Wednesday, May 25, 2011

Heading out

So after running the car flat out and watching my children crash it into trees an parked cars, I decided it was far past time to get to work. I wanted to first address problems with steering from last year. I had a GPS module to tell me when to turn but I was using a rather crude delay to time the corning for the truck.

This year I got a compass! With the compass I should be able to get a heading to point the truck in the right direction. In the past I attempted to use the GPS modulehttp://www.blogger.com/img/blank.gif for this but had limited success. GPS modules need time to get locks and can take even more time it seems to establish that you are traveling in a specific direction. During last year's Autonomous Vehicle Competition at SparkFun I overheard several other teams having difficulty getting reliable data from GPS - either because of the weather (snow/rain) or because of weather proofing (plastic wrap, zip sandwich bags, tupperware, etc)

Instead I give you the HMC6352 for an instant heading. I wired up the HMC6352 to a development shield on my arduino and with some example code I was able to get reasonable values for where I pointed the little bugger. When I turned right the heading followed - turned left and numbers seemed to go in the right direction.

Yay!

Friday, May 13, 2011

Autonomous Vehicle Competition 2012

This year I competed again in the Spark Fun Autonomous vehicle competition. Like others in past years the weather was variable. Snow in the morning broke to sunnier skies by afternoon. A good time was had by all and it was great to see the field of competitors had grown a bit.

My 'bot Dr Zaius' Magnificent Flaming Banana opted for costumes instead of pyrotechnics. It seems there is at least one good spring fire that gives me pause. I was invigorated after seeing my cheap clearance RC truck attempt to make the first turn - straight into the loading dock / dumpster. Other heats were a little disappointing because of a short in my battery connector.

So after winning "best dressed" in my gorilla outfit, I decided that I might try a little harder this year and start earlier. In that vein I have also asserted to myself that I will no longer "rig up" things in a manner that "might work". Instead I will seek to construct things so as "not to fail". And I vowed to obtain a platform worthy of my code.

Enter the Traxxas Slash!

I picked up this little treat at the local hobby supply store. Attracted first to the claims that it can top out at something like 30 MPH and then completely sold when I saw how easy it would be to remove the cover and hack the steering servo and speed control unit.

I think we are in a much better starting position than we were last year but only time will tell!