Let's Make Robots!


Follows light


Problem solved:

Okay so my problem was that motors didn't get enough power. I tested this with 6v and it worked.


Okay,so here's my third BEAM-robot.
But it just don't want to work!
I got one picture from very close:

Parts i used:

- some wires
- two 2N3904
- two LDRs
- two DC motors
- AA battery holder 

But if you know where i have to connect those wires, or what is the problem, tell me please!
I add video when this is fixed.
I tested all parts and they work,even transistors!
So wiring is the problem? 

Schematics: (hope you understand these)

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Ah.. ok. I didnt see the shoutbox until now. Botfin should change this indeed.

@ Botfin:I do not want to complicate things, if so then ignore this following:

Maybe handy to know that a diode (also the one inside a transistor) in the schematic looks like an arrow, thats the direction the current will flow. in the opposite direction it blocks. And current always flows from positive into negative in a circuit. The protection diode over the motor must always be placed backwards (so it doesn't passage when motor should be on and fry the transistor!) as seen in the schematic.

I still can remember that I was new into electronics and this kind of basic circuits, and it took a long time, and lots of fried components :) and hours of thinking and frustration why it doesn't work as it should. But eventually you succeed and you're the proud owner of your robot that completely drives by itself. So just keep trying.

I try to fix this today, unless i don't have diodes ;(

It looks like your  transistors/LDRs are wired wrong. The LDRs should have one end to V+, the other end to the transistor base.

You should also attach a diode across the motor leads (or any other inductive load) to keep from zapping the 3904.