Show Posts
Pages: [1]
1  Using Arduino / Project Guidance / Re: Arduino to control switches on: April 08, 2011, 01:24:47 pm
Not sure what your overall objective is, but you may want to design with the intent that the water is removed from the surface as it condenses and not allow it to freeze on the surface.

I would agree with this, since I built something almost exactly like what you are doing.  I had a peltier cooler hung with a heatsink on it so that it would drip over a funnel with a small hole into a reservoir.  This was with a 60 watt cooler and due to the constant flow of water, it would not freeze.

It would collect about 1/4 cup in 2 hours in my 90deg 90% humidity garage.

This would simplify your project a bit.  The addition of a small fan would also help prevent freezing on a more powerful unit, as would a larger heatsink.

Also, if you don't freeze it and use a fan to circulate the air, you can route the excess cold air from the cold surface to the hot side, making it more efficient.
2  Using Arduino / Project Guidance / Re: Arduino Air Pump on: March 31, 2011, 04:41:34 pm
You could use this:
http://www.sparkfun.com/products/10398

Since it holds a vac, I would assume it will hold pressure too.  And you could reverse it to deflate the balloon if you wanted.
3  Using Arduino / Project Guidance / Re: tonfa, police stick measuring hits and impact on: February 23, 2011, 01:41:31 pm
I am also new to the arduino.

But I can give you some guidance.  Starting looking for a G sensor with very high G ratings.  The end of a baton can be going very fast when it hits something, and it will stop in a few milliseconds.

This would be a good starting sensor:
http://www.sparkfun.com/products/9332

If you make the grip so that they hold it the same way each time, you might be able to get by with 2 of those or a high G 2 axis if you can't find a 3 axis( poking someone is likely not that much of a concern).

You might have to worry about the crystal oscillators, the standard ones that arduinos have might start to fail after a few hard hits.
A hard enough hit could cause the Atmega chip to reset or act strange.
Make sure all your components can survive 300gs, if not put them as close to the handle as possible.
Pages: [1]