Pictured left: The RS-550 motor

The single passenger F-150 that we’re using contains two RS-550 motors which, according to the datasheet, can draw 70A of current when stalled. Typical performance is around 9A, but is still much higher than I expected. I should note that I’m not quite sure precisely what I expected, but I’m a little concerned about creating a motor controller for something that drives so much current. I may take a serious look into purchasing a pre-fabricated motor driver.

It is also noteworthy that that RS-550 motor is actually capable of running on voltages as high as 14.4V constant. And while I have no immediate plans to upgrade the battery, it’s nice to know that we can unlock some serious potential for speed. I’m already fantasizing about hosting my own little autonomous NASCAR circuit on a quarter mile running track. But one thing at a time.

I had my brush with compromise the other day. It seems that while I presumed that our autonomous vehicle would run solely on the power of microcontrollers, my partner was under the impression that we would be using a PC as as the brains of the operation. And to make matters worse, he insisted that the PC run Windows.

I did my best to argue against the Windows PC, but in the end my friend proved to be doggedly relentless. Over time, I’ve actually grown to appreciate the unexpected change however; the beauty of compromise. Obviously a PC will provide us with a much more powerful platform on which to build.

In the end, we agreed to use a Dual Core 1.8GHz Dell laptop that has been lying around my apartment unused for over a year. This is proving to be an excellent experience on working in a group setting where the goals of the individual members of the group vary widely.

The article in the April 2008 issue of Servo Magazine titled “Turn a Kid’s Ride-on Car into a GPS Guided Robot” changed my mind. I had never considered using such a simple platform to build a (relatively) low cost autonomous vehicle. My interest was peaked.

As luck would have it, a close friend and colleague expressed interest in a similar project. We decided to undertake the project together. And as it turns out, I didn’t need more time to get ready. What I needed someone to share my interest with. Although my friend certainly brings a great deal of technical knowledge to the table, what I am most excited about is the opportunity to share in the experience with someone who can appreciate my enthusiasm.

I will be documenting our little experiment on this blog. It is my greatest hope that someone will read these entries when building their own autonomous vehicle and perhaps avoid some of the (many) mistakes that I am certain we will make along the way. If even one person can be spared the agony of watching their hard earned time and money go up in smoke, even at my own expense, then the time and effort spent writing this journal will have been well worth it.

Enjoy!