[Kevin Norman] got himself a smart body scale with the intention of logging data for his own analysis, but discovered that extracting data from the device was anything but easy. It turns out that the only way to access data from his scale is by viewing it in a mobile app. Screen-scraping is a time-honored method of pulling data from uncooperative systems, so [Kevin] committed to regularly taking a full-height screenshot from the app and using optical character recognition (OCR) to get the numbers, but making that work was a surprisingly long process full of dead ends.
First of all, while OCR can be reliable, it needs the right conditions. One thing that ended up being a big problem was the way the app appends units (kg, %) after the numbers. Not only are they tucked in very close, but they’re about half the height of the numbers themselves. It turns out that mixing and matching character height, in addition to snugging them up against one another, is something tailor-made to give OCR reliability problems.
The solution for this particular issue came from an unexpected angle. [Kevin] was using an open-source OCR program called Tesseract, and joined an IRC community
#tesseract to ask for advice after exhausting his own options. The bemused members of the online community informed [Kevin] that they had nothing to do with OCR;
#tesseract was actually a community for an open-source 3D FPS shooter of the same name. But as luck would have it, one of the members actually had OCR experience and suggested the winning approach: pre-process the image with OpenCV, using
cv2.findContours() to detect and create a bounding box around each element. If an element is taller than a decimal point but shorter than everything else, throw it out. With that done, there were still a few more tweaks required, but the finish line was finally in sight.
Now [Kevin] can use the scale in the morning, take a screenshot, and in less than half a minute the results are imported into a database and visualizations generated. The resulting workflow might look like something Rube Goldberg would approve of, but it works!
We all know what it means to procrastinate, but what about actively spending time building a useless machine? You have undoubtedly seen the ornamental boxes with a tempting little toggle switch on the top. When you inevitably flip the switch, an actuator pops out from one half of the enclosure with the sole purpose of undoing its own power switch. [Paz Hameiri] took it a step further by adding some [Rube Goldberg] flavor, and with the help of a microcontroller, his levers take their sweet time powering themselves down. (Video after the break.)
We didn’t find any code or diagrams for the project, but if you know the useless machine’s internals, it shouldn’t be any trouble to recreate one for your desk. The most significant design factor is that the switches. Their contacts must be wired in parallel so that the controller has power as long as one is active. How would you spice up the useless machine?
Even though these are called useless machines, they serve the purpose of decoration, conversation-starting, or a way to show off your woodworking and programming skills.
Continue reading “Complicated And Useless Cancel Each Other Out”
The name Rube Goldberg has long been synonymous with any overly-built contraption played for laughs that solves a simple problem through complicated means. But it might surprise you to learn that the man himself was not an engineer or inventor by trade — at least, not for long. Rube’s father was adamant that he become an engineer and so he got himself an engineering degree and a job with the city. Rube lasted six months engineering San Francisco’s sewer systems before quitting to pursue his true passion: cartooning.
Rube’s most famous cartoons — the contraptions that quickly became his legacy — were a tongue-in-cheek critique meant to satirize the tendency of technology to complicate our lives in its quest to simplify them. Interestingly, a few other countries have their own version of Rube Goldberg. In the UK it’s Heath Robinson, and in Denmark it’s Robert Storm Petersen, aka Storm P.
Rube Goldberg was a living legend who loved to poke fun at everything happening in the world around him. He became a household name early in his cartooning career, and was soon famous enough to endorse everything from cough drops to cigarettes. By 1931, Rube’s name was in the Merriam-Webster dictionary, his legacy forever cemented as the inventor of complicated machinery designed to perform simple tasks. As one historian put it, Rube’s influence on culture is hard to overstate.
Continue reading “Rube Goldberg’s Least Complicated Invention Was His Cartooning Career”
When [::vtol::] wants to generate random numbers he doesn’t simply type rand() into his Arduino IDE, no, he builds a piece of art. It all starts with a knob, presumably connected to a potentiometer, which sets a frequency. An Arduino UNO takes the reading and generates a tone for an upward-facing speaker. A tiny ball bounces on that speaker where it occasionally collides with a piezoelectric element. The intervals between collisions become our sufficiently random number.
