AAA Powered LoRa Mailbox Sensor Goes The Distance

As more of the world’s communication moves into the electronic realm, a casualty has come in the physical mail. Where once each new day might have brought with it a bulging mailbox, today it’s not uncommon for days to pass with not even so much as a bill or a coupon book. For [Eivholt] this presents a problem: he doesn’t want to miss a parcel but most visits to the mailbox are futile. His solution is a LoRa-connected mailbox monitor that sips power from a pair of AAA batteries to the extent that so far it’s run for over two years on a single set.

At its heart is a single board, a Talk2 Whisper Node. This packs a low-power version of the ATmega328 microcontroller alongside a LoRa radio and an efficient power regulator allowing it to draw only 8.70 uA in standby mode, waking up only for extremely short periods to check for mail and report via LoRa to The Things Network. The sensor is simply a microswitch, selected after finding a reed switch problematic to install. Finally an SDR was used to debug the operation of the radio.

The write-up also provides an introduction to extreme low power projects, including some tips on measuring such tiny currents. Even if you have no interest in a mailbox, any tricks that can help maximize power efficiency are always worth taking a look at. Check out the video after the break to see this radio-equipped mailbox in action.

Continue reading “AAA Powered LoRa Mailbox Sensor Goes The Distance”

A Battery Sipping Cellular Mailbox Notifier

Like many of us, [Zak Kemble] has an indeterminate number of tiny packages coming his way from all over the globe at any given time. Unfortunately, the somewhat unpredictable nature of the postal service where he lives meant he found himself making a lot of wasted trips out to the mailbox to see if any overseas treasures had arrived for him. To solve the problem, he decided to build an Internet-connected mailbox notification system that could work within some fairly specific parameters.

For one thing, the mailbox is too distant to connect directly to it over WiFi. [Zak] mentions that 433 MHz might have been an option, but he decided to skip that entirely and just connect it to the cellular network with an A9G GPRS/GSM module from A.I. Thinker. This device actually has its own SDK that allows you to create a custom firmware for it, but unfortunately the high energy consumption of the radio meant it would chew through batteries too quickly unless it had a little extra help.

Not wanting to have to change the batteries every couple months, [Zak] added a ATtiny402 to handle the notifier’s power management needs. By using a P-MOSFET to completely cut power to the A9G, the notifier can save an incredible amount of energy by only activating the cellular connection once it actually needs to send a notification; which in this case takes the form of an HTTP request that eventually works its way to a Telegram group chat.

To cut a long story short, testing seems to indicate that the notifier can fire off approximately 800 requests before needing its 10440 lithium battery recharged. Given how often [Zak] usually receives mail, he says that should last him around five years.

The A9G module, the ATtiny402, a BME280 environmental sensor (because, why not?), the battery, and all the ancillary support hardware are on a very professional looking PCB. That goes into a relatively rugged enclosure that’s designed to keep the electronics from shorting out on the mailbox’s metal case as well as keeping any particularly weighty parcels from crushing it.

If you’ve got the freedom so mount whatever you want outside, then you can certainly build a more technically impressive mailbox. But considering the limitations [Zak] had to work around, we think he did an excellent job.

Hardware Notifications For ISS Flybys

Since Sputnik launched in the 1950s, its been possible to look outside at night and spot artificial satellites orbiting with the naked eye. While Sputnik isn’t up there anymore, a larger, more modern satellite is readily located: the International Space Station. In fact, NASA has a program which will alert anyone who signs up when the ISS is about to fly overhead. A better alert, though, is this ISS notifier which is a dedicated piece of hardware that guarantees you won’t miss the next flyby.

This notifier is built around the Tokymaker, a platform aimed at making electronics projects almost painfully easy to learn. Connections to various modules can be made without soldering, and programming is done via a graphical interface reminiscent of Scratch. Using these tools, [jaime_lc98] designed a tool which flips up a tiny paper astronaut whenever the ISS is nearby. The software side takes advantage of IFTTT to easily and reliably control the servo on the Tokymaker.

The project pages goes into detail about how to set up IFTTT and also how to use the block-style language to program the Tokymaker. It’s pretty straightforward to get it up and running, relatively inexpensive, and looks like a great way to get the miniature hackers in your life excited about space. If they happen to learn a little something in the proces, well, we won’t tell them if you won’t. It might also be a good stepping stone on the way to other ISS-related hacks.

Code Review Lamp Subtly Reminds You To Help Your Fellow Developer

[Dimitris Platis] works in an environment with a peer review process for accepting code changes. Code reviews generally are a good thing. One downside though, is that a lack of responsiveness from other developers can result in a big hit to team’s development speed. It isn’t that other developers are unwilling to do the reviews, it’s more that individuals are often absorbed in their own work and notification emails are easily missed. There is also a bit of a “tragedy of the commons” vibe to the situation, where it’s easy to feel that someone else will surely attend to the situation, but often no one does. To combat this, [Dimitris] built this Code Review Lamp, a subtle notification that aims to prod reviewers into action.

