A Simple DIY Solar Tracker

June 17, 2011 by Jeremy Cook 40 Comments

The sun is a great source of energy, however, efficiently collecting this energy can be hard to do. One thing that can improve the results of solar use is to actually track the sun’s movement. [fanman1981] hooked up his own homebrew solar tracker using some pretty clever techniques.

For this hack he used two Harbor freight 45 Watt solar kits, some struts on the bottom, and a Dish Network satellite dish bracket hooked up to an “old school” antenna motor. Although one might think this device tracks the sun using some sort of sensor, it’s actually just a matter of hooking up the device to rotate at timed interval with a remote control. This interval is figured out with the benefit of some charts on livingonsolar.com.

To see it in use, check out the video after the break. He gives a good explanation about how everything was put together, but if you just want to see it move, fast forward to around 5:26, really quite impressive.

Continue reading “A Simple DIY Solar Tracker” →

EReader Battery Never Goes Flat (in The Sun)

June 15, 2011 by Mike Nathan 22 Comments

solar_powered_kobo

Instructables user [flapke] has a Kobo eReader and wanted to add some solar cells to it in order to charge the battery for free. The modification is similar to others we have seen recently, though his work was done so well that it almost looks stock.

He started out by sourcing a pair of solar panels from DealExtreme that purported to supply 5.5v @ 80mA. Like most of us are inclined to do, he tested them before use and found that they actually put out around 50mA instead. While the performance was a bit off, they still fit his needs pretty well, as the charge current needed to be at or less than 100mA to avoid damaging the battery.

He opened the Kobo’s case, and carefully removed a section of the back panel to make room for the solar panels. Once they were soldered together in parallel, he wired them to the eReader’s battery through a Schottky diode to prevent the battery from draining.

While we think his solar modification is a great way to ensure that he never runs out of juice while reading by the pool, we would certainly add a bit of extra charge circuitry to ours to prevent damage to the battery. What do you think?

Bikinis Of The Future!

June 14, 2011 by Mike Nathan 14 Comments

bikini_duo

It’s always interesting to see what happens when hacking meets clothing – check out this pair of bikinis, for instance.

This first item, called the N12 bikini (mildly NSFW), comes from Continuum Fashion and is composed entirely from Nylon 12, hence the name. Shapeways uses 3D Selective Laser Sintering (SLS) to create the tiny circles that make up this piece of swimwear. The suit is held together by tiny stretchy strings made of the same nylon, and the bikini can be printed to order. It seems like an interesting idea, but we wonder how it would hold up against some big waves or a game of beach volleyball.

The second item is a bit more functional. Designer [Andrew Schneider] has put together a bikini that can solve all of your energy needs while sitting by the pool. His solar bikini is covered with hand-sewn flexible solar cells that work together to produce up to 5v, available via a USB connection. He claims that you are free to go swimming in the suit, so long as you dry out the USB port before using it again. For all the guys out there crying foul, don’t worry – he’s got a suit for you too. He’ll be putting together a men’s suit in the near future that powers a 1.5 amp Peltier cooler to keep your beer cold – we just don’t want to know where the hot side of the Peltier goes…

Music Tank Puts The Boom In Boombox

May 27, 2011 by Mike Nathan 7 Comments

music_tank

When you think of Memorial Day weekend, what comes to mind? Well around here, all we can think about is this tank cum boombox that Instructable user [Elian_gonzalez] put together.

This build is actually the third version of his Music Tank, and it comes with all sorts of improvements over previous models. The tank is primarily constructed out of plywood, with cavernous compartments for holding all of its goodies. In its capacious body, the tank sports a 60 Watt stereo system that powers a pair of external speakers mounted on either side of the turret. The turret itself contains an air-powered cannon built from PVC tubing, which we imagine can be used to shoot a multitude of different projectiles.

While the concept itself is pretty cool, the tank happens to be nearly self-sustaining as well. The tank has a pretty deep battery well and uses a 50w home made solar panel to help keep things topped off while in use. [Elian] does not specify a total running time, but we imagine that it can go for hours on a nice, sunny day.

Keep reading to see a long video walkthrough of the Music Tank MK3 in action. Continue reading “Music Tank Puts The Boom In Boombox” →

Dimming Control For An Ikea Solar Desk Lamp

May 16, 2011 by Mike Szczys 15 Comments

[Frank] decided to augment his desk lamp’s features by adding dimming controls (translated). Since the light source is a triad of LEDs the best method of dimming their intensity is to use Pulse Width Modulation. That’s the method that he went with, and luckily the SUNNAN lamp from Ikea which he’s using as the donor for the project has just enough room to squeeze in the parts necessary for this hack.

You need two main bits to use PWM with a lamp like this; a microcontroller (or possibly a timer chip like the 555) and a transistor to protect that chip from the current necessary to run the LEDs at full brightness. [Frank] went with an ATtiny13 and a 2N2222 transistor, both quite common and very inexpensive (you can even pull the microcontroller from a light bulb if you know where to look). Two buttons were added to the top of the lamp base which allow for up and down controls. There’s even an SOS function which is triggered by pressing both buttons at the same time. [Frank’s] happy to show off the completed project in the clip after the break.

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Scout, The Autonomous Transatlantic Boat

May 2, 2011 by Mike Nathan 22 Comments

autonomous_boat

Sailing a small boat across the Atlantic ocean is quite the daunting task. As many have discovered, it is a journey often fraught with perils, typically ending in failure. A team of four college students decided the best way to get a small boat across the ocean would be to remove the human element from the process, so they set off to build an autonomous craft to take on the task.

Like most projects, this one started as a handful of wild ideas exchanged between friends [Dylan Rodriguez and Max Kramers]. As they thought about it more, they decided that turning [Max’s] sailboat into an autonomous ocean-going craft would be pretty awesome, so they got to work. Recruiting help from their friends [Brendan Prior and Ricky Lyman], the project started to quickly take shape, and Scout was born.

Scout is 8 feet long and consists of foam core covered in carbon fiber. It is filled with various electronic components such as a SPOT tracker, a battery bank that will power the boat for up to 25 hours, and the various servos and motors which will be used to pilot the craft.

It’s a rather ambitious project, though the boat is nearly complete – just in time for their launch, slated for May 29th. We’ll certainly be keeping an eye on this project as the launch date approaches – good luck guys!

Head on over to their Kickstarter page to see a promo video introducing Scout.

Continue reading “Scout, The Autonomous Transatlantic Boat” →

Auxiliary Battery Pack For Field Operations

April 18, 2011 by Mike Nathan 11 Comments

portable_battery_pack

Ham operator [Ken – wa4mnt] wrote us to share a small project that he uses nearly every time he goes out in the field. His portable sealed lead acid battery pack (PDF) always ensures that he has a 12v power source at his fingertips, both for fun as well as in emergency situations.

The battery pack is pretty simple, and includes a 12v, 17ah battery strapped into a light aluminum chassis which he fabricated. The battery is secured with zip ties, so it can easily be swapped out or replaced without much fuss. The frame also sports a tiltable 4w, 17.5v solar panel that keeps the battery topped off and ready to go at all times. He stuck a voltmeter to the top of the battery to keep an eye on things, and he employs a 10A fuse to make sure he doesn’t fry any sensitive radio components should something go wrong.

The battery pack is pretty compact when you think about it, and we imagine it would be great to have on hand for a wide array of outdoor activities. Even if you’re not into Ham field operations, it’s hard to argue with its usefulness during power outages.

[Ken] doesn’t appear to have any published plans for the chassis or the electronic portion of the pack, but we’re pretty sure he would share if asked.