Farm Data Relay System: Combine LoRa And 2.4 Ghz Networks Without WiFi Routers And Cloud Dependence

July 2, 2022 by Danie Conradie 25 Comments

Setting up a wireless sensor network over a wide area can quickly become costly, and making everything communicate smoothly can be a massive headache, especially when you’re combining short range Wi-Fi with long range LoRa. To simplify this, [Timm Bogner] created Farm Data Relay System which simplifies the process of combining LoRa, 2.4Ghz modules and serial communications in various topologies over wide areas.

The FDRS uses a combination of ESP32/8266 sensor nodes for short range, and LoRa nodes for long range. The ESP nodes use Espressif’s connectionless ESP-NOW peer-to-peer protocol on which allow multiple ESP boards to communicate directly without the need for a Wi-Fi router. The ESP modules can have one of 3 roles, nodes, repeaters or gateways, and gateways and repeaters share the same code. Nodes take sensor inputs, and are configured to each have a unique READING_ID.

Relays just retransmit ESP-NOW packets to extend the network range, while gateways convert packets between ESP-NOW, MQTT over Wi-Fi, LoRa or serial messages as required. Repeaters and gateways each have a unique UNIT_MAC for addressing. The code that handles communication for the ESP devices is simple and well documented, so you only need to set a few configuration values, and then can focus your efforts on the code required for your specific application.

The hub of the system is a Raspberry Pi running Node-RED which acts as the final MQTT gateway and connects to the ESP MQTT gateways. This means that all the action happens in the local network, without being dependent on an internet connection and cloud service. However, it can still send and receive data over the internet using MQTT or any other protocol as required. Node-RED makes it particularly easy to build custom automations and interfaces.

In the video after the break, Andreas Spiess, the man with the Swiss accent, who also has a hand in the project, goes over all the features, setup and caveats.

Continue reading “Farm Data Relay System: Combine LoRa And 2.4 Ghz Networks Without WiFi Routers And Cloud Dependence” →

Designing A LoRa Gateway During A Part Shortage

June 28, 2022 by Tom Nardi 14 Comments

It’s fair to say that right now is probably the worst possible time you could choose to design a new piece of hardware. Of course the reality is that, even in the middle of a parts shortage that’s driving the cost of many components through the roof (if you can even find them), we can’t just stop building new devices. In practice, that means you’ll need to be a bit more flexible when embarking on a new design — it’s like the Stones said: “You can’t always get what you want / But if you try sometime you’ll find / You get what you need”

For [Ryan Walmsley], that meant basing his new outdoor LoRa gateway on the ubiquitous Raspberry Pi was a non-starter. So what could he use in its place? The software situation for the Nano Pi Duo looked pretty poor, and while the Onion Omega 2+ was initially compelling, a bug in the hardware SPI seemed to take it out of the running. But after more research, he found there was a software implementation that would fit the bill. Continue reading “Designing A LoRa Gateway During A Part Shortage” →

a 3D-rendered image of a PCB with several knobs and buttons

Odd Inputs And Peculiar Peripherals: The LowPow ShortKeyboard Can Work On Your Desk Or Out In The Field

June 28, 2022 by Robin Kearey 1 Comment

For some power users, the one-hundred-and-something keys on regular keyboards just aren’t enough for their everyday tasks. Macro keypads are a popular way of extending one’s input capabilities, and there are almost as many examples as there are power users. [Ulrich]’s latest project, dubbed the LowPow E-Ink ShortKeyboard, is a beautiful and meticulously documented design for a macro pad that includes several unusual features.

Built around an ESP32-S3 microcontroller, the ShortKeyboard features nine programmable function keys plus an analog joystick and a rotary encoder. The keys are based on Cherry MX RED types commonly seen in mechanical keyboards, illuminated from below by by miniature RGB LEDs. A big e-ink display in the middle can be used to show the function of each key.

Continue reading “Odd Inputs And Peculiar Peripherals: The LowPow ShortKeyboard Can Work On Your Desk Or Out In The Field” →

Long-Distance Text Communication With LoRa

May 25, 2022 by Bryan Cockfield 50 Comments

Affordable and reliable cell phones have revolutionized the way we communicate over the last two decades or so, and this change was only accelerated by the adoption of the smartphone. This is all well and good if you’re living in a place with cellular infrastructure, but if you’re in more remote areas you’ll have to be a little more inventive. This text-based communications device, for example, lets you send text messages without all of that cumbersome infrastructure.

While [Arthur] didn’t create this project specifically for off-grid use, it’s an interesting project nonetheless. The devices use a physical QWERTY keyboard and a small screen, reminiscent of BlackBerry devices from the late 2000s (partially because they are actually using BlackBerry keyboards). One of the other goals for this project was low power consumption, and between polling the keyboard, the memory LCDs, and receiving and transmitting messages using LoRa, [Arthur] was able to get the current draw down to 12 mA.

Between the relatively common nRF52840 and SX1262 chips, plus the fact that [Arthur] made the schematics available, this makes for an excellent off-grid device for anyone who likes to drive off into the wilderness or lives far enough outside of town that cell phone reception is a concern.

