Vampire Charger Is A Rugged Anything-to-5VDC Converter

July 29, 2018 by Donald Papp 43 Comments

USB sockets providing 5 VDC are so ubiquitous as a power source that just about any piece of modern portable technology can use them to run or charge. USB power is so common, in fact, that it’s easy to take for granted. But in an emergency or in the wake of a disaster, a working cell phone or GPS can be a life saver and it would be wise not to count on the availability of a clean, reliable USB power supply.

That’s where the Vampire Charger by [Matteo Borri] and [Lisa Rein] comes in. It is a piece of hardware focused on turning just about any source or power one might possibly have access to into a reliable source of 5 VDC for anything that can plug in by USB. This is much more than a DC-DC converter with a wide input range; when they say it is made to accept just about anything as an input, they mean it. Found a working power source but don’t know what voltage it is? Don’t know which wire is positive and which is negative? Don’t even know whether it’s AC or DC? Just hook up the alligator clips and let the Vampire Charger figure it out; when the light is green, the power’s clean.

The Vampire Charger was recently selected to move on to the final round of The Hackaday Prize, netting $1000 cash in the process. The next challenge (which will have another twenty finalists receiving $1000 each) is the Human-Computer Interface challenge. All you need to enter is an idea and some documentation, so dust off that project that’s been waiting for an opportunity, because here it is.

The Undead Remote

July 28, 2018 by Brian Benchoff 30 Comments

In the very late 1990s, something amazing was invented. White LEDs. These magical pieces of semiconductors first became commercially available in 1996, and by the early 2000s, you could buy a single 5mm white LED for less than a dollar in quantity one. A year or two later, an astonishing product showed up on infomercials airing on basic cable at 2 a.m. It was a flashlight that never needed batteries. With a small white LED, a few coils wrapped around a tube, and a magnet, you could just shake this flashlight to charge it. It’s just what you needed for when the Y2K virus killed all electronics.

Of course, no one uses these flashlights now because they suck. The early white LEDs never put out enough light, and charging a flashlight by shaking it every twenty seconds is annoying. There is another technology that desperately needs a battery-less solution, though: remote controls. They hardly use any power at all. That’s exactly what [oneohm] did for his Hackaday Prize entry. He created the Undead Remote.

The dream of a battery-less remote control has been dead since your parents got rid of that old Zenith Space Command, but here it is. This is really just a shake flashlight, a diode rectifier, a large capacitor, and some glue. Shake the remote, and you can change the channel. Is it useful? Certainly. Does it look weird and is it slightly inconvenient? Also yes. But there you go. If you want an easy way to deal with batteries in your remote control, this is a solution.

Micro-Organisms Give Up The Volts In This Biological Battery

July 27, 2018 by Donald Papp 18 Comments

Battery cells work by chemical reactions, and the fascinating Hybrid Microbial Fuel Cell design by [Josh Starnes] is no different. True, batteries don’t normally contain life, but the process coughs up useful electrons all the same; 1.7 V per cell in [Josh]’s design, to be precise. His proof of concept consists of eight cells in parallel, enough to give his cell phone a charge via a DC-DC boost converter. He says it’s not known how long this can be expected to last before the voltage drops to an unusable level, but it works!

Eight-cell, 3D printed proof of concept.

There are two complementary sides to each cell in [Josh]’s design. On the cathode side are phytoplankton; green micro algae that absorb carbon dioxide and sunlight. On the anode side are bacteria that break organic material (like food waste) into nitrates, and expel carbon dioxide. Version 2 of the design will incorporate a semi-permeable membrane between the cells that would allow oxygen and carbon dioxide to be exchanged while keeping the populations of micro-organisms separate; this would make the biological processes more complementary.

A battery consisting of 24 cells and a plumbing system to cycle and care for the algae and bacteria is the ultimate goal, and we hope [Josh] can get closer to that now that his project won a $1000 cash prize as one of the twenty finalists in the Power Harvesting Challenge portion of the Hackaday Prize. (Next up is the Human Computer Interface Challenge, just so you know.)

