Another fun are litte motor driven units fueled by sunlight:
and it's easily put together: a motor from a old cd-rom drive, some capacitors from an old mainboard and a solar engine (link to www.beam-wiki.org).
the solar panel charges the capacitors up to a level and then the stored energy is released to the motor making the symet to move around.
this was the first try, but the capacitors are way too far above the ground, so this one got a wire coil.
the solar cell is a nice one from schott solar, making the symet to move without direct sunlight, but then it may be as slow as one move a minute ;-)
|this is the second try and this symet is more compact with a cheaper solar cell amd a simple solar engine. as you see just the two npn transistor version with a resistor and a zener-diode. so this one needs sunlight to hop around.|
|and here with the solar cell on top. as spacer to the solar panel two old button cells are just glued in between.|
Some links about symets:
• many sources at Google images
• to the Junkbots Sample Chapter (junkbots.solarbotics.com) an excellent source
• solar engine at beam wiki (www.beam-wiki.org)
And always don't forget: Have fun!
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