Wireless is easier today than ever, with many standards to choose from. But you don’t need anything elaborate if you simply want to cut the cord. A few years back, [Roman Black] experimented with the cheap RF modules you can find on auction sites and from surplus electronics vendors for only a few dollars, and wrote up his findings. They’re well worth a look.
We suppose [Dan Beaven] got up one day and said, “I’ll make my own resin 3D printer, with resin management and an advanced separation mechanism!” It’s a build log that shows just how possible it is to roll your own resin printer.
The machine isn’t finished yet, but the example prints coming off it are already very impressive. [Dan] stopped the print midway to get this photo of the detail on the stairs in the standard rook torture test.
[Dan] wants a lot of features from his machine that some of the more polished commercial printers are only now offering. One really nice one is the sliding and twist separation instead of tilt. This will allow for cleaner separation between layers during a print, a lower failure rate, and also faster print times.
He also added resin management with a peristaltic pump. This reduces the size of the build vat, and less resin will be exposed to the elements and wasted. It also means that the printer can run unattended. In the resin handling area of the printer he’s also added a carbon air filter. This lets him run higher performing resins without gassing him out of house and home with fumes.
We like how [Dan] just runs right ahead and puts the printer together. He even points out kludges on the machine that are holding it together long enough for him to print a more functional part for the 3D printer– on the 3D printer. We look forward to the next installment.
For several decades now all petrol-driven motor vehicles have had to feature a catalytic converter in their exhaust systems to meet the requirements of emissions legislation. These feature a high surface area coated with platinum, palladium, and rhodium, which catalyses the high-temperature breakdown of the exhaust gasses.
When a vehicle reaches the end of its life its catalytic converter is recycled and those metals are recovered, but this recovery does not account for all the metal. [Cody Reeder] noticed that the weight of platinum in a catalytic converter taken from a scrap vehicle is significantly less than that of a new one. Some of that metal has escaped, so where has it gone?
The answer to that question is that it has become detached from the converter and blown out through the rear of the exhaust pipe. Therefore in the area around a busy highway with many thousands of cars passing there must be a reasonable concentration of platinum. The video below the break details [Cody]’s quest to verify that theory, and it opens with him and a friend sweeping dust from beside a freeway in the early hours. The resulting bags contain a lot of gravel and bits of tire, plus a few cigarette butts and a large amount of very fine dust. He sieves away the debris, and heats a sample of dust in a furnace with a flux mixture containing lead oxide. He hopes that as this oxide degrades to metallic lead it will dissolve any platinum and settle in the bottom of his crucible, and indeed when he pours out the resulting slag there is a bead of lead. Taking away the lead reveals a speck of impure platinum, which he further purifies and assays to determine the percentage of platinum and to detect the other catalyst metals.
He finally arrives at a figure of 6.7 g per ton of his fine-sifted roadside dirt “ore”, a figure which as he points out would be considered quite valuable were it to be encountered in a mine. His process might be a little difficult for individuals with sweeping brushes to hit pay dirt and a modern gold rush to descend on their local Interstate, but it’s not impossible that a highways agency equipped with sweeper trucks could have the metal extracted at a more profitable level.
Gerrit and I were scoping out the Intel booth at Bay Area Maker Faire and we ran into Nolan Moore who was showing of his work to mash together a Nintendo Power Glove with an AR Drone quadcopter. Not only did it work, but the booth had a netted cage which Nolan had all to himself to show off his work. Check the video clip below for that.
The control scheme is pretty sweet, hold your hand flat (palm toward the ground) to hover, make a fist and tilt it in any direction to affect pitch and roll, point a finger up or down to affect altitude, and point straight and twist your hand for yaw control. We were talking with Nolan about these controls it sounded sketchy, but the demo proves it’s quite responsive.
The guts of the Power Glove have been completely removed (that’s a fun project log to browse through too!) and two new boards designed and fabbed to replace them. He started off in Eagle but ended up switching to KiCAD before sending the designs out for fabrication. I really enjoy the footprints he made to use the stock buttons from the wrist portion of the glove.
A Teensy LC pulls everything together, reading from an IMU on the board installed over the back of the hand, as well as from the flex sensors to measure what your fingers are up to. It parses these gestures and passes appropriate commands to an ESP8266 module. The AR Drone 2.0 is WiFi controlled, letting the ESP8266 act as the controller.
