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.

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.

Open Source Laboratory Rocker Is Super Smooth

July 20, 2018 by Donald Papp 19 Comments

Lab equipment is often expensive, but budgets can be tight and not always up to getting small labs or researchers what they need. That’s why [akshay_d21] designed an Open Source Lab Rocker with a modular tray that uses commonly available hardware and 3D printed parts. The device generates precisely controlled, smooth motion to perform automated mild to moderately aggressive mixing of samples by tilting the attached tray in a see-saw motion. It can accommodate either a beaker or test tubes, but since the tray is modular, different trays can be designed to fit specific needs.

Source code and schematics are available from [akshay_d21]’s Google Drive and the 3D models are also available from the National Institute of Health’s 3D Print Exchange. A demonstration video is embedded below, in which you can see how smooth and controlled the motions are.

Continue reading “Open Source Laboratory Rocker Is Super Smooth” →

Energy Harvesting Design Doesn’t Need Sleep

July 19, 2018 by Donald Papp 10 Comments

Every scrap of power is precious when it comes to power harvesting, and working with such designs usually means getting cozy with a microcontroller’s low-power tricks and sleep modes. But in the case of the Ultra Low Power Energy Harvester design by [bobricius], the attached microcontroller doesn’t need to worry about managing power at all — as long as it can finish its job fast enough.

The idea is to use solar energy to fill a capacitor, then turn on the microcontroller and let it run normally until the power runs out. As a result, a microcontroller may only have a runtime in the range of dozens of microseconds, but that’s just fine if it’s enough time to, for example, read a sensor and transmit a packet. In early tests, [bobricius] was able to reliably transmit a 16-bit value wirelessly every 30 minutes using a small array of photodiodes as the power supply. That’s the other interesting thing; [bobricius] uses an array of BPW34 photodiodes to gather solar power. The datasheet describes them as silicon photodiodes, but they can be effectively used as tiny plastic-enclosed solar cells. They are readily available and can be arranged in a variety of configurations, while also being fairly durable.

Charging a capacitor then running a load for a short amount of time is one of the simplest ways to manage solar energy, and it requires no unusual components or fancy charge controllers. As long as the load doesn’t mind a short runtime, it can be an effective way to turn even indoor light into a figuratively free power source.

SPINES Design Makes For Modular Energy Harvesting

July 17, 2018 by Donald Papp 7 Comments

The SPINES (Self-Powered IoT Node for Environmental Sensing) Mote is a wireless IoT environmental sensor, but don’t let the neatly packed single PCB fool you into thinking it’s not hackable. [Macro Yau] specifically designed SPINES to be highly modular in order to make designing an energy harvesting sensor node an easier task. The way [Macro] sees it, there are two big hurdles to development: one is the energy harvesting itself, and the other is the software required to manage the use of every precious joule of that harvested energy.

[Macro] designed the single board SPINES Mote in a way that the energy harvesting portion can be used independently, and easily integrated into other designs. In addition, an Arduino library is being developed to make it easy for the power management to be done behind the scenes, allowing a developer to concentrate on the application itself. A solar-powered wireless sensor node is one thing, but helping people get their ideas up and running faster in the process is wonderful to see.