Machine Extrudes Filament

July 4, 2021 by 28 Comments

We’ve seen a lot of homebrew filament extruders, but [Stefan] at CNC Kitchen shows off a commercial desktop filament extruder in his latest video, which you can see below. The 3DEVO extruder is pretty slick but at around $7,000-$8,000 we probably won’t rush out and buy one. We might, though, get some ideas from it for our next attempt to build something similar.

In concept, any machine that creates filament is pretty straightforward. Melt pellets and push them out of a nozzle. Cool the filament and wind it up. Easy, right? But, of course, the problems are all in the details. Die swell, for example, means you can’t just assume the nozzle’s hole size will give you the right size filament. Continue reading “Machine Extrudes Filament” →

Vintage Remote Control Gets Bluetooth Upgrade

July 4, 2021 by 20 Comments

This swanky Magnavox remote is old enough to predate the use of infrared, and actually relies on ultrasound to communicate with the television. It’s a neat conversation starter, but not terribly useful today. Which is why [Chad Lawson] decided to gut the original electronics and replace it with a Adafruit Feather 32u4 Bluefruit LE that can actually talk to modern devices.

We know, we know. Some in the audience will  probably take offense to such a cool gadget being unceremoniously torn apart, but to be fair, [Chad] does say he has a second one that will remain in its original state. Plus a quick check on eBay shows these old remotes don’t seem to be particularly rare or valuable. In fact, after some browsing through the recently concluded auctions, we’re fairly sure he paid $27 USD for both of these remotes.

Anyway, [Chad] found that a piece of perfboard in his collection just happened to be nearly the same size as the PCB from the remote, which made the rest of the conversion pretty straightforward. He simply had to mount tactile switches on one side of the perfboard so the remote’s original buttons would hit them when pressed, and then wire those to the Adafruit on the other side. We know there’s a 3.7 V 500 mAh pouch battery in there someplace as well, though it’s not immediately clear where he hid it in the images.

The code [Chad] came up with tells the Adafruit to mimic a Bluetooth Human Interface Device (HID) and send standard key codes to whatever device pairs with it. That makes it easy to use as a media remote on the computer, for example. We’ve seen something similar done with the ESP32, if you’ve already got one in the parts bin and are looking to revamp a remote control of your own.

At the end of the write-up, [Chad] mentions he may try developing an ultrasonic receiver that can pick up the signals from the unmodified remote control. That would be a nice way to bring this whole thing full circle, and should appease even the most hardcore vintage remote control aficionados.

This Arduino Isn’t Color Blind

July 4, 2021 by 5 Comments

You can sense a lot of things with the right sensor, and [Nikhil Nailwal] is here to show us how to sense colors using a TCS230. The project is a simple demo. It displays the color and lights up an LED to correspond to the detected color.

If you haven’t seen the TCS230 before, it is a chip with an array of photosensors, for different light wavelengths. The controlling chip — an Arduino, in this case — can read the intensity of the selected color.

Continue reading “This Arduino Isn’t Color Blind” →

Extreme Canine Mask For Protection From Foxtails

July 4, 2021 by 33 Comments

Our canine partners are fortunately not affected by the current global pandemic, but it turns out there are other dangers that might necessitate them to wearing masks: Foxtail seeds. After getting a $400 vet bill for extracting a foxtail from his dog, [Hildeguard]’s ear, [Amos Dudley] decided to take the threat seriously and made her a form-fitting 3D printed mask.

The only commercial solution [Amos] could find was the “OutFox Field Guard”, which is a $50 vinyl-coated mesh bag that covers the dog’s entire head. It had the unfortunate side effects of causing some other dogs to try and rip it off and does not allow easy access to the mouth for treats or balls. [Hilde]’s custom mask was designed in CAD after creating a rough 3D scan of her head with an iPhone app. The bottom is open to allow [Hilde] to freely use her mouth, while the nose and ears holes are covered with mesh. Custom heat-formed polycarbonate lenses cover the eye holes. The mask itself was printed using Draft resin, and the inside was padded with a thin layer of foam. It might also be possible to create a silicone version using a 3D-printed mold. The top features an integrated GoPro mount, and we can’t help but wonder what other electronic upgrades could be fitted to this sci-fi-looking mask.

