So, I built my first ladybugbot last night. It costs me about $5 US to build one–~$.50 each for the motors, $1 each for the toothbrushes, $1 for the plastic/makerbot time, and the electronics are ‘free’, since I’m cannibalizing them, but I happen to know their factory cost is $.75. It takes me about 15 minutes to solder and hot glue each one.
For a cute little robot that can scoot around my floor, this is pretty good. Right now, though, it’s nothing more than a cute, R/C toy. I’d like to do something more.
First of all, it bugged me that I had to do 15 minutes of assembly per bot, and that I had to print out a top and a bottom, a la last night’s design, http://www.thingiverse.com/thing:12975. So, I made a single piece design that would print in 45 minutes, and should only take 5 minutes to assemble. Here’s my v3 design on thingiverse: http://www.thingiverse.com/thing:13004
So I started thinking about what a bunch of cute, cheap bots could do, and what I could put together in a day of soldering. I knew that I could get CDS cells in Sham Shui Po, here in hong kong, so I thought I could make some ‘bots with like seeking/fearing behavior. Wouldn’t it be cool to have a little swarm of bots that freak out and hide under the furniture when you turn on the light? Or a solar powered bot that seeks out light? This isn’t anything that BEAM roboticists haven’t done a million times before, but hey–everyone should have their own swarm, right? In the future (I’m designing the board now), I can put a small AVR on board so I can start programming more interesting behavior.
So today, I fired up the makerbot and started cranking out the next iteration of bots. For the first time, I tried the gcode copy-and-paste trick to make a bunch of objects in series using the automated build platform. It was pretty good–I got 5/6 shells and one ugly plastic blob. By the end of the afternoon, I had eight shells–my goal was 10 $5 ‘bots in the swarm, and I was feeling pretty good.
I started thinking a bit more about a simple little light chasing circuit, so I made this one with a dual comparator, some CDS cells, and two NFETS to drive the motors. There’s nothing novel here–this is right out of what the frog’s eye tells the frog’s brain, but it’s fast and cheap, and that’s all I care about. Video of the build coming tomorrow.