Fluidized Bed In A Pringles Can Paints Parts Inside And Out

November 3, 2021 by Adam Zeloof 12 Comments

Powder coating is a wonderful way to apply a smooth, colored surface to a part, whether for aesthetic reasons or corrosion protection. Traditionally, powder is applied via a air gun that sprays it towards a part while giving the grains an electrostatic charge. The part to be coated (generally metal) is hanging on a rack and given an opposite charge, and the powder readily flows to the surface and sticks well. The dry coated part is then placed in an oven which melts the powder into a solid, continuous surface. The main drawback of the process is that while simple parts with large surfaces are easy to coat, it can become difficult to get powder to flow evenly into deep crevices, or inside a hollow part such as a tube.

Enter fluidized bed powder coating — a process in which air shoots through a vat of powder, making it move like a fluid. A heated part can be dipped inside the vat, instantly melting a thin layer of powder around the part. This much simpler method is great at getting inside all those pesky crevices that traditional coating can’t touch, and hacker [Amper] was able to build a custom fluidized bed coater in a Pringles can. This rendition, inspired by this video tour of Dan Gelbart’s workshop, uses a coffee filter to evenly distribute the air flow supplied by a small compressor — [Amper] quickly learned that just sticking a tube in a bucket of powder results in more of a volcano than a nice, fluid surface. A burner heated up some pieces of metal that were then dipped them in the can, resulting in complete coverage, even inside the tiny 5 mm diameter hole down the center of a piece of 80/20 extrusion. Once [Amper] got the basic idea working, the idea scaled up into a larger machine that you can check out in the video below.

Powder coating is usually one of those processes though of as only viable in professional shops, but [Amper] along with some other intrepid hackers have done a great job demonstrating that it can be possible for the rest of us too. We’ve even seen some others experiment with fluidized bed coating before — it’s always great to see a process such as this one gradually become more and more accessible.

Thanks to [mip] for the tip!

Continue reading “Fluidized Bed In A Pringles Can Paints Parts Inside And Out” →

Keep Calm And Hack On: The Philosophy Of Calm Technology

November 3, 2021 by Michael Shaub 44 Comments

So much smart-tech is really kind of dumb. Gadgets intended to simplify our lives turn out to complicate them. It often takes too many “clicks” to accomplish simple tasks, and they end up demanding our attention. Our “better mousetraps” end up kludgy messes that are brittle instead of elegant and robust.

The answer might not be faster or newer technology, but a 30-year-old philosophy. Some great thinkers at Xerox PARC, the place where, among other things, the computer mouse was invented, developed principles they called Calm Technology.

Continue reading “Keep Calm And Hack On: The Philosophy Of Calm Technology” →

Here Are The Ten Finalists For The Hackaday Prize Wildcard Challenge

November 3, 2021 by Tom Nardi No comments

Each phase of the 2021 Hackaday Prize challenged designers to reimagine traditional solutions within various fields, from robotics to assistive devices. But for the Reactivate Wildcard, the fifth and final Challenge of this year’s Prize, this theme of Rethink, Refresh, Rebuild could be applied on anything the entrant wanted. Today we’re pleased to announce the ten Wildcard projects that have been selected to win $500 and move onto the finals. Who will win the top spot this year? We’ll find out during Hackaday Remoticon in just a few weeks!

The MetaSense project is a perfect example of how new technology can be used to rethink what we generally consider to be a solved problem. This project leverages multi-material 3D printing to produce conductive cells which vary their capacitance in response to physical deformation. With some clever geometry, these cells can be chained together to produce single-part devices which can stand in for traditional toggle switches, joysticks, pressure sensors, and even accelerometers.

Speaking of 3D printing, the Direct Granules Extruder project imagines a future were desktop printers are no longer limited to using rolls of manufactured filament. The key is a robust extruder design that can grind up plastic pellets fast enough to feed them directly into the hotend of a conventional 3D printer. This not only means a considerable operational savings, as raw plastic pellets are much cheaper than filament by weight, but would potentially allow for printing with more exotic plastic blends and even recycled materials.

Some of the projects even made us rethink what’s possible for the individual hacker. The WiFiWart utilizes a miniature single-board Linux computer that was designed and built from the ground up by a single person, using only free and open source software. Whether it’s that this penetration testing gadget has packed a full Linux computer and two WiFi adapters into a box the size of a phone charger, or the fact that it’s been done by a dedicated hacker with free tools, you can’t help but come away impressed with this one.

Wild For Wildcard

With nearly 100 projects submitted for the Reactivate Wildcard challenge, this was clearly a theme that resonated with the Hackaday community. As always, it was extremely difficult to narrow this down to the ten finalists below:

Whether or not they made the Finals this year, the complete list of Reactivate Wildcard entries contains an incredible array of fascinating concepts that are well worth browsing through. If any of them particularly catch your eye, why not strike up a conversation with the creator in the comments and see if you can’t help out? There’s always next year.

