Cute Brass Lunar Lander Is A Neat Little Environment Monitor

January 19, 2024 by Lewin Day 8 Comments

Sometimes form can make a project more attractive than its simple function. [Mohit Bhoite]’s free-form builds are great examples of this. His latest effort is a gorgeous little device that displays environmental readings, and it’s shaped like a lunar lander. (Nitter) Just exquisite!

The device is based around a Seeedstudio XIAO nRF52840 dev board. It’s hooked up to a BME280 sensor which delivers temperature, humidity and air pressure readings from the immediate environment. These readings are displayed on a tiny 128×32 OLED display, along with the current time. Power is via a compact 14250 lithium cell.

So far, so simple, but the real magic is in the housing. It’s a wireframe lunar lander lookalike which [Mohit] put together using brass wire and some careful soldering. It adds so much to the build, which wouldn’t be nearly as attractive if just assembled on a PCB. It’s not his first rodeo, either. He previously built a cute device (Nitter) with an animated face in 2019 using similar techniques; it used a CCS811 gas sensor to detect air quality.

Often, we find ourselves falling most in love with devices that please the eye. [Mohit] certainly demonstrates a great skill in building things that fit this brief. Sometimes, it only takes a bit of thought and careful application of the mind to bring a beautiful aesthetic to your projects, and the results can be most rewarding. Try his Hackaday Supercon talk if you want to learn more. Continue reading “Cute Brass Lunar Lander Is A Neat Little Environment Monitor” →

Pocket CO2 Sensor Doubles As SMD Proving Ground

October 10, 2023 by Tom Nardi 4 Comments

While for some of us it’s a distant memory, every serious electronics hobbyist must at some point make the leap from working with through-hole components to Surface Mount Devices (SMD). At first glance, the diminutive components can be quite intimidating — how can you possibly work with parts that are literally smaller than a grain of rice? But of course, like anything else, with practice comes proficiency.

It’s at this silicon precipice that [Larry Bank] recently found himself. While better known on these pages for his software exploits, he recently decided to add SMD electronics to his repertoire by designing and assembling a pocket-sized CO2 monitor. While the monitor itself is a neat gadget that would be worthy of these pages on its own, what’s really compelling about this write-up is how it documents the journey from SMD skeptic to convert in a very personal way.

A fine-tipped applicator will get the solder paste where it needs to go.

At first, [Larry] admits to being put off by projects using SMD parts, assuming (not unreasonably) that it would require a significant investment in time and money. But eventually he realized that he could start small and work his way up; for less than $100 USD he was able to pick up both a hot air rework station and a hotplate, which is more than enough to get started with a wide range of SMD components. He experimented with using solder stencils, but even there, ultimately found them to be an unnecessary expense for many projects.

While the bulk of the page details the process of assembling the board, [Larry] does provide some technical details on the device itself. It’s powered by the incredibly cheap CH32V003 microcontroller — they cost him less than twenty cents each for fifty of the things — paired with the ubiquitous 128×64 SSD1306 OLED, TP4057 charge controller, and a SCD40 CO2 sensor.

Whether you want to build your own portable CO2 sensor (which judging from the video below, is quite nice), or you’re just looking for some tips on how to leave those through-hole parts in the past, [Larry] has you covered. We’re particularly eager to see more of his work with the CH32V003, which is quickly becoming a must-have in the modern hardware hacker’s arsenal.

Continue reading “Pocket CO2 Sensor Doubles As SMD Proving Ground” →

e-paper display showing hand-drawn fonts attached to a custom controller PCB

Recycling Junk E-tags Into A LoRaWAN AQI Sensor

September 28, 2022 by Dave Rowntree 6 Comments

E-paper interfacing circuit is just a simple switched-mode power supply — Interfacing to E-paper displays is nothing to be scared of

[Aduecho] had seen those cheap eBay deals of e-paper-based pricing tags, and was wondering if they could be hacked to perform some other tasks. After splitting the case open, the controller chip was discovered to be a SEM9110, with some NFC hardware support but little else. [aduecho] was hoping to build some IoT-connected air quality indicator (AQI) units but the lack of a datasheet for SEM9110 plus no sensors in place meant the only real course of action was to junk the PCB and just keep the E-paper display and the batteries. These units appeared to be ‘new old’ stock, so there was a good chance that both would be fresh and ripe for picking.

