solve 4th order ode in simulink

I need help solving PART B of this problem. I have never worked with ODE's before. I have attached what i have so far.

[James Tursa]

You've never worked with ODE's before, and your first forray is a 4th order system that you have to solve with ode45 and with Simulink? What class is this for?

Answer 1

[Jim Riggs]

Your diagram looks reasonable to me and it could work, but its hard to tell from a screen shot - especially when the block titles are not being displayed, so I have to guess at what each block really is. Assuming that the sine wave block is set to "time based" and "use simulation time", with an amplitude of 10 and a frequency of Pi, it should work.

It also looks like you used the "scope" block in place of the "xy graph" block, which was specifically stated in the instructions. (but that would be my preference as well).

[Jim Riggs]

After some thought, I think that the use of the sine wave block is not consistent with using the XY Graph block. I think that in order to use the XY Graph block, you will need to have a time signal, in which case I would construct the sine wave as follows, using a clock block, rather than the sine wave block. This gives access to a time signal.

[Christian Diaz]

I’ll try it out, thanks!

[Jim Riggs]

My point is that the instructions specify both the sine wave block AND the XY Graph block. I don't think it makes sense to use these together. Either:

1) the clock + XY graph, or

2) the Sine wave + scope.