Simplify 3D Printer Wiring With CAN Bus

November 3, 2021 by Dave Rowntree 56 Comments

[mark] had an interesting idea when looking at all the wiring of a typical 3D printer; Use CAN Bus. There are a lot of wires going to the extruder assembly, and with most designs this thing is flying around at quite some speed. You’ve got connections for powering the heater, fan power, four wires for the extruder motor, thermistor sensor wires. You get the idea. Lots of wires. Worse, they’re all moving around with the axis, and if failures occur at either end due to poor strain relief, or the conductors themselves break, then all manner of interesting failures can occur. If the hot end thermistor connection goes open circuit, usually no damage occurs but the temperature control goes out the window and your print will fail.

Now if you push the electronics needed to drive and control the extruder, directly onto the moving body itself, and hook-up to the main printer electronics with CAN Bus, you can do the whole moving interconnect thing with a measly four wires. Yes, you need another PCB assembly, so it adds cost, but it does also simply the electronics at the control end, so some savings can be made. [mark] has used CAN Bus due its availability with modern microcontrollers and also its designed-in robustness, thanks to its automotive and industrial heritage. When you think about it, this is a rather obvious thing to do, and we’re not sure why we’ve not see it much before.

If you want to dig into the detail, the project GitHub has the schematics and code ready to go.

Continue reading “Simplify 3D Printer Wiring With CAN Bus” →

Python Ditches The GILs And Comes Ashore

November 3, 2021 by Matthew Carlson 38 Comments

The Python world has been fractured a few times before. The infamous transition from version 2 to version 3 still affects people today, and there could be a new schism in the future. [Sam Gross] proposed a solution to drop the Global ~~Interrupt~~ Interpreter Lock (GIL), which would have enormous implications for many projects that leverage the CPython internals, such as Pandas and NumPy.

The fact that Python is interpreted is a double edge sword. It means there can be different runtimes, such as Pyston, Cinder, MicroPython, PyPy, and others, that might support the whole language, a specific version, or a subset. But if you’re using Python, you’re probably running CPython. And it has something known as global interpreter lock that affects threaded code. In a nutshell, only one thread can run in the interpreter at a time. There are some ways around it, such as moving performance-critical sections to C or having multiple interpreters. However, most existing solutions come with considerable downsides. Continue reading “Python Ditches The GILs And Comes Ashore” →

[Nick Rehm] explains the workings of a gps-less self guided drone

Autonomous Drone Dodges Obstacles Without GPS

November 3, 2021 by Ryan Flowers 5 Comments

If you’re [Nick Rehm], you want a drone that can plan its own routes even at low altitudes with unplanned obstacles blocking its way. (Video, embedded below.) And or course, you build it from scratch.

Why? Getting a drone that can fly a path and even return home when the battery is low, signal is lost, or on command, is simple enough. Just go to your favorite retailer, search “gps drone” and you can get away for a shockingly low dollar amount. This is possible because GPS receivers have become cheap, small, light, and power efficient. While all of these inexpensive drones can fly a predetermined path, they usually do so by flying over any obstacles rather than around.

[Nick Rehm] has envisioned a quadcopter that can do all of the things a GPS-enabled drone can do, without the use of a GPS receiver. [Nick] makes this possible by using algorithms similar to those used by Google Maps, with data coming from a typical IMU, a camera for Computer Vision, LIDAR for altitude, and an Intel RealSense camera for detection of position and movement. A Raspberry Pi 4 running Robot Operating System runs the autonomous show, and a Teensy takes care of flight control duties.

What we really enjoy about [Nick]’s video is his clear presentation of complex technologies, and a great sense of humor about a project that has consumed untold amounts of time, patience, and duct tape.

We can’t help but wonder if DARPA will allow [Nick] to fly his drone in the Subterranean Challenge such as the one hosted in an unfinished nuclear power plant in 2020.

Continue reading “Autonomous Drone Dodges Obstacles Without GPS” →

Liberating The ESP8266 From Its Development Board

November 3, 2021 by Tom Nardi 14 Comments

While the ESP32 is clearly a superior piece of hardware, we think you’ll agree that the ESP8266 is just too useful not to have a dozen or so kicking around the parts bin at any given time. Cheap, easy to use, and just enough capabilities to bring your projects into the wonderful world of IoT. But if you really want to get the most out of it, you’ll eventually have to skip the development board and start working with the bare module itself.

It can be a scary transition, but luckily, [Ray] has collected some notes that should prove helpful for anyone looking use modules like the ESP-12F in their own custom PCBs. From different tips on making sure the power-hungry modules get enough juice, to cost cutting measures that help reduce the ancillary parts needed in your circuit design, it’s a worthwhile read for new and experienced ESP8266 wranglers alike.

For example, [Ray] talks a bit about using the infamous GPIO10 pin. This pin is on the rear of the ESP8266 module, and on many development boards, it isn’t even connected. That’s because its internally hooked up to the ESP8266’s SPI flash chip, and using it can cause problems if you’re not careful. But as explained in the blog post, as long as you make sure the flash mode is set to “dual IO” (DIO), then GPIO10 can be used just like any other free pin.

We also really liked the tip [Ray] shares at the end for making your boards more easily programmable. Sure you can leave an unpopulated header on the board, or fiddle with some pogo pin setup, but his edge connector approach is quite clever. Just slip the programmer on for the initial burn, and then after that you can update over the air.

There’s no denying how easy it is to throw something together with an ESP8266 development board, but we’ve covered so many incredible projects that have made use of the bare module’s diminutive dimensions that you’ll ultimately be missing out if you don’t cut out the middle-man.