Thinner with a simpler design but packing the same feature as before. At its heart is a raspberry pi zero W with a 3.5″ screen 480×320. It has all the GPIO pins available what aren’t being used by the screen. Its powered by a 2500mAh battery and has one full sized usb port. Its controlled by a bluetooth keyboard with trackpad
There are different ways to ruin a Linux system. For the Raspberry Pi which uses a micro SD card as the storage device by default, it comes with two challenges:
1.Excessive writes to the SD card can wear it out
2.Sudden power failure during a SD card write can corrupt the file system
For problem one I do I have a mitigation strategy (see “Log2Ram: Extending SD Card Lifetime for Raspberry Pi LoRaWAN Gateway“). Problem two can occur by user error (“you shall not turn it off without a sudo poweroff!”) or with the event of a power outage or black out. So for that problem I wanted to build a UPS for the Raspberry Pi.
First, I decided to upgrade from the Raspberry Pi Model B to a more recent Raspberry Pi Zero W that I had on hand. Wired Ethernet is so ~ 2013 after all, and wireless would be a lot more convenient. Next, I designed a 3D printed case for it, as my old laser-cut-acrylic-and-glue case also looked very dated. Finally, I replaced the software with a new program designed to poll the data from my octoprint server. In less than an afternoon, I had turned the old temperature/humidity display into something useful.
Eric Higgins has a nice build log on his Open Trickler project a bluetooth-enabled smart powder trickler from off-the-shelf parts for under $60:
Fundamentally, this is not a hard problem to solve. Read the value from the scale, run a motor that moves powder into the scale, turn off the motor when the scale reads the target weight. As with many projects, the devil’s in the details and there was plenty of trial-and-error during the development process to reach a working prototype.
In this project, a Raspberry Pi is used to read the weight from the scale and run a small vibration motor (like those in mobile phones) to trickle powder. An app on your phone or tablet connects to the Raspberry Pi over Bluetooth, and is used to set the target weight and start/stop the automatic trickling process.
I’ve been on a quest for while now trying to build a retropie handheld that was functional but didn’t break the bank. So far I’ve made ZeroBoy – A poor man’s retropie “portable” and a follow-up ZeroBoy rev C – An improved poor mans retropie portable. These were great but I think I have made a much better system with all the features included.
This article is about a small sensor node with a decorative case. It is based on the Raspberry Pi Zero W board with a custom sensor shield on top.
I publish all hardware files for a simple version of the sensor, so you should be able to build this kind of sensor nodes and use it to monitor anything you like. You can also extend/modify the design easily with additional sensors. Nevertheless, the case lid design is based around the Plantower PMSA003 particle sensor. It has all required air vents for this use.
For years I’ve followed the “uRadMonitor”, a device that does air quality monitoring and radiation monitoring. I’ve played with geiger counter projects before and frankly found them to be not very interesting. However, the idea of monitoring air quality is something that seemed like it might yield interesting data. For example, as I’ve started to become involved in 3D printing, it would be useful to see whether or not 3D printing affected the air quality. It would also be useful to correlate my results with what my region reports for outdoor air quality.
The implementation is simple genius. It’s a browser that starts up full screen (kiosk mode) and just sits there and updates occasionally. DakBoard provides the private webpage and tools to make that happen. You can certainly build this yourself with any number of open source tools. I chose DakBoard because it was simple, beautiful, and I was able to get the whole thing done in less than an hour. I’m sure I’ll spend many hours tweaking it through. There’s also the very popular MagicMIrror platform, so lots of choice and power in this space!
Above you can see my prototype. I’m using a 4.2″ e-Paper display from Gooddisplay, together with the Waveshare breakout board. I have a couple of ENS1J-B28-R00128 optical encoders that I attained on eBay. I specifically chose these encoders instead of traditional electro-mechnical encoders due to the high numbers of pulses per revolution. A typical electro-mechanical encoder will net about 24 pulses per revolution. The optical encoders I bought on ebay are 128 pulses per revolution. Our 4.2″ ePaper has 400×300 pixels. To traverse the major axis would require 16 full turns of the electromechical encoder but only 3 turns of the optical encoder.
The hardware is so simple that there’s not much more to say. The encoders are connected to GPIO pins of a Raspberry Pi. Note that there are resistors inline on the encoder outputs as the encoders are 5V and the Raspberry Pi uses 3.3V GPIO. The e-ink display is connected to the SPI bus.
See the full post on his blog here and the GitHub repository here.
A few days ago I started playing with some idea I had from a few weeks already, using a Raspberry Pi Zero W to make a mini WiFi deauthenticator: something in my pocket that periodically jumps on all the channels in the WiFi spectrum, collects information about the nearby access points and their connected clients and then sends a deauthentication packet to each one of them, resulting in some sort of WiFi jammer on the 802.11 level. As an interesting “side effect” of this jammer (the initial intent was purely for the lulz) is that the more it deauths, the higher the changes to also sniff WPA2 handshakes.