In the field, the mask worked well and did not seem to bother [Hilde]. Unfortunately, it did not solve the problem of other dogs trying to rip it off at the park, so for the moment [Amos] is only using it for more solitary activities like hiking.

It doesn’t look like [Amos] is struggling in that department, but if you need some help burning of your dog’s energy, you can always built them a 3D printed automatic ball launcher.

 

Internet Chess On A Real Chessboard

July 3, 2021 by 5 Comments

The Internet teaches us that we can accept stand-ins for the real world. We have an avatar that looks like us. We have virtual mailboxes to read messages out of make-believe envelopes. If you want to play chess, you can play with anyone in the world, but on a virtual board. Or, you can use [karayaman’s] software to play virtual games on real boards.

The Python program uses a webcam. You point it at an empty board and calibrate. After that, the program will track your moves on the real board in the online world. You can see a video of a test game below.

Continue reading “Internet Chess On A Real Chessboard” →

Hacking Old Honda ECUs

July 3, 2021 by 21 Comments

Automotive security specialist by day [P1kachu] hacks his own cars as a hobby in his free time. He recently began to delve into the Engine Control Units (ECUs) of the two old Hondas that he uses to get around in Japan. Both the 1996 Integra and the 1993 Civic have similar engines but different ECU hardware. Making things more interesting; each one has a tuned EPROM, the Civic’s being of completely unknown origin.

[P1kachu] took his Civic to a shop to have some burned-out transistors replaced in the ECU, and a chance conversation with the proprietor [Tuner-san] sends him on a journey into the world of old EPROMs. [Tuner-san] pulled out an old PROM duplicator stashed away under the counter which he originally used as a kid to copy PROM chips from console games like the Famicom. These days he uses it to maintain a backup collection of old ECU chips from cars he has worked on. This tweaked [P1kachu]’s curiosity, and he wondered if he could obtain the contents of the Civic’s mysterious PROM. After a false start trying to use the serial port on the back of the PROM copier, he brute-forces it. A few minutes of Googling reveals the ASCII pinout of the 27C256 EPROM, and he whips out an Arduino Mega and wires it up to the chip and is off and running.

Advantest R4945A EPROM Duplicator c.1980s

He’s currently digging into the firmware, using IDA and a custom disassembler he wrote for the Mitsubishi M7700 family of MCUs. He started a GitHub repository for this effort, and eventually hopes to identify what has been tweaked on this mysterious ECU chip compared to factory stock. He also wants to perform a little tuning himself. We look forward to more updates as [P1kachu] posts the results of his reverse engineering efforts. We also recommend that you be like [P1kachu] and carry an Arduino, a breadboard, and some hookup wire with you at all times — you never know when they might come in handy. Be sure to checkout our articles about his old Subaru hacks from in 2018 if these kinds of projects interest you.

E-Ink Equipped Sourdough Starter Jar

July 3, 2021 by 2 Comments

One of the unexpected side effects of our this pandemic is a sudden growth in the global population of captive colonies of Lactobacillus bacteria and yeast. Also known as sourdough starters, they are usually found in jars with curious names written on top, living off a mixture of flour and water. They require close monitoring to keep them healthy and to determine when they are ready for baking. [Noah Feehan] has been working to instrument and automate the process for the past two years, and has created a high-tech jar to keep an eye on his sourdough starter.

For a sourdough starter to stay active, it must be kept within a certain temperature range, and performance is measured by how much the level inside the jar rises. Existing open source and commercial projects monitor these two parameters and transmit data out, but [Noah] wanted to include a few more features. The height of a sourdough starter rises due to the production of CO2, so he added an SCD-30 sensor module, which includes a temperature and humidity sensor. For level monitoring, an VL6180 time-of-flight sensor is mounted over a hole on top of the jar. [Noah] wanted to be able to see recent CO2 production and height stats right on the jar, a ESP32 module with onboard E-ink display was used. To draw air over the CO2 sensor at a constant rate, a small extraction fan was also added. Power is provided by a small LiPo battery. For long term logging, the data is sent over MQTT to a server running Mycodo environmental regulation software.

There are still several software improvements [Noah] would like to make, including battery life, user interface and alerts, but everything is open-source and available on GitHub, so feel free to jump in and build your own.