For many people, phone and Internet connectivity are omnipresent and always available. It’s possible to upload selfies from a Chinese subway, and search for restaurant reviews in most highway towns, all thanks to modern cellular connectivity. However, in emergencies, we’re not always so lucky. If towers fail or user demand grows too large, things can collapse all too quickly. It’s in these situations that HELPER aims to flourish.
HELPER stands for Heterogeneous Efficient Low Power Radio. It’s a radio system designed to operate in the absence of any infrastructure, creating a pop-up network to serve community needs in disaster areas. Users can share information about available resources, like water, gasoline and food, while emergency workers can coordinate their response and direct aid to those who need it.
It’s a system built around commonly available parts. Raspberry Pis run the back end software and communicate with individuals over WiFi, with LoRa radios handling the longer-range communication from node to node. Combining this communication ability with GPS location and stored map data allows users to more easily find resources and assistance when things go wrong. The journal article is freely available for those wishing to learn more about the project.
It’s a project which aims to keep people safe when conventional networks go down. The key is to remember that once disaster strikes, it’s usually too late to start distributing radio hardware – emergency gear should be in place well before things start to go south. Of course, there’s also the government side of the equation – in the USA, the Emergency Broadcast System is a great example of emergency communications done right. Video after the break.
Those who love a detailed build log will enjoy this. The pager features everything up to and including the kitchen sink. A Cortex M0+ runs the show, flashed with an Arduino compatible bootloader, while a RFM95W module handles the LoRa communications. There’s a pager vibrator and piezo buzzer for notifications, along with a LiPo charger to make keeping the battery topped up easy. There’s even an RTC and soft-power button module.
Even if the LoRa side of things isn’t relevant to your interests, it’s a great example of how to build a useful tool rather than just a proof-of-concept. Things like an easy-to-use interface and simple battery charging go a long way to making something usable in the field. [5Volt-Junkie] even goes so far as to point out that even solder mask matters – if you’re using an infrared oven, your black boards will need a different profile to the usual green PCBs.
All the hard work has paid off, creating an attractive end product that we’d be proud to pack with the rest of our ham gear. LoRa is a useful platform, and as we’ve seen, it can be useful for everything from viticulture to meterology. Video after the break.
Making wine isn’t just about following a recipe, it’s a chemical process that needs to be monitored and managed for best results. The larger the batch, the more painful it is to have something go wrong. This means that the stakes are high for small vineyards such as the family one [Mare] works with, which have insufficient resources to afford high-end equipment yet have the same needs as larger winemakers. The most useful thing to monitor is the temperature profile of the fermentation process, and [Mare] created an exceptional IoT system to do that using LoRa wireless and solar power.
It’s not enough just to measure temperature of the fermenting liquid; viewing how the temperature changes over time is critical to understanding the process and spotting any trouble. [Mare] originally used a Raspberry Pi, I2C temperature sensor, and a Wi-Fi connection to a database to do the monitoring. This was a success, but it was also overkill. To improve the system, the Raspberry Pi was replaced with a LoRaDunchy board, an STM-based module of [Mare]’s own design which is pin-compatible with the Arduino Nano. It includes a battery charger, power management, and LoRa wireless communication. Adding a solar cell and lithium-polymer battery was all it took to figuratively cut the power cord.
Sensing the temperature of fermentation is done by sealing the temperature sensor into a thin aluminum tube, and lowering that into the vat. There it remains, with the LoRaDunchy board periodically waking up to read the sensor and report the tempurature over LoRa before going back to sleep, all the while sipping power from the battery which in turn gets recharged with solar power.
It’s an elegant system that has already paid off. A 500 litre vat of wine generated an alarm when the temperature rose above 24 Celsius for 10 minutes. An email alert allowed the owner to begin mixing the solution and add ice water to put the brakes on the runaway reaction. The temperature dropped and slow fermentation resumed, thanks to the twin powers of gathering the right data, then doing something meaningful with it.
[Mare] has a visual guide and simple instructions for making DIY mini helical 868 MHz antennas for LoRa applications. 868 MHz is a license-free band in Europe, and this method yields a perfectly serviceable antenna that’s useful where space is constrained.
