An automatic color mixer, dispensing a mixture of red and yellow

The M5Stack Color Maker Can Mix Paint To Match Your Subject

October 11, 2021 by Robin Kearey 28 Comments

We’ve all learned in primary school art classes that blue and yellow make green, and that adding a little black to a color will make it darker. But what if you want to paint with a color that exactly matches something else? Usually, that requires a lot of trial and error (and paint), and the end result may not look the way you wanted after all.

To help aspiring artists, [Airpocket] made the M5Stack Color Maker. This is a device that reads out a color sensor and automatically mixes watercolor paint in the right proportions to match what it sensed. It dispenses drops of cyan, magenta, yellow and black paint (CMYK) into a small bowl, from which you can then apply it with a paintbrush.

The color sensor is similar in use to the color picker (or “dropper”) tool present in most graphics programs: simply point it at something that has the right color, and it will generate the correct values for you. It is based on an AMS TCS34725 color sensor, which is housed in a 3D-printed shell that also includes a white LED. The sensor outputs Red, Green and Blue (RGB) values, which are converted into the corresponding CMYK values by a Raspberry Pi Pico. A touch-sensitive screen allows the user to make adjustments before activating the paint pumps.

Those pumps are tube pumps, which have been specifically designed (and also 3D printed) to allow them to move tiny amounts of liquid while minimizing the pulsing motion typical with this type of pump. They are driven by stepper motors which are controlled by the Pi Pico.

Although many artists might prefer to mix their colors manually, the M5Stack makes mixing that exact shade of blue just that little bit easier. We can also imagine it might help those who are color blind and unable to clearly tell different colors apart. We’ve seen simple paint mixers for larger quantities of paint, and even robots that can do the actual painting for you. If you need a refresher on color theory, we’ve got you covered too.
Continue reading “The M5Stack Color Maker Can Mix Paint To Match Your Subject” →

Putting M5Stack On LoRa And The Things Network

September 29, 2018 by Eric Evenchick 4 Comments

LoRa is the new hotness in low-power, long-range communications. Wanting to let the packets fly, [Xose] was faced with a frequecny problem and ended up developing a Europe-friendly LoRa module for the M5Stack system. The hardware is aimed at getting onto The Things Network, a LoRa based network that provides connectivity for IoT devices. While there was an existing M5Stack module for LoRa, it only supported 433 MHz. Since [Xose] is in Europe, an 868 MHz or 915 MHz radio was needed. To solve this, a custom board was built to connect the HopeRF RFM69 series of modules to the M5Stack.

If you haven’t heard of it before, the M5Stack platform is a stackable development board platform. Like Arduino, you can add functionality by stacking PCBs using a standard header. Unlike Arduino, M5Stack fits in a case nicely and is designed for building devices with user interfaces. For $35, you get an ESP32 based system with WiFi, Bluetooth, a color LCD, battery, buttons, a speaker, and IO connectors.

With the hardware in place, [Xose] 3D printed a custom case to hold the board and added it to the stack. The firmware acts as a monitor for The Things Network, showing live coverage. The final product looks very clean for a prototype, maintaining the finished look of M5Stack.

The firmware, board design, and case design files for the project are all available on Github.

A Simple Laser Harp MIDI Instrument

June 19, 2024 by Dave Rowntree 5 Comments

Craig Lindley is a technical author and a prolific maker of things. This simple project was his first attempt to create a laser harp MIDI device. While on vacation, Craig saw a laser harp with only three strings and decided to improve upon it by expanding it to twelve strings. The principle of operation is straightforward: twelve cheap diode laser modules aim a beam towards an LDR, which changes resistance if the light level changes when the beam is interrupted.

The controller is a simple piece of perf board, with a Wemos D1 mini ESP32 module flanked by some passives, a barrel socket for power, and the usual DIN connector for connecting the MIDI instrument. Using the ESP32 is a smart choice, removing all the need for configuration and user indication from the physical domain and pushing it onto a rarely-needed webpage. After a false start, attempting to use a triangular frame arrangement, [Craig] settled upon a simple linear arrangement of beams held within a laser-cut wooden box frame. Since these laser modules are quite small, some aluminium rod was machined to make some simple housings to push them into, making them easier to mount in the frame and keeping them nicely aligned with their corresponding LDR.

Sadly, the magnetic attachment method [Craig] used to keep the LDRs in place and aligned with the laser didn’t work as expected, so it was necessary to reach for the hot glue. We’ve all done that!

An interesting addition was using an M5 stack Unit-Synth module for those times when a proper MIDI synthesiser was unavailable. Making this luggable was smart, as people are always fascinated with laser harps. That simple internal synth makes travelling to shows and events a little easier.

Laser harps are nothing new here; we have covered plenty over the years. Like this nice build, which is more a piece of art than an instrument, one which looks just like a real harp and sounds like one, too, due to the use of the Karplus-Strong algorithm to mimic string vibrations.

