Hackaday Prize Entry: A Community Mesh Network

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.

Invention Killed The Inventor

The desire to innovate and change the world can drive one to take dangerous risks. Sometimes, inventors pay the ultimate price. Inventors can be early testers of a device under development, and sometimes pushing the limits of what’s possible has deadly consequences. In this era of warning labels on coffee cups, it’s perhaps worth taking a look back at some inventors of the past who lost their lives in the pursuit of building something new.

Continue reading “Invention Killed The Inventor”

DIY Induction Soldering Iron

[Kasyan TV] shows us how to make a really simple DIY induction soldering iron complete with DIY soldering tips.

This is a pretty cool project. Most of us are used to temperature controlled ceramic heating elements, but there are other ways to get those irons up to temperature. Using scraps from older, presumably broken, soldering irons and some pieces of copper and iron along with a thermocouple for temperature management, [Kasyan TV] manages to throw together an Inductively heated soldering iron. To insulate the coil from the iron they use Kapton tape. The video goes on to show how to make your own induction iron, although missing is a power supply. We are sure a quick eBay search for an induction heater module should bring up something suitable to power the iron, or you could just wait and watch the their next video that will go over power supplies. The soldering tips are simply made from thick copper wire sculpted into the correct shape.

There are advantages to using a soldering iron like this, for example they are pretty durable and will take a knock or two, Our concern is that magnetically sensitive parts may not be happy, and the iron might destroy what you are trying to build. Either way we’ve put the video below the break, so take a look.

Hackaday has featured a few different DIY soldering irons and some pretty cool DIY Soldering Stations over the years. What is your soldering iron of choice and why?

Continue reading “DIY Induction Soldering Iron”

FPGA Rescues Scope From The Dumpster

I’m always on the lookout for a quality addition to my lab that would respect my strict budget. Recently, I’ve found myself pushing the Hertz barrier with every other project I do and hence desperately wanted a high bandwidth scope. Unfortunately, only recently have 70 MHz to 100 MHz become really affordable, whilst a new quad channel oscilloscope in the 500 MHz to 1 GHz range still costs a fortune to acquire. My only option was to find an absolute miracle in the form of an old high bandwidth scope.

It seemed the Gods of Hand Me Down electronics were smiling upon me when I found this dumpster destined HP 54542C. It appeared to be in fairy good shape and was the Top Dog in its day. But something had to be broken right? Sure enough, the screen was clearly faulty and illegible. Want to know how I fixed it? Four letters: FPGA.

Continue reading “FPGA Rescues Scope From The Dumpster”

Simulating VR Obstacles With Wheelchair Brakes

[Joey Campbell] is studying for his PhD at the Bristol Interaction and Graphics Lab, focusing on the interplay between real and virtual objects within the realm of exergaming–“gamercising” where physical motion and effort drives the game. The goal is to make the physical effort seem to correspond with what’s seen on the headset.

[Joey] set up a test rig where an exercise bike’s gears were adjusted based on the terrain encountered, seeking to find out if that realism inspired a greater feeling of immersion. He also provided some test subjects a HUD with their heart rate and other stats, to see if that encouraged gamers to exercise more.

In his current project, [Joey] has equipped a wheelchair with a pair of Arduino-controlled servos that squeeze the brakes to simulate an obstacle. In the VR realm, a player pushes the wheelchair toward a virtual block and the brakes engage, requiring the player push harder to bypass the obstacle.

One imagines the possibilities of games designed for specifically for wheelchairs. The Eyedrivomatic wheelchair that won the 2015 Hackaday Prize sounds perfect for the job!

Continue reading “Simulating VR Obstacles With Wheelchair Brakes”

Current Sink Keeps The Smoke In

One of the most versatile tools on anyone’s work bench, at least as far as electrical projects are concerned, is a power supply. Often we build our own, but after we’ve cobbled together some banana jacks with a computer’s PSU or dead-bug soldered a LM317 voltage regulator to a wall wart, how will that power supply perform? Since it’s not desirable to use a power supply that’ll let the smoke out of everything it powers (or itself, for that matter) a constant current sink, or load, can help determine the operating limits of the power supply.

[electrobob] built this particular current sink from parts he had lying around. The theory of a constant current sink is relatively straightforward so it’s easily possible to build one from parts out of the junk drawer, provided you can find a few transistors, fuses, an op amp, and some heat sinks. The full set of schematics that [electrobob] designed can be found on his main project page. He’s also gone a step further with this build as well, since he shorted out his first prototype and destroyed some of the transistors. But, using a few extra transistors in his design also improves the safety and performance of the load, so it’s a win-win.

This constant current load also has the added feature of being able to interface with a waveform generator (an Analog Discovery, specifically) and as a result can connect and disconnect the load quickly. If you aren’t in need of an industrial-grade constant current sink and you have some spare parts lying around, this would be a great one to have around the work bench.

Shoot Video In 26 Different Directions

[Mark Mullins] is working on a project called Quamera: a camera that takes video in every direction simultaneously, creating realtime 3D environments on the fly.

[Mark] is using 26 Arducams, arranging them in a rhombicuboctahedron configuration, which consists of three rings of 8 cameras with each ring controlled by a Beaglebone; the top and bottom rings are angled at 45 degrees, while the center ring looks straight out. The top and bottom cameras are controlled by a fourth Beaglebone, which also serves to communicate with the Nvidia Jetson TX1 that runs everything. Together, these cameras can see in all directions at once, with enough overlap for provide a seamless display for viewers.

In the image to the right, [Mark] is testing out his software for getting the various cameras to work together. The banks of circles and the dots and lines connecting to them represent the computer’s best guess on how to seamlessly merge the images.

If you want to check out the project in person, [Mark] will be showing off the Quamera at the Dover Mini Maker Faire this August. In the meantime, to learn more about the Jetson check out our thorough overview of the board.