The PCB [aduecho] came up with is mechanically the same as the original unit, but now sports a Seeed studio Wio-E5 LoRa module, which uses the STM32WLE5 from ST for the heavy lifting. This has what looks like a Semtech SX126x integrated on-die (we can’t think of a sane way an actual SX126x die could be flip-chip mounted, but you never know). Using this module is a snap, needing only very minimal antenna-matching components and a spot of decoupling to function. On the sensing side of things, a Bosch BME680 gas sensor handling the AQI measurements, and a Bosch BMI270 6-axis IMU, provides a gyro and accelerometer, for all those planned user interaction features. As can be seen from the schematic, interfacing the EPD is pretty straightforward, just a handful of parts are needed to generate the necessary bipolar gate voltages via a simple SMPS circuit. The display controller handles it all internally, programmed via an SPI interface.

One area we’re quite fond of in this project are the neat hand-drawn icons, and variable width font, giving the display a kind of note-like quality when drawn on the low-ish contrast e-paper display.

Air quality measurement projects grace these pages from time to time, like this hacked Ikea Vindriktning, and this very similar Wio-E5-based project we covered last month.

LoRa Air Quality Monitor Raises The Bar On DIY IoT

August 30, 2022 by Tom Nardi 15 Comments

We’ve seen an incredible number of homebrew environmental monitors here at Hackaday, and on the whole, they tend to follow a pretty predicable pattern. An ESP8266 gets paired with a common temperature and humidity sensor, perhaps a custom PCB gets invited to the party, and the end result are some values getting pushed out via MQTT. It’s a great weekend project to get your feet wet, but not exactly groundbreaking in 2022.

Which is why we find the AERQ project from [Mircea-Iuliu Micle] so refreshing. Not only does this gadget pick up temperature and humidity as you’d expect, but its Bosch BME688 sensor can also sniff out volatile organic compounds (VOCs) and gases such as carbon monoxide and hydrogen. The datasheet actually claims this is the “first gas sensor with Artificial Intelligence (AI)”, and while we’re not sure what exactly that means in this context, it’s a claim that apparently warrants a price tag of $15+ USD a pop in single quantities.

There’s an AI hiding in there someplace.

But the fancy sensor isn’t the only thing that sets AERQ apart from the competition. Instead of a member of the ubiquitous ESP family, it’s using the Wio-E5, a relatively exotic STM32 package that integrates a long-range LoRa radio. [Mircea-Iuliu] has paired that with a Linx USP-410 chip antenna or, depending on which version of the four-layer PCB you want to use, a u.Fl connector for an external antenna. The whole thing is powered by a simple USB connection, and its Mbed OS firmware is setup to dump all of its collected data onto The Things Network.

All told, it’s a very professional build that certainly wouldn’t look out of place if it was nestled into some off-the-shelf air quality monitor. While the high-end detection capabilities might be a bit overkill for home use, [Mircea-Iuliu Micle] points out that AERQ might provide useful insight for those running indoor events as COVID-19 transitions into its endemic stage.

A Merciless Environmental Monitoring System

August 10, 2022 by Tom Nardi 12 Comments

We’ve seen plenty of environmental monitoring setups here on Hackaday — wireless sensors dotted around the house, all uploading their temperature and humidity data to a central server hidden away in some closet. The system put together by [Andy] from Workshopshed is much the same, except this time the server has been designed to be as bright and bold as possible.

The use of Mosquitto, InfluxDB, Node Red, and Grafana (M.I.N.G) made [Andy] think of Ming the Merciless from Flash Gordon, which in turn inspired the enclosure that holds the Raspberry Pi, hard drive, and power supply. Some 3D printed details help sell the look, and painted metal mesh panels make sure there’s plenty of airflow.

