Uplink System For High-Altitude Balloons

April 9, 2021 by Maya Posch 10 Comments

Most uses of high-altitude balloons are fairly simple: send balloon up, have it beam down measurements and images. While this is indeed straightforward, it is also very limiting. This is why [Dave Akerman] has been working on adding to the HAB balloons he regularly flies. This builds on the work [Dave] did back in 2015 with adding LoRa transceiver RF communication.

Since LoRa transceivers are by definition capable of bidirectional communication, this was very useful for adding simple but essential features such as retransmission of data in case e.g. part of some image or telemetry data is missing. Other interesting things one can do with bidirectional transmission include controlling individual balloons, and having them transmit or relay information between balloons.

A tricky thing which [Dave] describes in the blog post is making sure that both ends of the connection are actually listening using timing settings. The use of encryption is also strongly recommended, unless you want to risk someone hijacking your balloons. This has now all been implemented in the HAB Explora app for Android, as well as the application for Windows.

Header image: Antonino Vara, CC BY 4.0.

LoRa Messenger Does Its Best BlackBerry Impression

February 5, 2021 by Tom Nardi 23 Comments

While the de facto smartphone design ultimately went in a different direction, there’s no denying the classic BlackBerry layout offered some compelling advantages. It was a gadget primarily designed to send and receive emails and text messages, and it showed. So is it really any wonder [MSG] would build his pocket-sized LoRa messengers in its image?

Of course, he did have some help. The communicators use the Keyboard FeatherWing by [arturo182], which puts a surplus BlackBerry Q10 keyboard on a custom PCB designed to accept a board from Adafruit’s Feather collection. [MSG] ended up pairing his with a Feather M4 because he wanted to work with CircuitPython, with a 900 MHz LoRa FeatherWing along for the ride. He notes that switching his code over to Arduino-flavored C would allow him to use the Feather M0 that features integrated LoRa; a change that would allow him to make the gadget a bit thinner.

Inside the 3D printed enclosure, He’s made room for a 3.7 V 1800 mAh pouch battery that should provide plenty of runtime. There’s also an external antenna with a uFL pigtail for connecting to the radio. The case is held together with heat-set inserts, which should make it more than robust enough to handle a few adventures.

[MSG] says slight variations in hardware versions means his STLs might need a little tweaking to fit your components, and warns that his code is basically just a mashup of examples he found online, but he’s still sharing the goods for anyone who wants to reach out and touch someone without all that pesky infrastructure in the way.

Continue reading “LoRa Messenger Does Its Best BlackBerry Impression” →

ExpressLRS: Open Source, Low Latency, Long Range RC Protocol

January 19, 2021 by Danie Conradie 42 Comments

One of the major choices a newcomer to the RC flying hobby must make is on the RC link protocol. To add the list of choices (or confusion) there is now a new open-source, low latency, and long-range protocol named ExpressLRS.

ExpressLRS’s claim to fame is high packet rates of up to 500 Hz, with plans for 1000 Hz, and latency as low as 5 ms. Long-range testing has pushed it out to 30 km with a flying wing (video below), but this is not unheard of for other protocols. Most modern RC protocols run either in the 2.4 GHz or 915/868 MHz bands, with the latter having a definite advantage in terms of range.

ExpressLRS has options to run on either band, using Semtech SX127x (915/868 MHz) or SX1280 (2.4 GHz) LoRa transceivers, connected to STM32, ESP32, or ESP8285 microcontrollers. The ESP microcontrollers also allow software updates over Wi-Fi.

We’re excited to see an open-source competitor to the proprietary protocols currently dominating the market, but several open-source protocols have come and gone over the years. Hardware availability and compatibility is a deciding factor for a new protocol’s success, and ExpressLRS already has an advantage in this regard. Existing Frsky R9 transmitters and receivers, and Immersion RC Ghost receivers are compatible with the firmware. There are also DIY options available, and the GitHub page claims that several manufacturers are working on official ExpressLRS hardware.

If you’re already into the RC hobby, and you have compatible hardware lying around, be sure to give it a try and give some feedback to the developers! One scenario we would like to see tested is high interference and congested band conditions, like at RC flying events.

All the source code and hardware designs are available on GitHub, and there are active community discussions on Discord. Continue reading “ExpressLRS: Open Source, Low Latency, Long Range RC Protocol” →

IRC Over LoRa, For When Things Really Go South

December 12, 2020 by Tom Nardi 74 Comments

As a society, we’ve become accustomed to always-on high-speed data connections, whether we’re at home on the computer or out and about with a mobile device. But what happens if a natural disaster knocks out the local infrastructure? Sure some people will be able to fire up their radio if they need to reach out and touch someone, but even among hackers, hams are a minority. What we really need is a backup Internet.

