DIY Solar Panels

September 8, 2009 by James Munns 74 Comments

solar

Reader [unangst] pointed out to us an article in the U.K.’s Daily Mail, where a teenager from Nepal had managed to create a 9v, 18W solar panel using human hair rather than the usual semiconductors (usually crystalline-silicon). The complex silicon in solar panels are what keep the prices out of reach of developing nations, and while there are a number of new technologies that are helping bring down the cost, [Karki] managed to make his solar panel for only £23 (roughly $38). He also claims that when mass produced the price could drop substantially down to under $10 a panel, which would shatter the $1/watt sweet spot.

The melanin in hair acts as an organic-semiconductor, and while the hair does not have the longevity that silicon panels have (months rather than years), these panels can be made cheaply and serviced with little to no complex knowledge. Using melanin as an organic semiconductor seems to be a newer idea, because information seems hard to come by, but we managed to find a research paper from 2007 that explored the energy absorption attributes of melanin, as well as some good background info for the science types.

Research Paper (Warning: PDF)

So, Hack a Day readers, which one of you is going to make your home-brew solar panels first? Let us know when you do.

Thanks [unangst].

[digg=http://digg.com/environment/Teenager_Makes_DIY_Solar_Panels_from_Hair_Hack_a_Day]

Arduino Crib Rocker

September 8, 2009 by Caleb Kraft 16 Comments

DSC00102_rocker01 (Custom)

Anyone with children will understand the value of this project immediately. This is an Arduino controlled sound activated crib rocker. [Lars] built a custom suspension system for his baby’s crib which allows a servo, mounted to the floor to rock it gently back and forth. Ok, maybe it’s a vigorous rocking, but that’s what some kids want. At least he’s safe and moderately immobile. He had to make a custom amplifier circuit to get his microphone working with the Arduino. It seems to all work perfectly now, triggering to begin rocking when it detects the baby’s cries. This should buy them a few extra minutes of sleep until the baby is truly hungry or annoyed. You can see a video of it in action and download the Arduino code on the project page.

[via littlebridceo]

Cellphone-controlled Home

September 6, 2009 by Jake W 9 Comments

[youtube=http://www.youtube.com/v/exTpD0–BCo]
[Tixlegeek] used a Motorola 68HC705J1 development board to remotely control his home through his cellphone. The video above, as well as [Tixlegeek]’s website, is in French, though the video has been captioned. The development board (called the ERMES125) is controlled by a PIC externally. It has an array of LEDs, and apperantly a few high voltage relays. The PIC is connected to a laptop through a serial interface. The laptop is running a small web server, which uses CGI to control the PIC from a webpage. This system allows [Tixlegeek] to log onto the webpage from his web enabled phone, click a few buttons, and have appliances turn on or off through relays controlled by the PIC (via serial signals from the laptop).

Variable Range Sprinkler

September 4, 2009 by Devlin Thyne 14 Comments

[vimeo http://vimeo.com/6409575 w=470&h=352]
[Pete], a musician, and the guy behind SparkFun’s pogobeds and locking footprints has a sprinkler hack. He wanted to keep his dog, Choppy, happy with a green lawn while also keeping his sidewalk water free. To solve this problem, he hacked his sprinkler and hose to adjust the sprinkler’s range. He uses an Arduino to read a potentiometer signifying the direction that the sprinkler is facing and a servo to adjust a hose valve that controls the sprinkler’s water flow. Be sure to check out the video above to see it in action.

Single Tube Nixie Clock

September 3, 2009 by Caleb Kraft 20 Comments

[youtube=http://www.youtube.com/watch?v=a-7QAWshEXo]

This single tube nixie clock cought our eye today. After receiving an IN-8 tube from a friend, [Trax] wanted to find some project to show it off. He decided on an art piece that doubles as a clock. Tastefully mounted in a simple wooden box with a pretty inlay, the tube is lit from below with a green LED that pulses every second. A single button, located on the back, out of view is pressed to request the time. You can see the time being displayed on the video above. To see the guts and read about how he’s using the PIC16F84’s built in clock to keep track of time, check out his site. Even though this is a Nixie, it reminds us of the Decatron kitchen timer we saw recently.

[via Hacked Gadgets]

Simple Automatic LED Lamps

September 2, 2009 by Mike Szczys 12 Comments

simple_led_lamps

[woody1189] put together some automatic lighting for his closet. Nine LEDs are grouped into three lamps and controlled by a hall effect sensor. He prototyped this on an Arduino and then migrated over to an ATtiny85. Although the current implementation could be accomplished without a microcontroller, we’d love to see some firmware improvements such as an auto shutoff for when you forget to close the closet door. The hall effect sensor seems to pop up in a lot of projects so make sure you get a few of them with your next parts order. Video of this in action after the break.

Continue reading “Simple Automatic LED Lamps” →

Twitter Remote Control

September 2, 2009 by Jake W 16 Comments

We’ve already brought you a homemade Twitter-enabled washing machine, and toilet, but now a new innovation is being brought to the table by a bigger player. IBM is working on a tweeting television remote, which would allow the user to inform the world what they are watching. Although unfiltered reporting could create awkward situations, the combination of America’s love for television and Twitter is sure to yield interesting results. They also mentioned that it could be configured to report to other sites, such as Facebook or joost. Any ideas why IBM would have in such a patent are welcome in the comments. More info can be found here and here.