Bringing Augmented Reality To The Workbench

July 26, 2018 by Donald Papp 12 Comments

[Ted Yapo] has big ideas for using Augmented Reality as a tool to enhance an electronics workbench. His concept uses a camera and projector system working together to detect objects on a workbench, and project information onto and around them. [Ted] envisions virtual displays from DMMs, oscilloscopes, logic analyzers, and other instruments projected onto a convenient place on the actual work area, removing the need to glance back and forth between tools and the instrument display. That’s only the beginning, however. A good camera and projector system could read barcodes on component bags to track inventory, guide manual PCB assembly by projecting which components go where, display reference data, and more.

An open-sourced, accessible machine vision system working in tandem with a projector would open a lot of doors. Fortunately [Ted] has prior experience in this area, having previously written the computer vision code for room-scale dynamic projection environments. That’s solid experience that he can apply to designing a workbench-scale system as his entry for The Hackaday Prize.

An Integrated Electromagnetic Lifting Module For Robots

July 25, 2018 by Donald Papp 7 Comments

The usual way a robot moves an object is by grabbing it with a gripper or using suction, but [Mile] believes that electromagnets offer a lot of advantages that are worth exploring, and has designed the ELM (Electromagnetic Lifting Module) in order to make experimenting with electromagnetic effectors more accessible. The ELM is much more than just a breakout board for an electromagnet; [Mile] has put a lot of work into making a module that is easy to interface with and use. ELM integrates a proximity sensor, power management, and LED lighting as well as 3D models for vertical or horizontal mounting. Early tests show that 220 mW are required to lift a 1 kg load, but it may be possible to manage power more efficiently by dynamically adjusting drive voltage depending on the actual load.

[Mile]’s focus on creating an easy to use, integrated solution that can be implemented easily by others is wonderful to see, and makes the ELM a great entry for The Hackaday Prize.

Build A Wi-Fi Smart Scale

July 23, 2018 by Kristina Panos 10 Comments

There are plenty of ways to monitor changes in your weight. You can get a vague idea from the fit of your pants or the notch on your belt. But anyone who’s serious about getting or staying in shape must step on the scale to get the cold, hard truth in pounds or kilograms.

Instead of just buying one, [igorfonseca83] decided to burn a few calories and build his own smart scale that uses IFTTT to send weight data to his fitness tracker. It’s made from four 50kg load cells that are sandwiched between two pieces of plywood. An HX711 sensor module reads the load cells, and a FireBeetle ESP8266 uploads the data to Adafruit IO. His weight is simultaneously displayed on a FireBeetle LED matrix.

We applaud [igorfonseca83]’s efforts to make this an easy, educational project that anyone can replicate. The instructions are great, the pictures are clear, and there’s even a CAD animation of all the pieces coming together. Jog past the break to see the build video, and weigh in down below.

Continue reading “Build A Wi-Fi Smart Scale” →

A Caterpillar Drive That Actually Looks Like A Caterpillar

July 21, 2018 by Brian Benchoff 39 Comments

[Tom Clancy]’s The Hunt For Red October is a riveting tale of a high-level Soviet defector, a cunning young intelligence analyst, a chase across the North Atlantic, and a new submarine powered by a secret stealth ‘caterpillar’ drive. Of course there weren’t a whole lot of technical details in the book, but the basic idea of this propulsion system was a magnetohydrodynamic drive. Put salt water in a tube, wrap a coil of wire around the tube, run some current through the wire, and the water spits out the back. Yes, this is a real propulsion system, and there was a prototype ferry in Japan that used the technology, but really the whole idea of a caterpillar drive is just a weird footnote in the history of propulsion.

This project for the Hackaday Prize is probably the closest we’re going to see to a caterpillar drive, and it can do it on a small remote-controlled boat. Instead of forcing water out of the back of a tube with the help of magic pixies, it’s doing it with a piston. It’s a drive for a solar boat race, and if you look at the cutaway view, it does, indeed, look like a caterpillar.

Instead of pushing water through a tube by pushing water through a magnetic field, this drive system is something like a linear motor, moving a piston back and forth. The piston contains a valve, and when the piston moves one way, it sucks water in. When the piston moves in the opposite direction, it pushes water out.

The goal of this project is to compete against other solar powered remote-controlled boats. Of course, most of the other boats are using a DC motor and a propeller. This is a weird one, though, and we’re very interested in seeing how the production version will work.