My heyday in programming was about five years ago, and I’ve really let my skills fade. I started finding myself making excuses for my lack of ability. I’d tackle harder ways to work around problems just so I wouldn’t have to code. Worst of all, I’d find myself shelving projects because I no longer enjoyed coding enough to do that portion. So I decided to put in the time and get back up to speed.
Normally, I’d get back into programming out of necessity. I’d go on a coding binge, read a lot of documentation, and cut and paste a lot of code. It works, but I’d end up with a really mixed understanding of what I did to get the working code. This time I wanted to structure my learning so I’d end up with a more, well, structured understanding.
However, there’s a problem. Programming books are universally boring. I own a really big pile of them, and that’s after I gave a bunch away. It’s not really the fault of the writer; it’s an awkward subject to teach. It usually starts off by torturing the reader with a chapter or two of painfully basic concepts with just enough arcana sprinkled in to massage a migraine into existence. Typically they also like to mention that the arcana will be demystified in another chapter. The next step is to make you play typist and transcribe a big block of code with new and interesting bits into an editor and run it. Presumably, the act of typing along leaves the reader with such a burning curiosity that the next seventeen pages of dry monologue about the thirteen lines of code are transformed into riveting prose within the reader’s mind. Maybe a structured understanding just isn’t worth it.
I wanted to find a new way to study programming. One where I could interact with the example code as I typed it. I wanted to end up with a full understanding before I pressed that run button for the first time, not after.
When I first read about literate programming, my very first instinct said: “nope, not doing that.” Donald Knuth, who is no small name in computing, proposes a new way of doing things in his Literate Programming. Rather than writing the code in the order the compiler likes to see it, write the code in the order you’d like to think about it along with a constant narrative about your thoughts while you’re developing it. The method by which he’d like people to achieve this feat is with the extensive use of macros. So, for example, a literate program would start with a section like this:
Continue reading “Learn To Program With Literate Programming”
For this year’s Hackaday Prize, we’re doing something spectacular. We’re funding the next great piece of Open Hardware by giving away thousands of dollars for the best hardware projects. Just a few days ago, we wrapped up the Anything Goes portion of The Hackaday Prize, an electronic free for all to build the coolest gizmos imaginable. Now, it’s time to announce the twenty winners of the Anything Goes portion of The Hackaday Prize.
The winners of the Anything Goes challenge, in no particular order, are:
These twenty project just won $1000 and will now move on to the last phase of The Hackaday Prize, to be judged by our fourteen celebrity judges. Congrats! There’s a lot of work for these project to do before the final judging in October. Better get to work!
If your project didn’t make the cut, there’s still ample opportunity for you to build the next great hardware gizmo. For the next few weeks, we’re running the Citizen Scientist portion of The Hackaday Prize. We’re looking for projects that expand the frontiers of knowledge, and give the common man the tools to discover the world.
Citizen Scientist is this month’s Hackaday Prize challenge to create something new, study something undiscovered, or replicate scientific studies. We’re opening up the gates for everyone to build their own apparatus and do their own research.
Like the Design Your Concept and Anything Goes rounds of The Hackaday Prize, the top twenty projects will win $1000, and go on to the Hackaday Prize finals for a chance to win the Hackaday Prize – $150,000 and a residency at the Supplyframe Design Lab in Pasadena.
If you don’t have a project up on Hackaday.io, you can start one right now and submit it to The Hackaday Prize. If you already have a project up, add it to the Citizen Scientist challenge using the dropdown menu on the left sidebar of your project page.
Artists see the same world that the rest of us do. They just see it from a little bit off to the left. Where you see picking an ESSID for your router as being a hassle, or an opportunity to insult your neighbors, [Dmitry], alias [::vtol::] sees a poetry-delivery mechanism.
Based on ESP8266 units, each “poet” has a battery and a switch. Turn it on and it changes its SSID once every ten seconds, feeding everyone who’s listening the next line of a poem. You can’t connect to the network, but you can occasionally hit refresh on your WiFi scanner and read along.
Since they’re so cheap to build, [::vtol::] sees them almost as if they were poetry-throwies. You could easily afford to leave a few around the city, guerilla-style, broadcasting your (slow) message one SSID at a time. We love the video clips (inlined below) of him riding the subway with the device on.
