Duck And Cover With This WiFi “Geiger Counter”

April 8, 2019 by Tom Nardi 10 Comments

There’s perhaps no sound more recognizable than the frantic clicking of a Geiger counter. Not because this is some post-apocalyptic world in which everyone is personally acquainted with the operation of said devices, but because it’s such a common effect used in many movies, TV shows, and video games. If somebody hears that noise, even if it doesn’t really make sense in context, they know things are about to get serious.

Capitalizing on this phenomena, [Anton Haidai] has put together a quick hack which turns the ESP8266 into a “Geiger counter” for WiFi. Rather than detecting radiation, the gadget picks up on the strongest nearby WiFi signal and will start clicking in response to signal strength. As the signal gets stronger, so does the clicking. While primarily a novelty, it’s an interesting idea that could potentially be useful for things like fox hunting.

The hardware is really about as simple as it gets, just a basic buzzer attached to one of the digital pins on a NodeMCU development board. This project is more of a proof of concept, but if it were to be developed further it would be interesting to see the electronics placed into a 3D printed replica of one of the old Civil Defense Geiger counters. Perhaps even integrating an analog gauge that can bounce around in response to signal strength.

Software-wise there is the option of locking onto one single network SSID or allowing the device to find the strongest network in the area. Even if you’re not in the market for a chirping WiFi detector, the code is a good example of how you can detect signal RSSI and act on it accordingly; a neat trick which might come in handy in a future project.

If you’re more interested in the real thing, we’ve got plenty of DIY Geiger counters in the archive for you to check out. From diminutive builds that can be mounted to the top of a 9V battery to high-tech solid state versions with touch screen interfaces, you should have plenty of inspiration if you’re looking to kit yourself out before your next drive through the Chernobyl Exclusion Zone.

Continue reading “Duck And Cover With This WiFi “Geiger Counter”” →

A Contact Lens Launcher That Knows The Weather

April 7, 2019 by Tom Nardi 10 Comments

They say that necessity is the “Mother of Invention”, but over the years we’ve started to suspect that her cousin might be an underutilized microcontroller. How else can you explain projects like the latest from [MNMakerMan], which takes the relatively simple concept of a contact lens holder and manages to turn it into an Internet-connected electronic appliance? Not that we’re complaining, of course.

He started out with a simple 3D printed holder for his wall that would let him pull out his daily lenses, which worked well enough and gained some popularity on Thingiverse. But he wondered if there wasn’t some way he could use a servo to automate the process. While he was at it, he might as well play with some of the components he’s been meaning to get some hands-on experience with, such as those little OLED displays all the cool kids are using.

Modifying his original design to incorporate servos in the bottom, he added a central compartment that would house an ESP8266 and a simple proximity sensor made from an IR LED and photodiode. The sensor tends to be a little twitchy, so he left a potentiometer inside the device so he can fine tune it as needed.

Strictly speaking the OLED display isn’t actually required for this project, but since he had a WiFi capable microcontroller sitting there doing basically nothing all day anyway, he added in a feature that shows the weather forecast. It’s not much of a stretch to say that the first thing you’d want to see in the morning after regaining the sense of sight is a readout of what the day’s weather will be, so we think it’s a fairly logical extension of the core functionality. Bonus points if he eventually adds in a notification to remind him it’s time to order more lenses when the dispenser starts getting low.

If you don’t have any contact lenses you need dispensed, never fear. A similar concept can be used to fire off your customized swag at hacker events. Don’t have any of that either? Well in that case you can always build a candy dispenser for Halloween.

Continue reading “A Contact Lens Launcher That Knows The Weather” →

Hacker Abroad: Visiting Espressif And Surprising Subway Ads

March 22, 2019 by Mike Szczys 17 Comments

Thursday was my final day in Shanghai. After spending all of Wednesday at Electronica Asia, I headed over to the Espressif Headquarters which is just one subway stop away. This is of course the company behind the well-known ESP8266 and its younger sibling, the ESP32. My host was Ivan Grotkothov, Director of Software Platforms. The backstory on how he found his way to the company is truly interesting, as are the stories he shared on some of the legend and lore surrounding the WiFi capable chips the company makes — and the new one whose existence just leaked out this week.

Join me below for that and few other fun things from my last day in this city of 26 million people.

Continue reading “Hacker Abroad: Visiting Espressif And Surprising Subway Ads” →

Old Wireless Switches Join The Internet Of Things

March 21, 2019 by Zoe Skyforest 14 Comments

Just about any appliance comes in an internet enabled version nowadays. However, even the oldest gear can be switched on and off with an Internet connected power socket. [Bill] is in the process of automating his home, and found some old radio controlled power sockets that badly needed to join the 21st Century. Hacking ensued.

