Instructables
Picture of Adruino Based Electrostatic  Field Mill
How to build your own adruino based electrostatic field mill. I'm going to show you how to build this amazing device that allows you to monitor the amount of electrostatic potential exists around you. Youll be able to watch the electrostatic fields that follow under clouds, occur when you move and walk or even wave your arms! We're going to build this from parts that almost any body has around the house.

Here's a video demo of it in action!
 
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Step 1: Parts Required

Picture of Parts Required
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To build your field mill you'll need the following: An adruino (any model should work) An old processor or case fan from an old computer (it needs to run and be the kind with 3 wires) A couple of the clear CDs that come on the tops and bottoms of cr-r spindle packages One cd any kind A cd-r spindle package Aluminum foil A glue gun Spray adhesive A dead hard drive Some wire

Step 2: Building The Shutters

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A field mill works exposing a plate to the electrostatic field and then measuring it. This is done by a machanical shutter that rotates in front of the measuring electrode. For our shutters we're going to use a couple of clear cd spacers and aluminum foil. First we cover one side of a clear cd spacer with foil. We repeat the process with a second clear spacer. Next we use a ruler to divide each cd's foil into quarters, We then remove the foil on each diagonal quarter. Repeat this process with the second disk

Step 3: Installing The Top Shutter

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To create the shutter system we first mount one shutter to the inside top of the cd package case. The second shutter will rotate below the top shutter thus creating a metal shieldl that will alternately open and close as the second disk rotates below it. Glue the Top disk to the inside top of the CD-r stack case.
raht (author) 1 year ago
Good question! What it does is measure that static electric field. For example. If you have this set in your living room and you walked across the carpet. You'd see the graph vary as you built up a static charge. Then if you touched a doorknob you'd see it drop as the spark kept from your finger to the doorknob. Or, if you didn't touch anything you'd see the graph slowly lower as the electrical potential in your body bled away. Placed outdoors on a pole above the ground and with the open end pointed towards the ground. You'd be able to see the electrical fields generated by cumulus clouds as the drift by. Some clouds have an electrical shadow that follows them. Larger storms do the same thing. When the electrical potential gets large enough. Lightning! Field mills are used as NASA around launch sites to monitor the potential for lightning strikes. I hope this helps explain what it does.
nerd7473 raht1 year ago
thanks for the explanation
nerd74731 year ago
cool but what is it? what is a Electrostatic field mill?
raht (author) 1 year ago
That's supposed to say... Thanks so much!! Goofy spell correct grabbed it! :)
raht (author) 1 year ago
That's so much! I've wanted to build a field mill for a while but all the plans I found were really complex from an electronic point if view. I was sitting messing with a PC case fan whennit hit me that here was a quiet brushless motor with a rotation pulse built in! Once I hooked it up to the adruino to see how the rotation counter worked I thought, " you know the adruino could do everything all the multiplexing and electrolooptical analog plans I'd been seeing for other field mill plans were doing, but in a much simpler and easy to build way! The idea for the CDs came along when I was trying to design a shutter system. After that the project took off!
Thanks for the comments!
vishalapr1 year ago
Such a great project! The waveforms look amazing and quite accurate!