The bot is built on a sheet of yellow plastic that's fairly strong yet easy to cut with some grunty swipes of the utility knife. It uses a single power source connected directly to Vin on the arduino. The battery pack is mounted on the underbelly (6aa NiMH rechargeables). The arduino and mini breadboard are mounted on top. For locomotion, i have 2 gws continuous servos connected to the regulated 5v output of the arduino. I have a switch on the breadboard controlling the servos, so I can start and stop them independently to the arduino. For wheels, I use leftover CDs that i drilled holes in and mounted to the servo horns using wire. For a 3rd wheel, I used one of the slippery pad things intended to go on the bottom of chair legs to help it slide. With the batteries, it weighs 1lb, 2oz. It's programming is dead simple, I basically just turn on both wheels and roll. I did break out the wheel functions to a separate file (not a library, just crammed in a .h) to aid in reusing in my next bot. I think I have a power thing I don't understand with this one (alert:software geek doesn't know which end of a capacitor is up). I have loop() do a serial.print() each time it gets called, and that print stops happening when the wheels start. I'll be damned if i can can find meaningful data on the servos to tell me what their peak power draw is, so it perplexes me. It will perplex me less when my motor driver arduino shield arrives, because i think that will help. I also need to start driving the motors from a different power supply than the arduino. I'm imagining my next bot sagging under the weight of all these batteries.
It scoots around the kitchen floor, it is rather cute. I did learn a lot by building it. Here it is ready to roll:
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