My gf is from the country and has an unnatural love for water pump windmills - google those three words if you don't know what I'm talking about
So, I firstly realised my making-things skills have gone far down hill, and I'd need to do a practice run first. Enter the Tiny Windmill Mark 1
My end goal for Mark 2 will be a legit windmill that powers a little LED or what have you when you blow on it, with the option to power it off a battery as well - great thing about DC motors, you can use them to power stuff, or you can use them to generate an electric current. Magnets man...how DO they work
I decided to use a little iPhone 5 vibration motor seeing as I have like 3 lying around. The rest of the bits I scavenged from whatever I could find around my desk. At this point all I really want is to get a basic build up to get a feel for the motor and what it can handle, and maybe some design elements so I have a better idea of how to approach things for Mark 2.
Used this thingy for the blades:
Bent some paperclips around a screwdriver and a whiteboard marker and used a bit of blu-tak to hold it in place while I did some messy soldering:
Found a weird ball-joint thingy and made a crude stand out of some stiff wire
Et Voila, windmill
I bent one of the motor pins down and soldered it to its metal outside casing, that way I only need to run 1 wire down from the motor to the coin cell battery at the bottom, and the frame becomes the other "wire".
And she runs! Albeit wayyy too fast
this motor doesn't have a lot of torque, but it's got some damn fast RPMs so I'll definitely need to limit this. I was going to use a resistor, but I think the low torque of the motor would mean it might never start spinning, so PWM it is. I'll use a cheap 555 to generate my PWM cycle. PWM just means instead of a continuous "on", you have a signal that goes on/off in a ratio defined by you. 90% on and 10% off means the motor would run at near full speed. 10% on and 90% off means it'll run very slowly.
Seeing as this motor is so freakin' tiny, I definitely won't need a beefy power transistor to drive it, so I'll drive it directly from the output from IC555's pin 3 and ditch the rest of it. Cuts down price too
By far the most expensive part would be the 100k Pot (like $3 here) so I'll see if I can scavenge one off an old piece of junk somewhere. The rest of the parts cost about 10 cents each with the execption of the IC which costs $1.30
Total cost for the project so far: $2
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