Looking for something a little easier to put together before your upcoming camping trip? This similarly styled LoRa communicator from [MSG] uses off-the-shelf modules to greatly reduce the part count. Another option for off-grid communications is to use existing smartphones paired with a LoRa network like we saw in this project.

LoRa-Powered Birdhouses Enable Wireless Networking When The Internet’s Down

April 9, 2022 by Robin Kearey 26 Comments

One of the design requirements for the networks that evolved into the Internet was the ability to keep functioning, even if some nodes or links were disabled or destroyed in war. The packet-switched architecture that still powers today’s Internet is a direct result of that: if one link stops functioning, information is automatically re-routed towards its intended destination. However, with tech giants occupying increasingly large parts of the global internet, an outage at one of them might still cause major disruption. In addition, a large-scale power interruption can disable large parts of the network if multiple nodes are connected to the same grid.

Six pieces of wood, with a hammer next to them — Just six pieces of wood make up the birdhouse.

Enter the LoRa Birdhouse project by the Wellesley Amateur Radio Society that solves those two problems, although admittedly at a very small scale. Developed by amateur radio operators in eastern Massachusetts, it’s basically a general-purpose LoRa-based packet-switching network. As it’s based on open-source hardware and commonly available components, its design allows anyone to set up a similar network in their own area.

The network is built from nodes that can receive messages from their neighbors and pass them on towards their final destination. Each node contains a Semtech SX1276 transceiver operating in the 902-928 MHz band, which gets its data from an ESP32 microcontroller. The nodes are placed in strategic locations outside and are powered by solar panels to reduce their ecological footprint, as well as to ensure resilience in case of a power outage. To make the whole project even more eco-friendly, each node is built into a birdhouse that provides shelter to small birds.

Users can access the network through modified network nodes that can be hooked up to a PC using a USB cable. Currently, a serial terminal program is the only way to interact with the network, although a more user-friendly interface is being planned. FCC rules also require all users (except any avian residents) to be licensed amateur radio operators, and all traffic to remain unencrypted. Tests have shown that one kilometer between nodes can work in the right conditions, enabling the deployment of networks across reasonably large areas.

While the Birdhouse Network might not be a plug-and-play internet replacement in case of a nuclear apocalypse, it does provide an excellent system to experiment with packet-switching wireless network technology. We’ve seen similar LoRa-based network initiatives like Qmesh, Cellsol and Meshtastic, all of which provide some way to communicate wirelessly without requiring any centralized hardware.

Low Power Mode For Custom GPS Tracker

March 28, 2022 by Bryan Cockfield 19 Comments

GPS has been a game-changing technology for all kinds of areas. Shipping, navigation, and even synchronization of clocks have become tremendously easier thanks to GPS. As a result of its widespread use, the cost of components is also low enough that almost anyone can build their own GPS device, and [Akio Sato] has taken this to the extreme with efforts to build a GPS tracker that uses the tiniest amount of power.

This GPS tracker is just the first part of this build, known as the air station. It uses a few tricks in order to get up to 30 days of use out of a single coin cell battery. First, it is extremely small and uses a minimum of components. Second, it uses LoRa, a low-power radio networking method, to communicate its location to the second part of this build, the ground station. The air station grabs GPS information and sends it over LoRa networks to the ground station which means it doesn’t need a cellular connection to operate, and everything is bundled together in a waterproof, shock-resistant durable case.

[Akio Sato] imagines this unit would be particularly useful for recovering drones or other small aircraft that can easily get themselves lost. He’s started a crowdfunding page for it as well. With such a long battery life, it’s almost certain that the operator could recover their vessel before the batteries run out of energy. It could also be put to use tracking things that have a tendency to get stolen.

An Off-Grid Makeshift Cell Network

February 21, 2022 by Bryan Cockfield 51 Comments

When traveling into the wilderness with a group of people, it’s good to have a method of communications set up both for safety and practicality. In the past people often relied on radios like FRS, CB, or ham bands if they had licenses, but nowadays almost everyone has a built-in communications device in their pocket that’s ready to use. Rather than have all of his friends grab a CB to put in their vehicle for their adventures together, [Keegan] built an off-grid network which allows any Android phone to communicate with text even if a cell network isn’t available.

The communications system is built on the LoRa communications standard for increased range over other methods like WiFi using a SX1278 chip and an ESP8266. The hardware claims a 10 km radius using this method which is more than enough for [Keegan]’s needs. Actually connecting to the network is only half of the solution though; the devices will still need a method of communication. For that, a custom Android app was created which allows up to 8 devices to connect to the network and exchange text messages with each other similar to a group text message.

For off-grid adventures a solution like this is an elegant solution to a communications problem. It uses mostly existing hardware since everyone carries their own phones already, plus the LoRa standard means that even the ESP8266 base station and transmitter are using only a tiny bit of what is likely battery power. If you’re new to this wireless communications method, we recently featured a LoRa tutorial as well.