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[on:]

This is the thermometer, driven by Arduino Nano, servo motor and Yahoo weather API. The hand can show current temperature either at the upper or at the lower quadrant, depending on the weather forecast. Upper quadrant is used when the temperature is rising, lower when falling.

[Reply #1 on:]

Hi, BIG dials are cool...

I have made some with simple materials also.. Foamcore board and foamcore pointer for example.  Or cardboard. Or ???

If you balance the pointer (equal weight to left and right of pivot point) even small servos like those below will work. So only one Arduino pin needed per dial. (The straw stuck on the standard servo arm in the photo is so light it's No Problem).

Here's an example sketch that you could use to test.. It uses a potentiometer which you can turn by hand to see the servo action follow it.
http://arduino-info.wikispaces.com/YourDuinoStarter_ServoPotPosition

See the Map function in that code. You could figure out how to map the parameter you want to "Meter" to servo movement. Maybe output the servo data to Serial Monitor and 'calibrate' the marks you make on the dial.  See: http://arduino.cc/en/Reference/map

DISCLAIMER: Mentioning stuff from my own shop... but you can get these lots of places..

http://goo.gl/Ys5pp    small servo
http://goo.gl/n6aVL   10K Potentiometer  

[Reply #2 on:]

Thank you for the great idea, using foamcore for the dial!
I'm using  this servo (http://goo.gl/Ys5pp) in my project, encountered one problem: for some angles it continues to make annoying buzzing noise even after it stops moving. I have solved it by sending attach() and detach() commands for each rotation.

[Reply #3 on:]

I have solved it by sending attach() and detach() commands for each rotation

That's a good idea! Also should reduce the power used somewhat. If the pointer is balanced the servo should hold position with power off, no problem..

[Reply #4 on:]

Aha! it uses a servo, I thought it was the twin sister behind the wall turning the "thermo"-finger;)

More serious, well done
and there is room for more weather info !

[Reply #5 on:]

Even though my wife is not a tall person, she has practiced karate for quite a while so I wouldn't risk trying to fit her inside our ikea closet.

I thought about adding some LEDs with precipitation forecast, but we are happy as it is now.

Thank you for the thumbs up!

[Reply #6 on:]

but we are happy as it is now

Simplicity is a strong design paradigm!