The idea here is pretty simple: use a remote temperature sensor to tell a fan located behind the fireplace when it’s time to kick on and start sharing some of that warmth with the rest of the house. But as usual, it ended up being a bit trickier than anticipated. For one, when [Ben] took a close look at the Vornado 660 fan he planned on using, he realized that its speed controller was “smart” enough that simply putting a relay on the AC line wouldn’t allow him to turn it on and off.
So he had to do some reverse engineering to figure out how the Sonix SN8P2501B microcontroller on the board was controlling the fan, and then wire the Photon directly to the pins on the chip that corresponded with the various physical controls. This allows the Photon to not only “push” the buttons to trigger the different speeds, but also read the controls to see if a human is trying to override the current setting.
For the remote side [Ben] is using a Particle Xenon, which is specifically designed for Internet of Things endpoints and sensor applications. Combined with a TMP36 temperature sensor and 3.7 V 500 mAh battery, this allowed him to easily put together a wireless remote thermometer that will publish the current temperature to the Photon’s mesh network at regular intervals.
5G is gearing up to be the most extensive implementation of mesh networking ever, and that could mean antennas will not need to broadcast for miles, just far enough to reach some devices. That unsightly cell infrastructure stuck on water towers and church steeples could soon be hidden under low-profile hunks of metal we are already used to seeing; manhole covers. This makes sense because 5G’s millimeter radio waves are more or less line-of-sight, and cell users probably wouldn’t want to lose connectivity every time they walk behind a building.
At the moment, Vodafone in the UK is testing similar 4G antennas and reaching 195 megabits/sec download speeds. Each antenna covers a 200-meter radius and uses a fiber network because, courtesy of existing underground infrastructure. There is some signal loss from transmitting and receiving beneath a slab of metal, but that will be taken into account when designing the network. The inevitable shift to 5G will then be a relatively straightforward matter of lifting the old antennas out and laying the new hardware inside, requiring only a worker and a van instead of a construction crew.
The AND!XOR team have somehow managed to outdo themselves once again this year. Their newest unofficial hardware badge for DEF CON 26 just arrived. It’s a delightful creation in hardware, software, and the interactive challenges built into both.
They call this the “Wild West of IoT”, a name that draws from the aesthetic as well as the badge-to-badge communications features. Built on the ESP32-WROVER module which brings both WiFi and Bluetooth to the party, the badges are designed to form a wireless botnet at the conference. Anyone with a badge can work to advance their level and take more and more control of the botnet as they do.
Check out the video overview and then join me below for a deeper dive into all this badge has to offer.
The Meshpoint project originated in Croatia during the 2015 Syrian refugee crisis, when [Valent Turkovic] and other volunteers noticed that first responders, including NGOs like Greenpeace and the Red Cross, often struggled to set up communications in the field. They came to the conclusion that they couldn’t rely on the normal communications infrastructure because it was either damaged or overloaded.
The solution is a net of open source, autonomous WiFi mesh routers, scalable from a single team to serving thousands of people. Responders who won’t have time for a difficult login process, should find setup as easy as signing in to a social media site.
The physical nodes would consist of a router robust for up to 150 connections, all run by an ESP8266 and protected by a weatherproof enclosure. They would feature 6-8 hour battery lives with recharging via solar/wind, AC from wall current or generators, or simply DC car batteries.
In just two weeks, we’ll be flooding into the casinos of Las Vegas for DEF CON. By far our favorite part is the unofficial hardware badges which make their way to the con each year. The AND!XOR team has put together an incredible offering this year with what I’m calling the “Bender on a Bender” badge. They sent us two of them, so let’s jump right in and see what this badge is all about.
While the Internet of Things is here to stay, and will kill us all, there are a few places left on the planet that will remain unscathed during the robot uprising. These underserved communities still have a need for communications and networking, leading [hlew] to create a Community Engagement Mesh Network as an entry for The Hackaday Prize.
While there are many, many options available for DIY networking solutions out there today, [hlew] is leaning on some work done by some of [Bruce Land]’s students at Cornell. This project used simple and cheap nRF24 radio modules for a true mesh network with multi-node communication, dynamic route discovery, and dynamic route reconfiguration.
The CEMN will rely on this network to provide communications to underserved communities. The primary goal of this network is to broadcast information like crop reports and health advisories, but it can also be used for peer to peer communications between individuals.
Wireless networks have been reduced to a component, for most of us. We fit a device, maybe an ESP8266 module or similar, and as if by magic a network exists. The underlying technology has been abstracted into the firmware of the device, and we never encounter it directly. This is no bad thing, because using wireless communication without having to worry about its mechanics gives us the freedom to get on with the rest of our work.
It is however interesting once in a while to take a look at the operation of a real wireless network, and [Alex Wong], [Brian Clark], and [Raghava Kumar] have given us a project with the opportunity to do just that. Their PIC Mesh university project is a distributed wireless mesh network using 2.4GHz NRF24L01 transceiver modules and PIC32 microcontrollers. They have it configured for demonstration purposes with a home automation system at the application layer, however it could be applied to many other applications.
The real value in this project is in its comprehensive but easy to read write-up of the kind you’d expect from a university project. The front page linked above has an overview of how the mesh works, but there are also pages taking us through the hardware, the networking software layer, and the home automation application layer. If you have ever wanted to understand a simple mesh networking system, this is a good place to start.