Let's Make Robots!

Autonomous Recycling Robot

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dallaby's picture

   I would love some more information on the electric wire fence... Schematics,links whatever you can provide.. I have spent months trying to get it to work properly with no real results.

madsci1016's picture

The fence itself was provided to use as part of the competition. I do know it was a 10kHz sawtooth wave. I think they used an Op Amp or two to generate the sawtooth wave, and then ran that through the wire loop, and through a resistor in series with the loop. The current through the loop at 10kHz is what generates a detectable EM field.


I did design that sensor we used to pick up the wire. I'd have to really dig for the schematic, but I can tell you about it. The sensor probe itself is an inductor. The EM field generated by the wire fence will cause a current to generated in the inductor, which we tie a resistor across the two inductor leads so the current creates a voltage across the resistor. That voltage difference is amplified by an Op-amp, and then filtered by a bandpass filter set to pass only the 10kHz signal. Then we rectify and limit the signal to 5V using diodes and read it with an ADC pin on the Atmega. 

OddBot's picture

Do you have any actual information on this robot? Photos, schematics, code etc? If this is only a link to a video then it doesn't really meet the requirements for a robot page.