The process is simple and well-documented, but as usual with antenna design it requires attention to detail. Wire for the antenna is silver-plated copper, salvaged from the core of RG214U coaxial cable. After straightening, the wire is wound tightly around a 5 mm core. 7 turns are each carefully spaced 2 mm apart. After that, it’s just a matter of measuring and bending the end for soldering to the wireless device in question. [Mare] has used this method for wireless LoRa sensors in space-constrained designs, and it also has the benefit of lowering part costs since it can be made and tested in-house.
Antennas have of course been made from far stranger things than salvaged wire; one of our favorites is this Yagi antenna made from segments of measuring tape.
Our five rounds of Hackaday Prize 2018 challenges have just wrapped up, and we’re looking forward to see where the chips fall in the final ranking. While we’re waiting for the winners to be announced at Hackaday Superconference, it’s fun to take a look back at one of our past winners. Watch [Reinier van der Lee] give the latest updates on his Vinduino project (video also embedded after the break) to a Hackaday Los Angeles meetup earlier this year.
Vinduino started with [Reinier]’s desire to better understand what happens to irrigation water under the surface, measuring soil moisture at different depths. This knowledge informs more efficient use of irrigation water, as we’ve previously covered in more detail. What [Reinier] has been focused on is improving usability of the system by networking the sensors wirelessly versus having to walk up and physically attach a reader unit.
His thought started the same as ours – put them on WiFi! But adding WiFi coverage across his entire vineyard was not going to be cost-effective. After experimenting with various communication schemes, he has settled on LoRa. Designed to trade raw bandwidth for long range with low power requirements, it is a perfect match for a network of soil moisture sensors.
In the video [Reinier] gives an overview of LoRa for those who might be unfamiliar. Followed by results of his experiments integrating LoRa functionality into Vinduino, and ending with a call to action for hackers to help grow the LoRa network. It sounds like he’s become quite the champion for the cause! He’s even giving a hands-on workshop at Supercon where you can build your own LoRa connected sensor. (Get tickets here.)
We’re always happy to see open-source hardware projects like Vinduino succeed, transitioning to a product that solve real world problems. We know there are even more promising ideas out there, which is why Hackaday’s sister company Tindie is funding a Project to Product program to help this year’s winners follow in Vinduino’s footsteps. We look forward to sharing more success stories yet to come.
LoRa is the new hotness in low-power, long-range communications. Wanting to let the packets fly, [Xose] was faced with a frequecny problem and ended up developing a Europe-friendly LoRa module for the M5Stack system. The hardware is aimed at getting onto The Things Network, a LoRa based network that provides connectivity for IoT devices. While there was an existing M5Stack module for LoRa, it only supported 433 MHz. Since [Xose] is in Europe, an 868 MHz or 915 MHz radio was needed. To solve this, a custom board was built to connect the HopeRF RFM69 series of modules to the M5Stack.
If you haven’t heard of it before, the M5Stack platform is a stackable development board platform. Like Arduino, you can add functionality by stacking PCBs using a standard header. Unlike Arduino, M5Stack fits in a case nicely and is designed for building devices with user interfaces. For $35, you get an ESP32 based system with WiFi, Bluetooth, a color LCD, battery, buttons, a speaker, and IO connectors.
With the hardware in place, [Xose] 3D printed a custom case to hold the board and added it to the stack. The firmware acts as a monitor for The Things Network, showing live coverage. The final product looks very clean for a prototype, maintaining the finished look of M5Stack.
The firmware, board design, and case design files for the project are all available on Github.
There are a multitude of radio shields for the Arduino and similar platforms, but they so often only support one protocol, manufacturer, or frequency band. [Jan Gromeš] was vexed by this in a project he saw, so decided to create a shield capable of supporting multiple different types. And because more is so often better, he also gave it space for not one, but two different radio modules. He calls the resulting Swiss Army Knife of Arduino radio shields the Kite, and he’s shared everything needed for one on a hackaday.io page and a GitHub repository.
Supported so far are ESP8266 modules, HC-05 Bluetooth modules, RFM69 FSK/OOK modules, SX127x series LoRa modules including SX1272, SX1276 and SX1278, XBee modules (S2B), and he claims that more are in development. Since some of those operate in very similar frequency bands it would be interesting to note whether any adverse effects come from their use in close proximity. We suspect there won’t be because the protocols involved are designed to be resilient, but there is nothing like a real-world example to prove it.