I’m really happy with the BBB freeduino I’m using for this project. But I think next time I’ll just make a custom ‘Roboduino’ pcb.

Here is a schematic if you’re interested.

This is the motor driver wiring.

The light sensor uses a photocell and a 330 Ohm resistor.

Here is the actual winch that will pull the cable that lifts the door. Its built from a cd-rom drive, legos, and plywood.

A week ago I was asking “k, wtf is an ohm?” Now I know it’s just stupid maths. This is the formula for calculating resistance(Ω), voltage(V) and current measured in amps(I).

• V=(I*Ω)
• I=(V/Ω)
• Ω=(V/I)

So an example of figuring out voltage lost through resistance would be like so: Say you have a wire that has a resistance of .6Ω resistance and you need to run 12 amps through it. Due to the resistance you’re going to lose some voltage.  So what we know is Ω=.6 and I(amps)=12 so your equation will need to be V=(12*0.6) which happens to be 7.2 V.

What would the implications of this be? Serious, if you’re using a 9v battery you’re going to be cut down to 1.8v. That is why car battery wires are really thick, to lessen resistance.

Another example of Ohms law would be an LED with a proper power supply. If your LED reccomends you use 3v at 12mA and you have a 9v battery, which resistor should you pic? V in this equation stands for the difference in voltage between the battery and the LED. So you take 9-3=6. We’ll need to trim 6V. And the amperage we’re looking for is 12 miliMmps or .12 amps. So the math would look like this:

• Ω=V/I or Ω=6/.12 or 50Ω

The resistor you’ll need is a 50Ω to properly light this made up 3v 12mA LED with a 9v battery.

Anyway, this is more for me than anyone. Enjoy.

This instructable will show you a way that works, and a way that really works to drive DC motors.

http://www.instructables.com/id/Control-your-motors-with-L293D-and-Arduino/?ALLSTEPS

If you’re still wondering why one way works better than the other I highly suggest you read this article on power regulation and pick up the caps and diodes.

// Troy Watson Arduino Powered Chicken Coop Door
// Waits for the sun to come up, turns a servo to open a drawbridge then waits and closes the bridge.

#include <Servo.h>

Servo servo0;  // create servo object

int sensVal = 0;  // analog pin used for light sensor
int rotateDeg = 1080;    // number of degrees to lower drawbrigde
int darkVal = 55;

void servoUp()
{
servo0.write(rotateDeg); //tells the servo to turn out the winch
}

void servoDown()
{
servo0.write(-1*rotateDeg);  //writes the servo to turn back up?
}

void setup()
{
servo0.attach(9);  // attaches the servo on pin 9 to the servo object
}

void loop()
{
if (sensVal > darkVal){                      // duh
delay(360000);                         // waits 6 minutes
if (sensVal > darkVal){                // checks the sensor again to make sure its really the sun not just some retard in the neighbors driveway
servoDown();                     // lets door fall open gracefully
delay(43200000);                 // waits 12 hours.
servoUp();                       // pulls door back up
}
}

}Download it here.

I got a free sample of CyberClean® at CES on saturday and must say its pretty cool stuff. It’s somewhere between lysol and flubber but definitely cleans the gunk out of the dark, nasty orifices of your gadgets.  The guy demoing the stuff grabs my iPhone and rams it in the back hatch with this ball of yellow gel while chanting his mantra “Just press and pull, as easy as that. Removes dust and dirt, not only dust and dirt, but also germs, kills germs on contact. Just push and pull, don’t rub.”

I was skeptical of the claims of germ killing power until I looked up a few of its ingredients on wikipedia:

• Diazolidinyl Urea – Antimicrobial
• Boric Acid – Insecticide (huh) I think this might just be used to setup the glycerin to form the gel
• Methylparaben & Propylparaben – Anti-Fungals

I’m impressed. This stuff really works. Just as advertised it pulled all the dirt, dust and hair out of the bottom port of my iphone with ease. It sure beats a q-tip and scrubbing. And it’s fun to play with.

My wife got me the advanced arduino starter kit for Flying Spaghetti Monster-mas! I’ve been having a ton of fun playing with this thing and trying to remember how to program . My office is full of blinking LED’s and beeping speakers and swearwords. This thing is great! I can’t wait to buy a dedicated arduino for my chicken coop door opener. haha

What I’ve done so far:

• blink an LED
• fade and LED
• botton controlled fading LED
• light sensing box that sounds an alarm when opened.

I give you: vulcan.troseph.com. The latest addition to my computer collection. She’s no spring chicken but she’s going to have a lot of web hosting power.

Specs:

2x Dual core 2.8Ghz Xeon Procs

4Gb ram

750GB raid 10

Ubuntu 8.04 LAMP stack

It should be up and running within a couple weeks. Wewt!

The circuit is pretty simple. And stolen from here.

I used identical components aside from the LED’s.

4.7k Resistor
2k-100k LDR
2N3904 Transistor
Guts salvaged from the CD drive of a Sony boom box
4AA battery holder
mercury switch

I have been informed that you had overtime on this up coming paycheck. Payroll spoke with Dick VanLame about it and they are not coming down hard on anybody this time, but please don’t do it in the future, or it warrants an occurrence in the future.

John Doe has 0.05 Overtime hours for the 2009.11.16 to 2009.11.30 pay period.

Obsequiously,

Manager Testes,
Swing Shift Supervisor
<mtestes@awfulhost.com>

0.05 = 3 minutes! This place is a joke!

Advanced Arduino Starter Kit

Acer EEE PC 1101

Ruger Mark III