Velocity PID Programming: Terms dependent on time

[simpsonboy77]

I'm not certain about labview's implementation but in C++ you can request the system clock for its time since it powered up. This has a resolution of 1ms. Before you do your dt calculation you can figure out how much time has passed by asking for the current system time and subtracting the last time you asked for the time. I think this is much better than any loop that you state how long it takes. This will account for anything that changes the cpu load, perhaps vision code or the garbage collector.

new_time = current_sys_time
do pid calculations with dt = new_time - old_time
old_time = new_time