Open Source Scanner Scans The Slides

December 26, 2023 by Al Williams 9 Comments

What do you get when you join a slide projector and a digital camera? Filmolimo, an open source slide scanner. The scanner uses an M5Stack Fire, an ESP32 development board. Thanks to the ESP32, you can control the device via WiFi.

All the project files, including KiCAD design files, are on GitHub. Of course, you will probably have to adapt things to your specific camera and slide projector. The PCB is double-sided and looks easy to put together. The board is mostly opto-isolation and interface between the controller and the equipment. The software allows you to change things like the time between slides, for example.

This is one of those projects you probably only need for a bit. Unless, of course, you regularly scan slides. You can farm it out to a service provider, but what fun is that? If you have a few hundred thousand slides, you might need to go for speed. If you just have a few, you can get by with a simple adapter.

Illuminated smart curtain in front of a window, beside a Christmas tree

Smart LED Curtain Brings Sprites To Your Windows

January 14, 2023 by Dave Walker 13 Comments

Mobile interface for LED smart curtain display — A mobile interface is a nice touch

Anybody who has ever seen a video wall (and who hasn’t?) will be familiar with the idea of making large-scale illuminated images from individual coloured lights. But how many of us have gone the extra mile and fitted such a display in our own homes? [vcch] has done just that with his Deluxe Smart Curtain that can be controlled with a phone or laptop.

The display itself is made up of a series of Neopixel strips, hung in vertical lines in front of the window. There is a wide gap between each strip, lending a ghostly translucent look to the images and allowing the primary purpose of the window to remain intact.

The brains of the system are hosted on a low-cost M5stack atom ESP32 device. The data lines for the LEDs are wired in a zig-zag up and down pattern from left to right, which the driver software maps to the rectangular images. However, the 5V power is applied to the strips in parallel to avoid voltage drops along the chain.

If you’d like to build your own smart curtain, Arduino sketch files and PHP for the mobile interface are included on the project page. Be sure to check out the brief video of what the neighbors will enjoy at night after the break.

If video walls are your kind of thing, then how about this one that uses Ping Pong Balls as diffusers? Continue reading “Smart LED Curtain Brings Sprites To Your Windows” →

2022 Cyberdeck Contest: RPG Character Tracker

September 14, 2022 by Tom Nardi 7 Comments

While it would be a mistake to think there are any firm rules for what constitutes a cyberdeck, we can at least identify some common traits that would seem to give us a baseline description. For example, most deck builds we’ve seen have been fully-functional Linux computers, more often than not powered by some Raspberry Pi variant. But that doesn’t mean there isn’t room in the community for less computational powerful decks, or builds that are so bespoke that they can only perform a few selected tasks.

As a perfect example, take a look at the RPG Character Tracker from [Melissa Matos]. You won’t find a Raspberry Pi here, nor a full operating system. Instead, we’ve got a M5Stack Core2 and an I2C CardKB Mini Keyboard wrapped up in a foldable frame made from Erector Set pieces. Add in a little LED lighting for that cyberpunk feel, and the stage is set.

So what does this diminutive build do? Well, apparently nothing right now. [Melissa] just got the hardware together and has only recently started aligning all the 1s and 0s to do her bidding. But what it’s supposed to do is clear enough: it’s intended to be an electronic companion to complex RPG tabletop games to help with things such as character creation. Sounds like it will also have a “roll dice” mode that will save you the trouble of having to crawl under the table when one of your D20s goes rogue.

While such a device could be useful for many different games, it should come as no surprise to hear that [Melissa] is currently targeting the cyberpunk Shadowrun.

Although we were particularly taken with the online tool that let you generate 3D printed organizers for all your tabletop gaming needs, we’d definitely rather have digital companions like this which would make those plastic baggies full of parts obsolete.

FlowIO Takes Top Honors In The 2021 Hackaday Prize

November 20, 2021 by Dan Maloney 8 Comments

FlowIO Platform, a modular pneumatics controller for soft robotics and smart material projects, took home Grand Prize honors at the 2021 Hackaday Prize. Aside from the prestige of coming out on top of hundreds of projects and bragging rights for winning the biggest hardware design challenge on Earth, the prize carries an award of $25,000 and a Supplyframe DesignLab residency to continue project development. Four other top winners were also announced at the Hackaday Remoticon virtual conference on Saturday evening.

In a year full of challenges, this year’s Hackaday Prize laid down yet another gauntlet: to “Rethink, Refresh, and Rebuild.” We asked everyone to take a good hard look at the systems and processes that make the world work — or in some cases, not work — and reimagine them from a fresh perspective. Are there better ways to do things? What would you come up with if you started from a blank piece of paper? How can you support and engage the next generation of engineers, and inspire them to take up the torch? And what would you come up with if you just let your imagination run wild?

And boy, did you deliver! With almost 500 entries, this year’s judges had quite a task in front of them. Each of the five challenges — Refresh Displays, Rethink Work-From-Home Life, Reimagine Supportive Tech, Redefine Robots, and Reactivate Wildcard — had ten finalists, which formed the pool of entries for the overall prize. And here’s what they came up with.

Continue reading “FlowIO Takes Top Honors In The 2021 Hackaday Prize” →