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Robots... ya can't live with` em...

Nathan Brown

nathan@expenseexpress.com

For a lot of people, myself included, building robots is not just a hobby it's an obsession. In fact there are days where robots consume every hour of the day, awake and asleep. What, pray tell, would drive likewise normal people, to this extreme passion? Well, it's quite simple really. Making. We are driven towards utter exhaustion to build a relatively small contraption that, after weeks of building and rebuilding, manages to guide itself around the room following walls. If you still don't know what I am talking about, let me share a personal experience that your IR range finder might be able to pick-up better.

Some time ago I built a small autonomous heat seeker. The goal was to make something that could play tag at a reasonably fast pace. I designed it to be a ball shaped bot that could rotate it's two hemispheres to roll in any direction. I named the thing, half for physical appearance, and half for a behavior bug that I could never figure out, thus I called it "Split Personality" or just Split. For all those veteran robot builders out there you can insert the name of your favorite robot instead.

Split was plagued from the beginning. I had more trouble getting the stepper motor drivers to work than any other IC I have ever worked with. But I finally got the thing built and running some what by itself. It was actually nice to look at. I cut a Nerf soccer ball in half, then carved out enough foam to stick Splits guts in. It fit nicely and with a good paint job, almost looked like a commercial product. So far I am about six months into the project and it still insists on repeatedly ramming itself into the wall. After eight months, on a whim I replaced the pyroelectric sensors and it actually started to work properly, for a while. This is when the motor driver relays burned out. It would have been nice, however, to know that it was just a cheep fifty cent relay before I replace every other part on the main board.

So now at one year, I had a fully operational autonomous robot that would chase me around the room. I stood back and watched it run around and look for something to attack. I was proud parent. Then a friend came over and asked about this strange black ball in the corner.  I turned Split on and let it run about a bit. My friend stood there, looked at Split, looked at me, then back at Split. Then resting his eyes on mine he asked, "How long did it take you to build that?". Bashfully I said it took six months, half the actual time. There was a dramatic pause, then he bust out laughing. I was very tempted to reach for my baseball bat and beat my long time friend to a bloody pulp. But I stood there enduring the agony of complete defeat. Now if my transistors weren't already heating up, little Split had to go and add injury to insult. He decided that since neither one of us were worth his time, so he decided to try the open door.

I am not sure why it took me so long to peruse my beloved bot, but perhaps it was my anger or maybe my heart was screaming "Run Split...Run Away!" Regardless of the reason, Split managed to get himself down three flights of outdoor apartment stairs, proving once more that the world should be made of Nerf. We raced after the tiny tyke and found him plunging through a puddle that was twice as deep as he was tall, again Nerf to the rescue. But there is only so much it could take, and we just couldn't get down the steps fast enough. We watched from the last flight as, we guess, his battery shorted out and he came to rest...in the middle of the street. I am sure you know what is coming, the last thing that old Split ever saw was the heat from the engine of the S-10 that hit him at thirty five miles per hour. That night I actually shed a couple tears for my dear Split. I can just see my little guy up in robot heaven right now, chasing after that truck all day long...

I still mourn for Split, but I keep going. It's just part of the obsession and a fact of life, or artificial life that is. I have heard women say that men will never understand what it feels like to give life, but I've seen fully-grown men talk all cutesy urging their little bot to run a maze. I haven't met a robot builder to date that I didn't think was a little weird, myself included. I conclude that it must be the torture of building things that never seem to live up to the expectations of the real world. Outsiders never seem to be able to grasp the complexity of building robots. A friend once told me, "When you build a Data [from Star Trek], let me know." Implying that anything else was just not good enough. It is a selfless activity and I applaud all robot makers big and small.

To all the makers and the ones we have loved and lost.