The lamp is based on a ring of RGB LEDs and a Wemos D1 Mini board. The Wemos utilizes the popular ESP8266, so it’s easy to develop for. The LED ring and Wemos are tied together with a slick custom PCB. Mounting the LED ring on the top of the PCB and the Wemos on the bottom allows for easy powering via a USB cable while directing light upward.  The assembly is placed in a translucent 3D printed enclosure creating a pleasant diffuse light source.

Every developer gets a Code Review Lamp. The lamps automatically log in to the change management system to check whether anything is awaiting review. If a review is ready, the Lamp glows in a color specific to the individual developer. All this serves as a gentle but persistent reminder that someone’s work is being held up until a review is completed.

We love the way that the device has a clear purpose: it does its job without any unnecessary features or parts. It’s similar to this ESP8266 IoT Motion Sensor in that it has a single job to do, and focuses on it well.

Continue reading “Code Review Lamp Subtly Reminds You To Help Your Fellow Developer”

Popup Notification Dinosaur

There’s a lot going on our virtual spaces, and anyone with a smart phone can attest to this fact. There are pop-up notifications for everything you can imagine, and sometimes it’s possible for the one really important notification to get lost in a sea of minutiae. To really make sure you don’t miss that one important notification, you can offload that task to your own personal dinosaur.

The 3D-printed dinosaur has a rack-and-pinion gear set that allows it to extend upwards when commanded. It also has a set of LEDs for eyes that turn on when it pops up. The two servos and LEDs are controlled by a small Arduino in the base of the dinosaur. This Arduino can be programmed to activate the dinosaur whenver you like, for an email from a specific person, a reply to a comment on Reddit, or an incoming phone call to name a few examples. Be sure to check out the video below the break.

With this dinosaur on your desk, it’s not likely you’ll miss its activation. If you’d like something that has the same function but with less movement and more lights, there’s also a notification 3D cube made out of LEDs that’s sure to catch your eye as well. Continue reading “Popup Notification Dinosaur”

LED Notification Cube Is A Good First Project

Two years ago, [Matt] made a move away from his software hacks and into the physical world. He was part of a pilot program to provide mentorship to children as part of the Maker Education Initiative. This program gave him access to 3D printers, CNC machines, and laser cutters within the New York Hall of Science makerspace. [Matt] chose to build an illuminated notification cube for his first physical project. The idea being that smart phones have so many alerts, many of which are unimportant. His project would help him to visualize and categorize each alert to better understand its importance.

The brain of the system is a Raspberry Pi. [Matt] found a Python library that allowed him to directly control an RGB LED strip based on the LPD8806 chip. He wired the data pins directly to the Pi and used an old 5V cell phone charger to power the LEDs. The strip was cut into smaller strands. Each face of the cube would end up with three strands of two LEDs each, or six LEDs per side. [Matt] found a mount for the Pi on Thingiverse and used a 3D printer to bring it into existence. The sides were made of frosted laser cut acrylic. The frosted look helps to diffuse the light from the LEDs.

Over time [Matt] found that the cube wasn’t as useful as he originally thought it would be. He just didn’t have enough alerts to justify the need. He ended up reprogramming the Pi to pull weather information instead, making use of the exact same hardware for another, more useful purpose.

Great Scott! A Flux Capacitor Notification Light

If you are into your social media, then you probably like to stay updated with your notifications. [Gamaral] feels this way but he wasn’t happy with the standard way of checking the website or waiting for his phone to alert him. He wanted something a little more flashy. Something like a flux capacitor notification light. This device won’t send his messages back in time, but it does look cool.

He started with an off-the-shelf flux capacitor USB charger. Normally this device just looks cool when charging your USB devices. [Gamaral] wanted to give himself more control of it. He started by opening up the case and replacing a single surface mount resistor. The replacement component is actually a 3.3V regulator that happens to be a similar form factor as the original resistor. This regulator can now provide steady power to the device itself, as well as a ESP8266 module.

The ESP8266 module has built-in WiFi capabilities for a low price. The board itself is also quite small, making it suitable for this project. [Gamaral] used just two GPIO pins. The first one toggles the flux circuit on and off, and the second keeps track of the current state of the circuit. To actually trigger the change, [gamaral] just connects to the module via TCP and issues a “TIME CIRCUIT ON/OFF” command. The simplicity makes the unit more versatile because an application running on a PC can actually track various social media and flash the unit accordingly.