[MOC] Autonomous regulated pneumatic compressor

[AlmightyArjen]

Not very special but worth mentioning I guess... I'm working on an automated coal load/unload station for a few Lego trains. There will be some pneumatics in the system and I wanted to build a compressor that supplies the compressed air. I've already done that by switching a compressor on after an x amount of switching of the pneumatic switches for an x amount of time. The disadvantage of this system is that a lot of times the pressure in the system is too low.

A pressure regulated compressor is the answer! So I bought an NXT pressure sensor from Mindsensors and hooked it to an Arduino chip. The chip regulates the pressure in the system: the compressor is activated when the pressure drops below 30 PSI and is deactivated when the pressure reaches 40 PSI, so there's a hysteresis to prevent frequent on/off switching. The compressor has also a display that displays the current pressure in PSI in the system.

The whole thing just needs a 12V or 9V power supply and that's it :)

[kieran]

Very nice, how do you drive the seven segment displays?

[AlmightyArjen]

The display is a module from Sparkfun and it is controlled by an I2C bus. The advantage of I2C is that you only need two wires for the communication. To the same I2C bus is also the pressure sensor connected.

[jaumeBCN]

ouch, wanted to do that, but do not want to use arduinos... (pneumatic engine RC car)

[bjorkan]

like it, very much :) but for me as electronic-letterless AFOL third photo (http://i.imgur.com/hYfSMwW.jpg) looks exactly like this one: http://4.bp.blogspot.com/-SzuPKAaNoXg/UzkbQfdjvUI/AAAAAAAAA-Q/F9OZFBggyR8/s1600/miracle.gif m.