I have developed a VI for automated pressure application based on NI cRIO using LabView FPGA.
I am using PID VIs for closed loop control. I have a doubt regarding the usage of PID setpoint profile VI. I am storing the setpoint profile as an array of clusters (time & setpoint) and to the setpoint profile VI, I input a subarray of two clusters (pair) at a time so that I can have a control over setpoint profile.
I give command to go to the next or previous pair of clusters from the user interface. But the control is not working as expected. I have ensured that the correct pair is fed as input to PID setpoint profile VI, but there seems to be an issue with the time for ramping.
I understand that the setpoint profile VI needs time profile to be mentioned in the ascending order. But is this requirement only for the immediate array given as input or whether all the time values are given at various times needs to be in ascending order?
I hope my question is clear. Thanks in advance
The issue is solved. The addressing of the setpoint array was made run time by using a shift register and the time input was programatically made in the ascending order.
Application working as required after making the above change.