The generated number travels up the Rube Goldberg-esque machine to an LCD mounted at the top where a word, corresponding to our generated number, is displayed. As long as the button is held, a tone will continue to sound and words will be generated so poetry pours forth.
If this take on beat poetry doesn’t suit you, the construction of the Ball-O-Bol has an aesthetic quality that’s eye-catching, whereas projects like his Tape-Head Robot That Listens to the Floor and 8-Bit Digital Photo Gun showed the electronic guts front and center with their own appeal.
Continue reading “Follow The Bouncing Ball Of Entropy”
[Jānis]’s entry for the Flashing Light Prize was doomed from the start. Or should we say Doomed? It was a complicated mess of Rube-Goldbergery that essentially guaranteed that he’d have no time for making a proper video and submitting and entry. But it also ran Doom. Or at least ran on Doom.
(Note: [Jānis] sent us this hack in the e-mail — there’s no link for this blog post. You’re reading it here and now.)
It starts with a DC motor salvaged from a DVD player that spins a wheel that flips a switch back and forth, which in turn flips the polarity of the power on the motor. It’s like a most-useless machine, but with no human involved. This contraption periodically presses a button on a gutted mouse.
Pressing the mouse button on one computer fires a rocket in a multiplayer Doom game, and triggers a light on a wall when it does. A second Doom player, on another computer, sits facing the wall. Solar cells dangled in front of Player 2’s monitor emit high and low voltages as the LCD blinks on and off. That output goes into the ADC of an Arduino clone that drives a transistor that drives a relay that turns on and off a lightbulb.
We had a lot of fun watching all of the entries for the Flashing Light Prize, and we were also stoked by the presence of so many Hackaday regulars in the Honourable Mention list. (Sad to see [Sprite]’s ping-flasher didn’t make the cut!)
If you, like [Jānis] are still sitting on a design, don’t fret. It looks like the prize will make a return next year. Woot!
Continue reading “Doomed Incandescent Light Blinker”
This one was buried in our tips line for a couple of months, but we’re glad it eventually surfaced. [Bob Partington] built the “Rube Slowberg” contraption – it’s billed as the world’s slowest Rube Goldberg Machine. The golf ball that he tee’d off took six weeks to reach it’s rather dramatic end.
Rube Goldberg machines are fascinating, but most often the fun ends quite quickly. [Bob] decided to slow it all down and it took several hacks to get that done. Thankfully for us, the edited video with extensive use of stop-motion and fast forwards brings the chase down to under three minutes.
Check out the video below. It starts with the Golf ball riding a slow boat on molasses, hitching a ride on a Tortoise, running through a series of melting popsicle sticks and then being propelled one tiny bit at a time by a bunch of growing grass. If you are interested is seeing behind the scenes, watch the other video where he talks a little about how he managed to pull it off.
Continue reading “Rube Slowberg”
Throughout their long history, American Machine and Foundry (AMF) have made forays into many areas of automation. And as the American cultural landscape of the 1950s and ’60s shifted toward fast, cheap, and convenient foodstuffs available for consumption inside of spacious, finned automobiles, AMF was there with AMFare, an (almost) completely automated system for taking orders, preparing food, and calculating bills.
AMF named the system “ORBIS” after its two main functions, ordering and billing. But ORBIS was not completely autonomous. A human operator received orders from a table-side telephones inside the restaurant and intercoms used by drive-in customers, and entered them on an enormous console. Orders were routed to several machines to prepare the food, cook it, and package it in various ways. We witness the odyssey of the burger in complete detail, from punching out perfect patties to their final, plastic-wrapped form.
Surprisingly, the AMFare selection wasn’t limited to delicious burgers, fries, and milkshakes. It could crank out sixteen different menu items, and do so pretty quickly. In the space of one hour, AMFare could produce more than 400 burgers, over 350 orders of fries, or about 700 milkshakes. Even so, collating the orders required human intervention. We imagine that the awful task of cleaning all that expensive Rube Goldberg-esque machinery did, too.
Continue reading “Retrotechtacular: Automatic For The People”