LoRa-Based Plant Monitoring

September 23, 2019 by Sharon Lin 28 Comments

Croatian engineers [Slaven Damjanovic] and [Marko Čalić] have developed a wireless system for farmers to monitor plant conditions and weather along their agricultural fields. The system uses an RFM95W module for LoRa communication, and devices are designed to be plug-and-play, battery-powered, and have long-range communication (up to 10km from the gateway).

It uses an ATMega328 microprocessor, and includes sensors for measuring soil moisture (FC28 sensor), leaf moisture (FC37 sensor), pressure (BME280 sensor), and air temperature and humidity (DHT22 or SHT71 sensor). The data is sent to a multichannel The Things Network gateway that forwards the information to an external database, which then displays the data through a series of graphs and tables.

The software for sending messages to the gateway is based on the LoRa MAC in C (LMIC) and LowPower libraries and was developed by [ph2lb].

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Handheld LoRa Joystick For Long-Range Bots

September 11, 2019 by Tom Nardi 11 Comments

Wanting a simple tool to aid in the development of LoRa controlled robotic projects, [Jay Doscher] put together this very slick one-handed controller based on the 900 MHz Adafruit Feather M0. With a single trigger and a miniature analog joystick it’s a fairly simple input device, but should be just enough to test basic functionality of whatever moving gadget you might find yourself working on.

Wiring for this project is about as simple as you’d expect, with the trigger and joystick hanging off the Feather’s digital ports. The CircuitPython code is also very straightforward, though [Jay] says in the future he might expand on this a bit to support LoRaWAN. The controller was designed as a barebones diagnostic tool, but the hardware and software in its current form offers an excellent opportunity to layer additional functionality on a known good base.

Everything is held inside a very well designed 3D printed enclosure which [Jay] ran off on his ELEGOO Mars, one of the new breed of low-cost resin 3D printers. The machine might be pretty cheap, but the results speak for themselves. While resin printing certainly has its downsides, it’s hard not to be impressed by the finish quality of this enclosure.

While LoRa is generally used for transmitting small bits of information over long distances, such as from remote sensors, this isn’t the first time we’ve seen it used for direct control of a moving object. If you’re not up to speed on LoRa, check out this excellent talk from [Reinier van der Lee] that goes over the basics of the technology and how he used it to build a community sensor network.

Hackaday Links: August 4, 2019

August 4, 2019 by Dan Maloney 22 Comments

Is the hacking community facing a HOPEless future? It may well be, if this report from 2600 Magazine is any indication. The biennial “Hackers On Planet Earth” conference is in serious financial jeopardy after the venue that’s hosted it for years, the Hotel Pennsylvania in Manhattan, announced a three-fold increase in price. Organizers are scrambling to save the conference and they’re asking for the community’s help in brainstorming solutions. Hackaday was at HOPE XI in 2016 and HOPE XII in 2018; let’s HOPE we get to see everyone again in 2020.

If you’ve ever been curious about how a 1970s PROM chip worked, Ken Shirriff has you covered. Or uncovered, as he popped the top off a ceramic MMI 5300 DIP to look at the die within. Closeups of the somewhat cockeyed die reveal its secrets – 1,024 tiny fusible links. Programming was a matter of overloading a particular fuse, turning a 1 into a 0 permanently. It’s a fascinating look at how it used to be done, with Ken’s usual attention to detail in the documentation department.

We had a great Hack Chat this week with Mihir Shah from Royal Circuits. Royal is one of the few quick-turn PCB fabs in the USA, and they specialize in lightning-fast turnaround on bare PCBs and assembled boards. He told us all about this fascinating business, and dropped a link to a side project of his. Called DebuggAR, it’s an augmented reality app that runs on a smartphone and overlays component locations, signal traces, pinouts, and more right over a live image of your board. He’s got a beta going now for iPhone users and would love feedback, so check it out.

With all the cool things you can do with LoRa radios, it’s no wonder that wireless hobbyists have taken to pushing the limits on what the technology can do. The world record distance for a LoRa link was an astonishing 702 km (436 miles). That stood for two years until it was topped, twice in the same day. On July 13th, the record was pushed to 741 km, and a mere five hours later to 766 km. All on a scant 25 mW of power.

Linux distro Manjaro made an unconventional choice regarding which office suite to include, and it’s making some users unhappy. It appears that they’ve dumped LibreOffice from the base install, opting instead to include the closed-source FreeOffice. Worse, FreeOffice doesn’t have support for saving .doc and OpenDocument files; potentially leaving LibreOffice users stranded. Paying for an upgrade to SoftMaker’s Office product can fix that, but that’s hardly free-as-in-beer free. It’s kind of like saying the beer is free, but the mug is an upgrade. UPDATE: It looks like the Manjaro team heard all the feedback and are working on a selector so you can install the office suite of your choice.

Tragic news out of New Hampshire, as amateur radio operator Joe Areyzaga (K1JGA) was killed while trying to dismantle an antenna tower. Local news has coverage with no substantial details, however the hams over on r/amateurradio seem to have the inside line on the cause. It appears the legs of the tower had filled with water over the years, rusting them from the inside out. The tower likely appeared solid to Joe and his friend Mike Rancourt (K1EEE) as they started to climb, but the tower buckled at the weak point and collapsed. K1EEE remains in critical condition after the 40′ (12 m) fall, but K1JGA is now a silent key. The tragedy serves as a reminder to everyone who works on towers to take nothing for granted before starting to climb.

And finally, just for fun, feast your eyes on this movie of the ESA’s Rosetta spacecraft as is makes its flyby of comet 67P/Churyumov–Gerasimenko. It’s stitched together from thousands of images and really makes 67P look like a place, not just a streak of light in the night sky.

