Let's Make Robots!

"zig-zag" microbot

avoiding obstacles using infrared.

This is my robot, made for the microbot challenge.

I did like to use of parts I already had lying around instead of buying new parts.


I did want to merge 2 9g servos into each other to make a small robot. so I did take them apart and removed the potentiometers. Then filed the hole bigger so the motor of the opponent side would fit in more deeply.

Also removed the notch using a knife.

Then this is the result: 2 servos together but only 1 servo width.

Then added the gears again except the last gear. and I did put on some lego wheels. however the potentiometer didn’t fit anymore I still needed the axle. therefore I hotglued a pinch pin in place. then I had to find a way to keep the gears from falling off.. and a simple piece of wire seems to be the most simple solution.



when I had everything working on breadboard I did solder the rest of the parts in place.

left on top the 16f628a microcontroller, in the center the 6v battery and the IR leds in shrinktube. right on front there is a capacitor and underneath there is the tsop1738 IR receiver.


I had some problems as it turns out the battery I use is too weak to power the 2 wheels at the same time. I tried to lower the speed but that didn't help. so now I turn them on left and right alternately.


and some measurements:

Edit: Added a picture with some batteries for size comperation:

After all I have to say is was both challenging and fun to build such a small robot. Maybe there will follow more little robots as there are fun to build. :D

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Great "little" build Dannyv! It's hard to get the size until I actually look at my own ruler. Very nice.

Personally I like how he "walks" instead of rolls. Nice work around of a limitation you ran up against.

It gives the little thing more personality I think. I'll have to try that with one of my bots sometime.

Again great build and good luck with the challenge!


Love your bot! The servo teardown and rebuild is a novel solution, exactly the kind of thing I was hoping to see in this challenge. Nice solution, it's very tiny. Nice work!

Well done. I like how you combined the servos.

Well done Danny that's something what we not have often here :-) Not only the brain is something exotic but also your solution to shrink the total size by modifying the servos. 

About the battery, why you don't try small LiPo batteries, they would be powerful enough by keeping the weight in a acceptable limit.

I like your solution to powering the motors with the small batteries.  Great idea!  Nice robot.  Looks really cool.

I have doubt about putting 2 batteries on him so he would be able to drive straight forwards and a lot smoother, but That would make him a lot bigger and to seperate the power I would have to desolder almost everything and have to chance too much, seen the challenge almost ends already. And 2 batteries in parallel didn't the trick.

Damned nifty, sir! The popping open the 9gs and still using their housing got me. I'd never thought of it.

Thank you!