Manish, Russ is correct. You should be able to accomplish this in LabVIEW. What you described sounds like a simple control loop. Below is an example of a basic PID control loop that acquires some data, analyzes it, then outputs an appropriate value depending upon the input. This is a good starting point for your application.
<a href="http://sine.ni.com/apps/we/niepd_web_display.display_epd4?p_guid=B45EACE3D88156A4E034080020E74861&p_node=DZ52338&p_source=External";>PID example</a>
