Tag Archives: wireless

Encased in amber: meet the epoxy-embedded Pi

via Raspberry Pi

The maker of one of our favourite projects from this year’s Maker Faire Bay Area took the idea of an ’embedded device’ and ran with it: Ronald McCollam has created a wireless, completely epoxy-encased Pi build – screen included!

Resin.io in resin epoxy-encased Raspberry Pi

*cue epic music theme* “Welcome…to resin in resin.”

Just encase…

Of course, this build is not meant to be a museum piece: Ronald embedded a Raspberry Pi 3 with built-in wireless LAN and Bluetooth to create a hands-on demonstration of the resin.io platform, for which he is a Solution Architect. Resin.io is useful for remotely controlling groups of Linux-based IoT devices. In this case, Ronald used it to connect to the encased Pi. And yes, he named his make Resin-in-resin – we salute you, sir!

resin.io in resin epoxy-encased Raspberry Pi

“Life uh…finds a way.”

Before he started the practical part of his project, he did his research to find a suitable resin. He found that epoxy types specifically designed for encasing electronics are very expensive. In the end, Ronald tried out a cheap type, usually employed to coat furniture, by encasing an LED. It worked perfectly, and he went ahead to use this resin for embedding the Pi.

Bubbleshooting epoxy

This was the first time Ronald had worked with resin, so he learned some essential things about casting. He advises other makers to mix the epoxy very, very slowly to minimize the formation of bubbles; to try their hands on some small-scale casting attempts first; and to make sure they’re using a large enough mold for casting. Another thing to keep in mind is that some components of the make will heat up and expand while the device is running.

His first version of an encased Pi was still connected to the outside world by its USB cable:

Ronald McCollam on Twitter

Updates don’t get more “hands off” than a Raspberry Pi encased in epoxy — @resin_io inside resin! Come ask me about it at @DockerCon!

Not satisfied with this, he went on to incorporate an inductive charging coil as a power source, so that the Pi could be totally insulated in epoxy. The Raspberry Pi Foundation’s Matt Richardson got a look the finished project at Maker Faire Bay Area:

MattRichardson🏳️‍🌈 on Twitter

If you’re at @makerfaire, you must check out what @resin_io is showing. A @Raspberry_Pi completely enclosed in resin. Completely wireless. https://t.co/djVjoLz3hI


The charging coil delivers enough power to keep the Pi running for several hours, but it doesn’t allow secure booting. After some head-scratching, Ronald came up with a cool solution to this problem: he added a battery and a magnetic reed switch. He explains:

[The] boot process is to use the magnetic switch to turn off the Pi, put it on the charger for a few minutes to allow the battery to charge up, then remove the magnet so the Pi boots.

Pi in resin controlled by resin.io

“God help us, we’re in the hands of engineers.”

He talks about his build on the resin.io blog, and has provided a detailed project log on Hackaday. For those of you who want to recreate this project at home, Ronald has even put together an Adafruit wishlist of the necessary components.

Does this resin-ate with you?

What’s especially great about Ronald’s posts is that they’re full of helpful tips about getting started with using epoxy resin in your digital making projects. So whether you’re keen to build your own wireless Pi, or just generally interested in embedding electronic components in resin, you’ll find his write-ups useful.

If you have experience in working with epoxy and electronic devices and want to share what you’ve learned, please do so in the comments!

Note: There’s been concern over encasing a battery in epoxy resin, so please do not try it at home – let’s leave that to Ronald.

The post Encased in amber: meet the epoxy-embedded Pi appeared first on Raspberry Pi.

Helix Display Brings Snake Into Three Dimensions

via hardware – Hackaday

Any time anyone finds a cool way to display in 3D — is there an uncool way? — we’re on board. Instructables user [Gelstronic]’s method involves an array of spinning props to play the game Snake in 3D.

The helix display consists of twelve props, precisely spaced and angled using 3D-printed parts, each with twelve individually addressable LEDs. Four control groups of 36 LEDs are controlled by the P8XBlade2 propeller microcontroller, and the resultant 17280 voxels per rotation are plenty to produce an identifiable image.

In order to power the LEDs, [Gelstronic] used wireless charging coils normally used for cell phones, transferring 10 W of power to the helix array.  A brushless motor keeps things spinning, while an Arduino controls speed and position via an encoder. All the links to the code used are found on the project page, but we have the video of the display in action is after the break.

There are some decidedly easier ways to achieve a volumetric display, as well as some that feel ripped straight from a video game.

[Thanks for the tip, Itay!]

Filed under: hardware, led hacks

Mitosis: Anatomy of a Custom Keyboard

via hardware – Hackaday

Ergonomic. Wireless. Low-latency. Minimalist. Efficient. How far do you go when you design your own open-source keyboard? Checking off these boxes and providing the means for others to do so, Redditor [reverse_bias] presents the Mitosis keyboard, and this thing is cool.

The custom, split– as the namesake implies — mechanical keyboard has 23 keys on each 10 cm x 10 cm half, and, naturally, a custom keymapping for optimal personal use.

Upper and lower PCBs host the keys and electronic circuits respectively, contributing to the sleek finished look. Key caps and mechanical switches were ripped from sacrificial boards: two Waveshare core51822 Bluetooth modules are used for communication, with a third module paired with a Pro Micro make up the receiver.[reverse_bias] spent a fair bit of time attempting to minimize the power consumption of the keyboard so it could be powered by a pair of coin batteries, giving it an estimated six month lifespan of daily use.  These are pinched between the upper and lower boards by little dabs of solder and the slight spring tension of the boards themselves. However, a bit of de-soldering is required to change the battery.

Laser-cut adhesive neoprene adorns the base, proving a comfortable springiness, grip, and protection for the pins as well as cushioning from any debris on the desk. The final product has almost zero flex, has a low enough profile to negate the need for a wrist rest. If you’re interested in building your own, [reverse_bias] has linked all the relevant files here.

Of course, one could always go the opposite way and opt for a more heavyweight option.

[Thanks for the tip, Tyberius Prime!]

Filed under: hardware

Pulsecounting and deepsleep based IoT water meter

via Dangerous Prototypes


Tisham Dhar has written an article detailing his pulsecounting and deepsleep based IoT water meter project:

I admit to being a tiny bit obsessed with monitoring utility bills and gathering data on my usage patterns blow-by-blow. The energy monitoring has reduced my electricity bills, so I wanted to have a go at the water usage. Granted a lot of the water bill is fixed supply costs and sewerage charges which I can’t do much about.
A while ago I made some pulse counting breakouts with the DS1682+ RTC. I have finally got a chance to put them to good use interfacing with my mechanical water meter. The water meter has a spinning permanent magnet and in principle this can trigger a reed switch and generate pulses for accumulation by the RTC.

More details at Tisham Dhar’s blog.

Duck DNS ESP8266 mini WiFi client

via Dangerous Prototypes


An ESP8266 Duck DNS client from Davide Gironi:

It is powered by USB, it can also be powered by the router USB port.
It’s built on a pretty old ESP-01 board.
It has two led, one is the ESP-01 WiFi connection status embedded one, the other is connected to the GPIO2 port, and it’s used for the DNS update status.

Project info at Davide Gironi’s blog.  Code is available on github.

Check out the video after the break.