Posts

Featured Post

Fat Tire Brakes Get Wireless Upgrade

-
Image
At first glance, wireless brakes seem like a recipe for disaster. For something as critical as braking, many bicyclists might prefer a physical connection to their method of safely controlling speed. But there are a number of surprising benefits of electronic or wireless braking systems. For one, they can enable systems like anti-lock braking systems and for another they can eliminate cabling or hydraulics on a bicycle. For these reasons, and just for the thrill of it, [Berm Peak] built a set of wireless brakes for his fat tire bicycle to test out the possibilities. The system uses a set of ESP32 microcontrollers to handle inputs from the braking lever and outputs to the front and rear brakes, as well as a central control unit and display. The brakes themselves are controlled by actuators from car door locks, which when combined with the springs from the stock calipers work to apply a wide range of braking force to the wheels. These did take a bit of prototyping to get working right,...
Post a Comment
Get this one»

Compact PCB Vise Uses Up That Leftover Filament

-
Image
Needing less than 70 grams of filament, [Chefkoch]’s 3D printed PCB vise solder station might be a good way to use up some filament spool leftovers and get yourself a handy tool in return. What we like about this design is that it is multi-functional, and cleverly uses the solder spool as a counterweight to add stability that might otherwise be lacking in such a compact design. The assembly can be reconfigured so that the jaws are either horizontal or vertical; the solder spool is held conveniently either way. The whole thing is 3D printed, so there’s no other hardware or fasteners involved. It’s probably best suited to small boards, but it’s also compact, entirely 3D printed, and doesn’t need much filament. Still have some filament left over and want a nifty solder feeder to go with it? Check out the solder scroll , a pen-like DIY tool that makes handheld solder feeding a little less of a hassle. from Blog – Hackaday https://ift.tt/u0gkoEO
Post a Comment
Get this one»

Wikipedia on a Cheap Yellow Display

-
Image
The Cheap Yellow Display (CYD) is a board carrying a slightly older ESP32 variant, a display with a resistive touchscreen, an SD card, and not much else. It’s often used for straightforward microcontroller applications that need a user interface, but that’s not the limit of its possibilities. [Alun Morris] has a CYD on which you can brows an entire offline Wikipedia . The trick is to take the offline Wikipedia builds from the Kiwix project, and process them further into a custom format suited for a browser firmware on the ESP32. A modern SD card can hold so much data that a full Wikipedia is well within its abilities even with images included. We like this idea, because it takes the knowledge away from the center of the network to its edge. We expect to see it gaining a following among enthusiasts for offline living, because all that knowledge without a network can only be useful. If you recognize [Alun]’s work, it might be because of his ESP32 web browser . from...
Post a Comment
Get this one»

This Library Needs to Be At Least… Three Times Bigger

-
Image
Many of us have noted a tremendous price increase in many computer components for some mysterious reason. Whatever this cause is will be debated among the various modern philosophers and Diogeneses, but regardless of cause we all still have to live in this world and make do. That turns us towards getting maximum value from the things we already have rather than trying to go out and buy more computer components right now, like [svofski] using his vast swath of existing microSD cards to build an SD card library . The library is based around a tiny robotic arm that can physically grip the cards and move them in and out of a reader. The first iteration of the arm involved rotating the two pincers, but this turned out to be overly complicated and [svofski] eventually settled on a design resembling a rack and pinion that slides the two pincers together instead. With the gripper sorted out, it’s placed in system called T-bot arrangement, similar to coreXY kinematics, that lets it pick a...
Post a Comment
Get this one»

Reviving an SD Card With Shorted Capacitors

-
Image
Tiny capacitors in an SD card package. (Credit: Aeson Labs) A nice thing about SD cards is that even in their non-micro format they are conveniently small. This is however a bit of a problem when an SD card stops working, as they are not exactly designed to be easy to service, or to recover data from. There is however a very good chance that the Flash memory and controller are still fine, and it’s actually one of the passives on the tiny PCB that failed, as with the 32 GB SD card that [Yevgeniy Kapishon] recently diagnosed and recovered data from for a customer. A big hint during initial diagnostics was a clear short between the supply rail and ground, but as became clear when taking the SD card apart, this one was built as a monolithic package, without exposed components on a PCB as in older SD cards. Correspondingly an X-ray machine and thermal camera were used to figure out what was inside the package, and where the short was located. By combining the hot spot image with th...
Post a Comment
Get this one»

DOOM Played on Series of 555 Timers

-
Image
It’s technically true that any piece of software can be reproduced in hardware, although modern software’s size and complexity generally makes this a non-starter. But if we go far enough back in time, older software becomes easier and easier to implement in hardware. The original DOOM from 1993 might one day be recreated in full this way, but that day is not today. Instead, [Nick] has recreated the original music from that game, playing the opening track in nothing but 555 timers . The circuit starts with a 555 timer that acts as a system clock with a rate of just over 7 Hz. These pulses feed a binary counter which in turn feeds a decoder, giving the circuit 15 positions. Each output of the decoder feeds to a diode matrix which stores information about what pitch the circuit should play. The circuit only needs to play six pitches so the diodes effectively connect each moment in time to one of these six notes. From there the circuit feeds into a set of switches which select ...
Post a Comment
Get this one»

Casting Engine Parts from 3D Prints

-
Image
After building a couple of internal combustion engines by milling billet aluminium stock and cringing at the absolute waste of material this created, [Camden Bowen] figured he’d give casting metal parts a shot . Of course, the key here is to create the molds for said casting, which is where you got a few options available. Since DIY is really his thing, he also made his own kiln using cement and perlite, plus a propane burner. For the aluminium material to melt, he bought a stack of aluminium alloy wheels, as these are made of an alloy that’s actually suitable for casting. These were turned into ingots as a first step towards casting the engine parts, which among other things helps to purify the metal. For the actual casting method he picked lost PLA, meaning the intended shape is 3D printed in PLA, then put into plaster before it’s melted out of the newly minted mold in an oven and subsequently burned out in the kiln. For the plaster [Camden] used regular Plaster o...
Post a Comment
Get this one»