The first set of switches [Bill] came across were easy to work with. Eager to keep things as functional as possible, ESP8266s with Tasmota firmware were wedged into the enclosures. With a bit of circuit sleuthing, [Bill] was able to set up the switches to respond to commands from both the ESP8266 as well as the original push buttons and radio remote.

[Bill] later came across some black switches, which were not up to his standards. These switches were gutted entirely, being used only for their mains plug and enclosure. The relays inside were replaced with 5V versions which were easier to trigger from the ESP8266’s outputs.

[Bill[ readily admits that the cost benefits over buying off-the-shelf Sonoff modules don’t really add up, but good hackers rarely let such concerns get in the way of a fun project. Around these parts, we see plenty of hacks to automate your house – like this zero-intrusion light switch mod. Happy hacking!

Library Makes ESP Over The Air Updates Easy

March 21, 2019 by Al Williams 19 Comments

Potentially, one of the great things about having a device connected to the network is that you can update it remotely. However, how do you make that happen? If you use the Arduino setup for the ESP8266 or ESP32, you might try [scottchiefbaker’s] library which promises to make the process easy.

Adding it looks to be simple. You’ll need an include, of course. If you don’t mind using port 8080 and the path /webota, you only need to call handle_webota() from your main loop. If you want to change the defaults, you’ll need to add an extra call in your setup. You also need to set up a few global variables to specify your network parameters.

Continue reading “Library Makes ESP Over The Air Updates Easy” →

An ESP8266 Sundial For Your Wall

March 20, 2019 by Tom Nardi 9 Comments

Hackers absolutely love building clocks. Seriously, there are few other devices for which we’ve seen such an incredible number of variations. But while the clocks that hackers build might blink out the time in binary, or write it out in words, they generally don’t feature hands. Apparently in 2019 it’s more reasonable to read binary than know which way the “little hand” is supposed to be pointing.

This ESP8266 powered “shadow clock” from [Dheera Venkatraman] technically keeps that tradition intact, but only just. His clock doesn’t feature physical hands, but it does use a strip of RGB LEDs to cast multi-colored shadows which serve the same function. With his clock, you don’t even have to try and figure out which hand is the big one, since they’re all the same length. Now that’s what we call progress.

Probably the biggest surprise about this clock, beyond how legitimately good it looks hanging on the wall, is how little work it takes to build your own version. That’s because [Dheera] specifically set out to design something that was cheaper and easier to build than what he’d seen previously, and we think he delivered on that goal in a big way. All you need are the 3D printed components, an ESP8266 board, and a strip of 144 WS2812B LEDs.

The software side of the project is similarly simplistic, and all you need to do is plug in your WiFi network credentials to have the ESP pull the current time from NTP. If you were so inclined, his source code would be an excellent base on which to implement additional features such as animations at the top of the hour.

Compared to something like the Bulbdial clock from 2009, it’s incredible how simple some of these projects have become in the last decade. With the tools and components available to hackers and makers today, there’s truly never been a better time to build something amazing.

ESP8266 Gets Its Game On With Open Source Engine

March 11, 2019 by Tom Nardi 12 Comments

This is likely not to come as much of a shock to you, but the ESP8266 is pretty popular. At this point, we’re more surprised when a project that hits the tip line doesn’t utilize this incredibly cheap WiFi-enabled microcontroller. If you’re making a gadget that needs to connect to the Internet, there’s a good chance some member of the ESP family is going to be a good choice. But is it a one-trick MCU?

Well, judging by software frameworks like the “Little Game Engine” created by [Igor], it looks like the ESP is expanding its reach into offline projects as well. While it might not turn the ESP8266 into a next-gen gaming powerhouse, we’ve got to admit that the demos shown off so far are pretty impressive. When paired with a couple of buttons and a TFT display such as the ILI9341, the ESP could make for a particularly pocket-friendly game system.

The game engine that [Igor] has developed provides the programmer with a virtual screen resolution of 128×128, a background layer, and 32 sprites which offer built-in tricks like collision detection and rotation. All while running at a respectable 20 frames per second. This environment is ideal for the sort of 2D scrolling games that dominated the 8 and 16-bit era of gaming, and as seen in the video after the break, it can even pull off a fairly decent clone of “Flappy Bird”.

In addition, [Igor] created an online emulator and compiler which allows you to develop games using his engine right in your web browser. You can load up a selection of example programs and execute them to see what the engine is capable of, then try your hand at developing your own game before ever having to put the hardware together. Incidentally, the performance of this online development environment is fantastic; with even the fairly complex “Flappy Bird” example code compiling and starting in the emulator nearly instantaneously.

This isn’t the first handheld game we’ve seen powered by the ESP8266, but it would be fair to say this one is a generational leap over its predecessors. Of course, if you really want to start throwing around some pixels, you might want to make the leap to the ESP32; which is the heart of the incredibly awesome (and tiny) PocketSprite.

Continue reading “ESP8266 Gets Its Game On With Open Source Engine” →