Gordon Koo

Stanford CS '08

LinkedIn 2010-2013

Airbnb 2013-

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  • Off My Arduino Training Wheels

    29 May 2012

    In May 2011, I went to my first Maker Faire. It was incredibly inspiring to see the culture of making things, shared by so many people of such diverse backgrounds. Inspired by a demonstration of the power of Arduino, I picked up a Getting Started with Arduino kit. I went home that night, opened up the kit, and poked around. I was able to get a red LED blinking before I decided to turn in for the night. The kit unfortunately went underneath my bed and there it stayed for one whole year.

    In May 2012, I realized that the next Maker Faire was coming up and I hadn't done anything other than turn on a red LED. I made it a point to go through the kit so that I could buy more things at the Maker Faire. While I only made my way through about 75% of the kit, I think I got the gist of it. I had learned how to crawl. I was ready to learn how to stand.

    I went to Maker Faire and it was just as inspiring as last year. Probably the best part was the Expo Hall, where you could just wander around and look at all the cool things that people have created. I ended up getting a soldering kit, the Ultimate Microcontroller Pack, and the O'Reilly Arduino Cookbook. This time, I didn't wait a year to try out my new toys. This past weekend, I made my way through quite a bit of the Arduino cookbook, learning how to use different sensors and how to send data input to the Arduino board through my computer. But I was still mostly turning LEDs on and off. I wanted to work on something substantial!

    I decided to try building an Arduino controlled robot/car/four-wheel-thing for my first project. I had and still have no idea what I'm doing, but each day brings me a little closer. I started off by buying a really cheap remote control car from Radio Shack. It cost me $8. Not too bad! I was amused when the man behind the counter at Radio Shack asked me if I wanted to buy a one-year warranty for the low price of 99 cents. Considering I would be ripping the car apart at home within 15 minutes after the purchase, I politely declined.

    I had a car. Now what? I unscrewed every screw I could find and pried everything open that I could pry. I got to the board that controlled the motor and the front wheels. On the advice of another website that had done a similar project, I clipped the wires and freed the board.

    I was also left with a nice set of wheels attached to a motor -- perfect for experimenting! I soldered two jumper wire cables to the wires that I had clipped so that I could plug them into my breadboard more easily.

    Now how should I experiment? All of the tutorials online seemed to require a ton of more materials than I had on hand, and there was nothing in the Arduino Cookbook about repurposing a remote control car. Or was there? It turns out that Arduino Cookbook did in fact have a section on controlling the speed of a brushed motor by using a transistor. Great! Now if I could only just get my Arduino to power the motor in this car and turn the wheels, not only would that be completely awesome, but it would also validate all of the effort that I went through over the past weekend. My setup was extremely hacky, but I was actually able to get it working! Here is what I've accomplished so far:

    Awesome! My next steps involve using an H-bridge to control the motor movement, and after that, controlling the servo that controls the front wheels.

    It's an incredible feeling to program something that actually exists in the real world for the first time, something whose existence does not consist entirely of pixels on a screen. I think Arduino will take a permanent place in my list of spare-time hobbies. I can't wait to build more things.