Control air nozzles from computer

[BobHammond]

You guys will have to forgive me, but I'm a complete noob.

I would like to control high speed ejector nozzles from a computer, and I'm trying to figure out what equipment I need to make it happen.

I believe that I need something like:

- NI-6509

- Solenoid valves

- air nozzles

- relays?

I want to hook up compressed air to the system to blow compressed air out of the nozzles. The system needs to be able to operate at high speed - like turning the nozzles on and off in 10-20ms or less.

Thanks for any help!

[crossrulz]

How critical is that timing requirement?  10 - 20ms is on the very hairy edge of where I would trust Windows.  Windows systems have A LOT of jitter.  So if you need the accurate timing, you really need to go to a RealTime system such as a cRIO.

[Buechsenschuetz]

10 to 20ms are very tight timing requirements for an electromechanical devices. Even fast relays have a switching time of several milli-seconds until the contacts are reliably settled (AKA contact bounce), and I have doubts whether an electro-mechanical valve will react in 10ms.

However, I think you have to control the current of the solenoid valves with relays. Most relays need a driver current which is higher than the output specs of most digital interface board, so you need some kind of relay driver circuitry, too.

[BobHammond]

I am not actually sure what speed I need. I was estimating 10 to 20 MS, but with some tests I was doing yesterday, I think I probably have more like 20 - 50 MS.

Could somebody suggest a setup that I could use to control air nozzles like this?

[crossrulz]

20 to 50ms response is reasonable with a good computer, assuming you don't need that response time to be really accurate (within 10s of ms).  Otherwise, I would go with something like the cRIO 9066 and a simple DIO module.

[BobHammond]

I'd like to try to do something through Windows first, as the software is much easier to develop. Can someone suggest a specific setup, including any controllers, relays, etc?