Using the dPressure 500 VI in LabVIEW


#1

Is there any documentation available or examples of programs for the dPressure 500 VI in LabVIEW? The manual on the product page (http://www.dexterindustries.com/manual/lego-mindstorms-sensors/dpressure/?PageSpeed=noscript) only seems to cover use within LEGO MINDSTORMS software. I’m able to download the VI file and drop the VI it into LabVIEW 2013, but more information on how it integrates into a program would be helpful.


#2

Sure, no problem! Just a heads up, we don’t have any experience with LV 2013.

When you open up the VI, does it look like the attached picture?


#3

I don’t seem to be able to access the block diagram for the dPressure 500 VI. I can see the front panel when I click on the icon, but when I try to go to the block diagram it prompts for a password. I’ve attached screenshots of what I see when I drop the VI into LabVIEW and when I click to open the dPressure VI. Thanks!


#4

We must still have the locked version up on FTP. I will replace.

In the meantime, here’s an unlocked version. Also attached is a datasheet for the sensor, just for background.

You integrate it into a LV program by importing it, and selecting which port you want to read from. Your output on pressure comes out in raw (analog reading) value, kilopascals, and PSI.


#5

Sorry, our own forums won’t let us upload the file for security reasons. Doh.

I’ve re-uploaded the file here:
http://www.dexterindustries.com/files/dPressure_500.vi

Can you tell me if you can download it?


#6

Great! Thanks - I am able to download the unlocked version and can see the block diagram in LabVIEW.


#7

Very good. Hopefully this helped?

Can we ask what you’re working on?


#8

It’s definitely helped - My experience with LabView is limited, so I’m also learning that as I go! Trying to figure out how to process the signal from the sensor and using it to control a motor. My end goal is similar to what is in this document (though I’m using NXT components instead of RCX):
It’s a PID process control demo with a water flow system and a small tank. The pressure sensor signal (at the bottom of the tank) will tell the motor whether to open or close the valve to either keep the level constant or change the level based on the user’s input. I’m a grad student TA working on this for a class, so the demo will ultimately be used with undergraduate chemical engineering students!


#9

Oops - Looks like the link didn’t post. Another try: http://www.ni.com/pdf/academic/us/journals/Design_Build_Test.pdf


#10

Your story is quite interesting. My first experience with Labview was as a Grad student doing research for my thesis in a lab, monitoring pressures on an artificial kidney, for my MS in Chemical Engineering. Ha!

I hated labview so much, it was such a painful experience, that it stuck with me for a few years as I worked on another startup and had a few adventures in between. I came back and started Dexter Industries to solve that problem. We’ve wandered way off course since then.

Good luck. If we can help at all any more, let me know!