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Tutorial: How to Make LED Cubes
The warm ambient glow of the LED Cube’s fantastic display of illuminated animation and hours of programming. They’re actually easier to create than you may think. We’ll show you how in plain English using simple designs and multiplexing
What is it about the combination of color and light which makes us automatically drawn to it ? Quite appropriately the video demo of Alex Beim’s LED bottle wall project is without sound. It’s all visual illumination as we watch 253 bottles light up with computer controlled LED bulbs . The glass bottles (probably Bacardi) are arranged in a grid of 23×11 on a flat mobile wall. Each bottle has a LED behind it.
RGB Computer Controlled LED Bottle Wall
Driving an LED with or without a resistor
In this post I will try to show, why it’s a good idea to use a current limiting resistor for an LED. And when it’s save to drive the LED without any resistor. If you read about LEDs, you will notice that everyone tells you, that you need a current limiting resistor.
In this project, you will make a flashlight that works without batteries. Even more amazing, you can recharge it in three minutes and it will run for more than 24 hours. Because the ultra capacitors can be recharged thousands of times, you may save the environment from ever receiving an old flashlight in the trash system.
Flashlight Without Batteries--from the book, "Haywired"
Programmable LED
An LED is used as output. As input I used an LDR, a light dependent resistor. This LDR changes its resistor as it receives more or less light. The resistor is then used as analog input to the microprocessors ADC (analog digital converter). The controller has two modes of operation, one for recording a sequence, the other for playing back the recorded sequence. Once the controller notices two changes of brightness within half of a second, (dark, bright, dark or the other way round), it switches to recording mode.
Solar Powered Temperature Sensing LEDs - HacknMod.com - Amazingl
What They Are and How They Work The Glowies use a small microcontroller , but they are really quite simple in both parts and function. The core of the unit is a silicon diode used as a temperature sensor (actually, two of them). These Glowies sense when temperature drops, and it turns blue. If the temperature rises, it turns red. Plus, it’s completely solar powered, so you never have to change the battery. And I used very inexpensive parts, so you can’t get much cheaper!