Dozer Photovore

Revised Edition

This is my own version of "Dozer", a light-seeking wheeled robot. Thanks to Darren Busson, who created and shared this wonderful circuit (originally a headbot circuit). And thanks to Jo Charles who also shared this robot to the BEAM group. Thanks guys!

This version that I made, consists of only few added circuits to make it more creative and entertaining. When this bot is placed in a dark area, it will just spin around like a top. And at the same time, a multi-colored LED flashes on top of it. But if a light has been detected, it will go towards it. Another behavior of this is that, it moves to the light or chases a light for a few seconds then pauses for a few seconds again, then the cycle repeats (go...stop...go...stop).

It also has a built-in low voltage indicator. A small red LED lights up when a low voltage is detected (at 3.3 volts - set trip point). The power source I've used for this bot is just a cellphone battery (3.7 volts at 850mA). When it hits an obstacle, it will just back up for 2 to 3 seconds then proceeds to go forward again. Simple isn't it?

My work for this bot is not that beautiful because, maybe I'm not in the mood when I did this or maybe I'm so lazy to make the "Aesthetics". But hey, this circuit kicks butt, right? I mean, this dozer bot is one of a kind and it's cute isn't it? It's also entertaining, and it's like you can't stop playing with it. Try it yourself and let us know your reactions. You'll see what I mean. Enjoy!

P.S. You can also use hobby servos or any geared motors for this bot. Goodluck BEAM builders!

P.S. This bot is supposed to be 1" x 1" in size. It's what I really planned it to do, in fact I did. Unfortunately, I can't find a smaller rechargeable batteries for it, instead...I bought 3 button cells (4.5 volts total) and it ran my bot nicely, but the problem was, it easily drained after a couple of minutes...it sucks too! That's why I've changed my mind and I ended up using a cellphone battery (as always), which made it a little bit larger in size.

Schematic Diagrams

Assorted versions