LabVIEW file (subVI):
What is it?
The subVI implements an integrator based on the Explicit Euler, or Forward, method of discretization. A typical use is shown in Figure 1 (from inside a While loop).
Inputs to the function:
Outputs from the function:
How to include the integrator in your block-diagram?
RecommendationWhen you include the Integrator in a closed loop of functions in the block diagram, LabVIEW may identify the loop as an algebraic loop and therefore insert, automatically, a Feedback node in the loop to break the algebraic loop. I recommend that you place the Feedback node just before the input (u) to the integrator, which is actually the time-derivative of y. The Initializer terminal of the Feedback node can be left unwired (hence the initial value of the time-derivatie is zero, which should be fine). Figure 1 (above) illustrates this.
Why this subVI?
The reason why I have developed this subVI, is that the inbuilt integrators in LabVIEW do not have sufficient functionality for dynamic simulators, or can not be used, or are complicated to use, in ordinary While loops.
Updated 30 August 2016 by Finn Aakre Haugen