How do I set up a triggered analog output on a USB 6009?

[chowph]

Hi! I am very new to LabView and am working on the control portion of my senior ME design project. It is an anti-tip brake system for a bicycle. The goal is: When critical time to tip is reached (by reading values from a rear wheel normal force sensor, taking the derivative and calculating this critical time), my cheap DAQ USB-6009 device will put out an analog signal to a transistor, which will spin a DC motor (attached to a worm gear setup) for a certain length of time (...This will change a pivot location in the mechanical assembly which will decrease brake mechanical advantage).

I have been trying to work with LabView 8.5. I get bogged down in confusion when I try to use G-code and get unexplained errors in using Express VI's (they're rather black box-ish to me).

I think that all I need to do is set up an analog input channel, take derivatives and values and put them into a formula for critical time. Then if the result is a "True", I want to begin an analog out sequence for a certain period of time (to get the motor to the right position).

I would appreciate any help that I can get with this one.

[ryannorthington]

chowph,

You are correct with your last statement about performing a comparison on your data.

1.  Are there any error codes or messages in the errors you are getting? Or if you have screenshots of the errors you could post then that would work too.  Knowing the errors would help in understanding where to start. 

2.  In your previous post did you have a chance to try the examples or Kent’s example code he posted?

3.  What were the results of those examples and your experiment?  Again screenshots would work fine here.

Since you new to LabVIEW make sure to take advantage of the online training material and tutorials we have on ni.com.  I have posted a few that I think may be helpful.

Learn 10 Functions in NI-DAQmx and Handle 80 Percent of Your Data Acquisition Applications

Complete Data Acquisition Tutorial

How Can I Learn LabVIEW?

I hope this helps!!

Message Edited by Ryan N. on 03-31-2008 11:52 AM