While the server is certainly eye-catching, the sensors themselves are also worth a close look. You might expect the sensors to be based on some member of the ESP family, but in this case, [Andy] has opted to go with the Raspberry Pi Pico. As this project pre-dates the release of the wireless variant of the board, he had to add on an ESP-01 for communications as well as the DTH11 temperature and humidity sensor.

For power each sensor includes a 1200 mAh pouch cell and a Pimoroni LiPo SHIM, though he does note working with the Pico’s energy saving modes posed something of a challenge. A perfboard holds all the components together, and the whole thing fits into an understated 3D printed enclosure.

Should you go the ESP8266/ESP32 route for your wireless sensors, we’ve seen some pretty tidy packages that are worth checking out. Or if you’d rather use something off-the-shelf, we’re big fans of the custom firmware developed for Xiaomi Bluetooth thermometers.

Continue reading “A Merciless Environmental Monitoring System” →

Jigglypuff Sensor Breathes CO2 So You Don’t Have To

November 16, 2021 by Tom Nardi 3 Comments

We’ve seen a lot of environmental monitoring projects here at Hackaday. Seriously, a lot. They usually take the form of a microcontroller, a couple sensors, and maybe a 3D printed case to keep it all protected. They’re pretty similar functionally as well, with the only variation usually coming in the protocol used to communicate their bits of collected data.

But even when compared with such an extensive body of previous work, this Jigglypuff IoT environmental monitor created by [Kutluhan Aktar] is pretty unusual. Sure, the highlights are familiar. Its MH-Z14A NDIR CO2 sensor and GP2Y1010AU0F optical dust detector are read by a WiFi-enabled microcontroller, this time the Arduino Nano RP2040 Connect, which ultimately reports its findings to the user via Telegram bot. There’s even a common SSD1306 OLED display on the unit to show the data locally. All things we’ve seen in some form or another in the past.

Testing the electronics on a bread board.

So what’s different? Well, it’s all been mounted to a huge Pokémon PCB, obviously. Even if you aren’t a fan of the pocket monsters, you’ve got to appreciate that bright pink solder mask. Honestly, the whole presentation is a great example of the sort of PCB artwork we rarely see outside of the BadgeLife scene.

Admittedly, there’s a lot easier ways to get notified about the air quality inside your house. We’re also not saying that haphazardly mounting your electronics onto a PCB designed to look like a character from a nearly 20+ year old Game Boy game is necessarily a great idea from a reliability standpoint. But if you were going to do something like that, then this project is certainly the one to beat.

NRF52 Weather Station Gives Forecast With Style

March 11, 2021 by Tom Nardi 9 Comments

We’re no strangers to DIY environmental monitors around these parts, in fact, it seems like that’s one of the most common projects hackers take on when confronted with the power of a modern Internet-connected microcontroller. But among such projects, this miniature nRF52-based weather station built by [Andrew Lamchenko] is among the most polished we’ve seen.

Externally, this looks as though it could easily be a commercial product. The graphical interface on the ePaper display is very well designed, delivering plenty of data while still looking attractive enough to hang in the kitchen. The enclosure is 3D printed, but [Andrew] poured enough elbow grease into sanding and polishing the front that you might not realize it at first glance.

Internally it uses the popular BME280 sensor to detect temperature, humidity, and barometric pressure, though the custom PCB is also compatible with the similar SI7021 and HTU21D sensors if you want to switch things up.

That said, you really want the ability to measure pressure, as it allows the firmware to do its own basic weather forecasting. All the collected data is beamed out over Bluetooth Low Energy (BLE), where it can be collected by the open source MySensors IoT framework, but we imagine it wouldn’t take much work to integrate it into your home automation system of choice.

As excited as we might be about the prospect of repurposing things such as electronic shelf labels, we’re happy to see the prices for general purpose electronic paper screens finally dropping to the point where projects of this caliber are within the means of the hacker crowd.

Continue reading “NRF52 Weather Station Gives Forecast With Style” →