MATLAB Answers

Differential equation by simulink

1 view (last 30 days)
Si So
Si So on 10 Jan 2021
Commented: Si So on 11 Jan 2021
Hello everyone,
I modeled a differential equation by simulink. My question is that what is the simulink assumption for initial conditions (necessary to compute the constants, c1 and c2):
For example a typical equation with solution is:
the simulink model is
The simulink result is
I cannot make a comparison between the analytical result and simulink result! I'm not sure if simulink works well... what is the initial condition assumed by simulink and what are the solution constants (c1 and c2)?

Answers (1)

Mischa Kim
Mischa Kim on 10 Jan 2021
Double-klick on the integrator blocks and you'll see that the default initial condition is zero (0). It is also inside the integrator block where you change the intial condition, or, select that it is defined through an external input.
Also, I noticed in your model that the feedback loop starts after the second integrator, while your differential equation contains a Xdot. To make the Simulink model consistent with the equation the loop would have to start between the first and second integrator.
  1 Comment
Si So
Si So on 11 Jan 2021
That's right..., very helpfullllllll feedback, thanks Mischa

Sign in to comment.

Categories

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by