across the desktop until — guided by the camera and implementing obstacle avoidance — it docks successfully with its magnetic charging puck.
It may not be super practical and may even seem a bit Rube Goldberg-esque, but it’s fun and demonstrates a few interesting things. One is moving a controller via slip-stick friction by asymmetrically pulsing the feedback motors. Another is automatically reducing the pulse frequency to make smaller movements when it gets close to the charging puck, for finer control.
The computer vision part also ignores anything in expected cable locations, removing the need to deal with them algorithmically. WebHID via the browser takes care of talking to the controller, and confirming a successful docking by watching messages to detect when charging has begun.
Ever since the early web, people have been streaming video with inexpensive webcams, and since the advent of the Raspberry Pi and its dedicated camera slot we’ve really seen how easy it can be to build security cameras or any other webcam and get it online quickly. But these cameras notably lack defensive capabilities if anyone tries to break into an area they shouldn’t be, and [John] added some features to this webcam to help defend his garage.
The webcam itself is a custom build, mounted on a custom-built tilt-and-pan mount that lets it freely rotate to view any location in the garage. Some custom software running on a Raspberry Pi lets it operate in autonomous mode or be controlled manually from an Android tablet. But for the defensive capabilities, it also carries a Nerf machine gun with a laser sight and spotlights which can all be controlled autonomously by the Raspberry Pi, including a computer vision system that lets it track various objects. While this is mostly a fun novelty for his security camera, the noise it makes might be enough to startle any would-be burglar.
[John] added a few other features to this build as well, including a speaker, which allows the system to be voice-controlled and to communicate back to the user. This lets him activate and deactivate the system using a verbal password. These types of Nerf guns are fairly popular for turrets as well, and some have practical uses as well like keeping cats from walking on the kitchen counters.
In the world of buzzwords, the acronym ‘AI’ has absolutely been the buzziest of buzzing buzzwords for at least a few years now. Where previously terms like ‘smart’ and ‘intelligent’ sufficed to promote a product, we are now being told that we are living in an age where this supposedly newfangled ‘artificial intelligence’ is doing literally everything faster and better while also curing cancer on the side. Yet, as a wise man once said: “You keep using that word. I do not think it means what you think it means.”
The obvious implication of using a term like ‘artificial intelligence’ in this manner is that it brings to mind a modern version of early last century’s ‘electronic brain’ vernacular alongside the rise of digital computers. Yet rather than electrons in vacuum tubes and semiconductors propelling us into a brave new world of super-intelligence, we now just use said devices to doom scroll and to engage in passive-aggressive online communications like the typical primate groups in a virtual jungle defending their turf.
Similarly, the term AI is massively oversold today, least of all in the inherent presupposition that we somehow have finally cracked the mystery of the brain and have created an intelligence that can go toe-to-toe with humans and even our corvid dinosaur friends. Perhaps the worst part is that there is a veritable mountain of fascinating algorithms and other constructs that help us automate many tasks today, making it somewhat rude to just give up and call everything ‘AI’ like we learned nothing from the 1980s AI craze.
So what is exactly being smoothed over by the glossy marketing of ‘everything is AI’?
While a punch card is perhaps the lowest-density storage medium available, it has some distinct advantages. As [Bitroller] points out in the write-up of his punch card project, if he was using stainless steel instead of PLA his 3D printed punch cards would likely outlast everything he owns, and survive a five-alarm fire to boot. If you have 16 bytes you really, really don’t want to forget — or are willing to store your private key in a shoe box — this project might be of interest.
The nice part is that he’s built a handy Python script to generate printable files for the punch cards, which encode 16 bytes of information and 4 bytes of error correction using the Reed-Solomon algorithm. That’s just enough for a password and the error correction means up to two bytes can be recovered in the case of read failure.
The reading is where this gets interesting — again, [Bitroller] provides a handy script, but this one uses OpenCV to read the entire punch card at once from a webcam image, using the contrast between a black table and the light-colored PLA cards. It’s massively overkill and would have needed a supercomputer in the days when punch cards were common I/O, but that’s what makes this a great hack.
We only have one quibble: if you use additive manufacturing, can you still call it a punch card? Nothing was punched out, after all.
If you think punch cards are totally irrelevant in the modern day, well, you might be right– but that doesn’t stop us from playing with them. If punch cards make you think of Big Iron in the early days of computing, maybe think further back– they were used for everything from Jacquard looms to the original MIDI.
Fish are popular animals to keep as pets, and for good reason. They’re relatively low maintenance, relaxing to watch, and have a high aesthetic appeal. But for all their upsides, they aren’t quite as companionable as a dog or a cat. Although some fish can do limited walking or flying, these aren’t generally kept as pets and would still need considerable help navigating the terrestrial world. To that end, [Everything is Hacked] built a fish tank that allows his fish to move around on their own. We presume he’s heard the old joke about two fish in a tank. One says, “Do you know how to drive this thing?”
The first prototype of this “fish tank” is actually built on a tracked vehicle with differential steering, on which the fish tank would sit. But after building a basic, driveable machine, the realities of fish ownership set in. The fish with the smallest tank needs is a betta fish, but even that sort of fish needs much more space than would easily fit on a robotics platform. So [Everything is Hacked] set up a complete ecosystem for his new pet, making the passenger vehicle a secondary tank.
The new fish’s name is [Carrot], named after the carrots that [Everything is Hacked] used to test the computer vision system that would track the fish’s movements and use them to control the mobile fish tank. There was some configuration needed to ensure that when this feisty fish swam in circles, the tank didn’t spin around uncontrollably, but eventually he was able to get it working in an “arena” where [Carrot] could drive towards some favorite items he might like to interact with. Mostly, though, he drove his tank to investigate the other fish in the area.
The ultimate goal was for [Everything is Hacked] to take his fish on a walk, though, so he set about training [Carrot] to respond to visual cues and swim towards them. In theory, this would have allowed him to be followed by his fish tank, but a test at a local grocery did not go as smoothly as hoped. Still, it’s an interesting project that pushes the boundaries of pet ownership much like other fish-driving projects we’ve seen.