High-Tech Alms Collection With The ESP32

July 17, 2019 by Tom Nardi 2 Comments

In an ideal world, shop space, tools, and components would be free. But until we get to that Star Trek utopia, hackerspaces will have to rely on donations from the community to help stay afloat. While asking for money, at least you can have some fun with it if you design and build an Internet-connected donation box.

Or at least that’s how [Goran Mahovlic] handled it for the Radiona hackerspace in Zagreb, Croatia. Not content with just cutting a slit in the top of a shoe box, he came up with a physical donation system that’s not only more informative for those donating, but more organized for those collecting the funds.

The key is a arcade-style programmable coin acceptor from SparkFun. When connected to a microcontroller, this allows the box to keep a running tally on how much money has been inserted. With the use of a RFM96 LoRa module, it can even report on the current haul while remaining mobile; perfect for when the hackerspace has events outside of their home base.

But counting quarters is hardly a task befitting a powerful microcontroller like the ESP32. So [Goran] gave the chip something to do in its spare time by adding a couple of buttons and an LCD. This allows the user to scroll through a list of various projects that are looking for donations, and decide which one they want to financially support. When the donation box counts how much money has been inserted, it records which project its been earmarked for.

Of course, if you’d rather the free market do its thing, we’ve seen this same coin acceptor used to build a locker-sized vending machine. Or if you’re feeling crafty, you could always try your hand at building one with cardboard.

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Adding LoRa Long Range Radio To Smartphones And Connected Devices

July 11, 2019 by Brian Benchoff 41 Comments

Would you add another radio to your smartphone? No, not another WiFi or cellular radio; a smartphone already has that. I’m talking about something that provides connectivity through ISM bands, either 433 or 915 MHz. This can be used where you don’t have cell phone coverage, and it has a longer range than WiFi. This is the idea behind Skrypt, a messaging system that allows you to send off-the-grid messages.

Skrypt is an ESP32-based hardware modem that can communicate with a smartphone, or any other device for that matter, over Bluetooth or USB. Inside, there are two modules, an ESP32 WROOM module that provides the Bluetooth, WiFi, USB connectivity, and all of the important software configuration and web-based GUI. The LoRa module is the ubiquitous RFM95W that’s ready to drop into any circuit. Other than that, the entire circuit is just a battery and some power management ICs.

While LoRa is certinaly not the protocol you would use for forwarding pics up to Instagram, it is a remarkable protocol for short messages carried over a long range. That’s exactly what you want when you’re out of range of cell phone towers — those pics can wait, but you might really want to send a few words to your friends. That’s invaluable, and LoRa makes a lot of sense in that case.

Neural Network Smartens Up A Security System

July 3, 2019 by Lewin Day 11 Comments

It’s all well and good having a security camera recording all the time, but that alone can’t sound the alarm in the event of a crime. Motion sensing is of limited use, often being triggered by unimportant stimuli such as moving shadows or passing traffic. [Tegwyn☠Twmffat] wanted a better security system for the farm, and decided that neural networks would likely do the trick.

The main component of the security system is a Raspberry Pi fitted with a camera and a Movidius Neural Compute Stick. This allows the Raspberry Pi to run real-time object identification on video. The Raspberry Pi is programmed to raise the alarm if it detects humans approaching, but ignores the family dog and other false targets. In the event of a detection, the Raspberry Pi sends a signal over LoRa to a base station, which sounds an alarm. The pitch of the alarm increases the closer the target gets to the camera, thanks to some simple code with bounding boxes.

It’s a nifty way to create an intelligent security system, and all the more impressive for being entirely constructed from off-the-shelf parts and code. Neural networks have become increasingly useful; they can even tell when your cat wants to go outside. Video after the break.

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Storm Chasers Score Bullseye On Tornado With Instrument-Packed Rocket

June 5, 2019 by Dan Maloney 16 Comments

Model rockets are a heck of a lot of fun, and not a few careers in science and engineering were jump-started by the thrilling woosh and rotten-egg stench of an Estes rocket launch. Adding simple instrumentation to the rocket doubles the fun by allowing telemetry to be sent back, or perhaps aiding in recovery of a lost rocket. Sending an instrument-laden rocket into a tornado is quite a few notches past either of those scenarios, and makes them look downright boring by comparison.

A first and hopefully obvious point: just don’t do this. [ChasinSpin] and [ReedTimmer] are experienced storm chasers, and have a small fleet of purpose-built armored vehicles at their disposal. One such vehicle, the Dominator, served as a mobile launch pad for their rocket as they along with [Sean Schofer] and [Aaron Jayjack] chased what developed into an EF4 monster tornado near Lawrence, Kansas on May 28. They managed to score a direct hit on the developing tornado, only 100 feet (30 meters) away at the time, and which took the rocket to 35,000 ft (10.6 km) and dragged it almost 30 miles (42 km) downrange. They lost touch with it but miraculously recovered it from a church parking lot.

They don’t offer a lot of detail on the rocket itself, but honestly it looks pretty much off-the-shelf, albeit launched from an aimable launchpad. [ChasinSpin] does offer a few details on the instrument package, though – a custom PCB with GPS, IMU, a temperature/humidity/barometric pressure sensor, and a LoRa link to send a data packet back every second. The card also supported an SD card for high-resolution measurements at 10 times per second. Check out the launch in the video below, and be sure to mouse around to get a look at the chaotic environment they were working in.

Even if this isn’t as cool as sending a sounding rocket into an aurora, it’s still really cool. We’re looking forward to seeing what kind of data this experiment collected, and what it reveals about the inner workings of these powerful storms.

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