The team behind the CellSol project hopes to show that building a volunteer-operated distributed communications network is not only within the capabilities of the hacker community but probably much easier and cheaper to do than you might think. Each node in the network, known as a Pylon in CellSol parlance, can shuttle data between the LoRa backbone and WiFi-enabled devices like smartphones and computers. Once the network is up and running, users don’t need any special hardware or software to use it.

Now to be clear, nobody is talking about surfing the web here. When a user connects to one of the ESP32 Pylons, they’ll be able to access a simplistic chat system through their browser. If the Pylon has an active Internet connection the chat can be bridged to an IRC channel. Without Internet connectivity, the pylon will simply give users on the CellSol network a means to communicate among each other. To keep things simple there’s no user names, private messages, or encryption. This is bare-bones, end-of-the-world style communication.

Want to join the CellSol revolution? All you really need is an ESP32, a LoRa radio, and the open-source firmware. If you get something like the Heltec LoRa 32 development board, you don’t even need to solder anything together. Just flash the board and go. Once you have a few Pylons going, you can also put together a cheap repeater node using a LoRa equipped Arduino. Both devices are small and energy efficient enough that they could easily be battery or solar powered. As you can see in the video after the break, the team even envisions a future where they could be dropped off in public areas via drone.

This isn’t the first time we’ve seen the ESP32 used to establish an off-grid LoRa communications network, and like those previous attempts, it’s usefulness will largely depend on how many people you can convince to set up their own nodes and repeaters. But if you’ve got some open minded friends who live relatively close by, this could be a great way to have a little chat.

Continue reading “IRC Over LoRa, For When Things Really Go South” →

Weather Warnings And Dust Detection From This Meteorological Marvel

September 14, 2020 by Brian McEvoy 4 Comments

We love getting our weather in a flurry of different methods, but have you tried building your own sensor suite to harvest the data for you? [Giovanni ‘CyB3rn0id’ Bernardo] needed to monitor isolated locations outside the reach of WiFi. His ray of hope is an ESP32 controller coupled with a LoRa module to beam data to a remote station that can access the cloud.

In addition to radios, he poured a deluge of sensors into the base station to read the temperature, barometric pressure, humidity, and fine dust. Why monitor dust as part of weather data collection? Particulate matter has a huge effect on air quality, something of great interest during a respiratory pandemic. For those readers near wildfires, quantifying your air quality (both indoors and out) is certainly of interest. [Giovanni] is using an SDS011 air quality sensor and has a long writeup just on this part. It uses a fan to move air past a laser-based sensing mechanism.

At the base station, live readings are shown on an OLED screen, but you can also connect to the ESP32 through your phone like a hotspot. If you keep a memory card installed, it will cache the readings in a perpetually-updated CSV file. In regular operation, the LoRa module overcasts the telemetry to its sister unit that acts as a Wifi/LoRa bridge so anyone can view gauges and graphs in real-time on ThingSpeak.

We want to shower [CyB3rn0id] with praise for seeing the ~~cirrus~~ serious impact of harmful dust and making something that can alert people. We don’t want to rain on anyone’s parade, but sometimes it is better to stay inside.

The Open Source Mars Rover, One Year Later

July 2, 2020 by Tom Nardi 18 Comments

As the name implies, here at Hackaday we strive to bring you interesting projects every single day. But that doesn’t necessarily mean a project only gets one day to grace these storied pages. Quite the opposite, in fact. We’re always happy to revisit a project and find out how far it’s evolved since we last crossed paths with it, especially when the creators themselves reach out to give us an update.

Which is exactly what happened when [Jakob Krantz] recently wrote in to get us up to speed on this incredible open source rover project. We first saw this 3D printed Curiosity inspired robot a little less than a year ago, and at that point it was essentially just a big box with the distinctive NASA rocker-bogie suspension bolted on. Now it not only looks a lot closer to the Martian rovers that inspired it, but it’s also learned a number of new tricks that really take this project to the next level.

The articulated head and grabber arm don’t just help sell the Curiosity look, they’re actually functional. [Jakob] notes that he doesn’t have kinematics integrated yet, so moving the arm around is more for show than practical application, but in the future it should be able to reach out and grab objects. With the new cameras in the head, he’ll even be able to get a first person view of what he’s picking up.

Last year [Jakob] was using a standard RC transmitter to drive the rover around, but he’s since put together a custom controller that’s truly a thing of beauty. It uses an ESP32 and LoRa module to communicate with matching hardware inside the rover, as well as a smartphone clipped onto the top that’s displaying telemetry and video over WiFi. The controller is actually its own separate project, so even if you aren’t in the market for a scaled down Mars rover, its controller could come in handy for your next robotics project.

Presumably the multi-mission radioisotope thermoelectric generator (MMRTG) on the back of the rover is just pretend….but with this guy, we’re not so sure. Give him another year, and who knows.