Sure, it’s probably a gimmick to [Jon Masters], but we absolutely love the pedal-powered server he built using a group of ARM chips. [Jon] is an engineer at Red Hat and put together the project in order to show off the potential of the low-power ARM offerings.
The platform is a quad-core Calxeda EnergyCore ARM SoC. Each chip draws only 5 Watts at full load, with eight chips weighing in at just 40 Watts. The circuit to power the server started as a solar charger, which was easy to convert just by transitioning from panels to a generator that works just like a bicycle trainer (the rear wheel presses against a spin wheel which drives the generator shaft).
So, the bicycle generator powers the solar charger, which is connected to an inverter that feeds a UPS. After reading the article and watching the video after the break we’re a bit confused on the actual setup. We would think that the inverter would feed the charger but that doesn’t seem to be the case here. If you can provide some clarity on how the system is connected please feel free to do so in the comments.
Continue reading “Pedal-powered 32-core ARM Linux server”
[Eduard Ros] wrote in to show off the latest version of his Arduino powered autonomous rover (translated). You may remember seeing the first version of the build back in June. It started with a remote control truck body, adding an Arduino and some ultrasonic sensors for obstacle avoidance.
The two big wheels and the pair of sensors look familiar, but most of the other components are a different from that version. The biggest change is the transition from four wheels to just three. This let him drop the servo motor which controlled steering. At first glance we though this thing was going to pop some mad wheelies, but the direction of travel actually drags the third wheel being the larger two. The motors themselves are different, this time depending on gear-reduced DC motors. The motor H-bridge is the same, but [Eduard] used a simple transistor-based inverter to reduce the number of pins needed to activate it from two down to just one. He also moved from an Arduino Uno to a Nano to reduce the footprint of the controller.
[Chris] and [Dom] wanted to build their own battery backup system on the cheap. They were very creative in sourcing the parts, and ended up putting together a battery-backed CCTV system for about eighty bucks.
Since short power outages are fairly common in the area this battery backup makes sense. We’ve seen some pretty gnarly whole-house systems but this is more of a novelty. That’s a good thing, because the hacking duo decided to reuse batteries which were headed for the scrap yard. They’re connected to a trickle charger which makes sure that they’re continually topped off when mains power is energized. But when there’s a blackout a relay switches an outlet box over to the inverter (also a used part).
The system is outlined in the entertaining video after the break. You’ll see they guys show off the completed build, followed by a walk through of the circuit they designed and how it functions.
Continue reading “Roll your own battery backup system”
Want to shoot lighting bolts from your hands to punish your enemies? You can (almost) do just that with this static electricity generator hack. Above you can see the charge jumping off of this guy’s knuckle and surging through the LED. But that’s not the only trick you can pull off when wearing just a bit of hardware around your ankle. The video after the break shows sand grains jumping around as a charged hand is waved over them.
The trick is done by powering a negative ion generator from a 9V battery. This can’t be done directly, since the ion generator is looking for an AC power source. But conversion is as easy as scrapping an inverter which is designed to plug into a car cigarette lighter. Everything is shoehorned into a glasses case, which can then be strapped on to your ankle. Why this fascination with the ankle area? One part of the answer is that this provides an easy way to interface the ion generator output with your skin. The other part of the answer is that you need to make sure the system is grounded (but you’re not) and the build includes a ring that goes around your shoe to achieve this.
Check out the demo and full build instructions in the video after the break.
Continue reading “Ankle bracelet lets you become Emperor Palpatine”
[Photonicinduction] has an impressive battery backup installation that powers his whole house. Unlike a standalone emergency generator which would require you to hook up all of the device you want to run, this setup sits in between the power meter and the breaker box, ready to step in when needed.
But get this, he’s not just using it as a backup system. It kicks in during the day to run everything including two freezers, a refrigerator, his lights, television, and computers. That’s because the price per kilowatt-hour is quite a bit higher during the day than at night. So after 10:30pm the system patches his house back into the grid and charges the batteries for use the next day.
What you see here is just a portion of his system. The control board is not pictured but is very impressive, including a network of relays which are used as a fail-safe system so that there are no conflicts between mains and the battery system. Check out his 15-minute walk through of the system after the break. Continue reading “Whole house battery backup used for lower power bills”
[Fileark] had the backlight on his digital picture frame go out one day. These are generally Cold Cathode Fluorescent Lamps which require an inverter to source the voltage necessary for proper operation. When they stop working, the inverter is usually to blame. Since that circuit is made up of pretty small surface mount circuitry, he decided to replace the backlight with LEDs rather than repair the inverter.
In the video after the break [Fileark] will walk through the entire project. After snooping around inside the picture frame he sizes up a strip of LEDs on a flexible substrate. The metal retaining bracket that hosts the LCD must be altered to fit the new light source and for that, he’s included a hacking montage in his video. The final result looks stock and he estimates the screen is around 97% as bright as with the original backlight.
This isn’t the first time we’ve seen an LED edge-lit upgrade. The last one we saw even used a custom PCB to host the LEDs.
Continue reading “LCD: Replacing CCFL with LEDs”
[Electorials] actually makes working with a flyback inverter sound rather easy. This comes hot on the heals of the huge high voltage collection we saw the other day, but slows way down in the presentation of information. This makes the project very approachable for the newbie, especially considering that the majority of the testing is done with low voltages.
He’s using a flyback transform for this project, which can be pulled from an old CRT monitor. Once you have one in hand, all that’s required to figure out how to use it is a voltometer, a 9V battery, a MOSFET (also salvaged in this case), and miscellaneous components. Once he establishes what each external connection does electronically, [Electorials] builds his circuit on a breadboard, then uses it to create plasma in the bulb above as well as to light up a CCFL.