Using Simulink to Solve Ordinary Differential Equations - Part 2

This video demonstrates how to use Simulink (within Matlab) to solve ordinary differential equations (initial value problems). I had to split the video into two pieces because it was a little over 10 minutes. This is part 2. The full video can be found at http://blanchard.ep.wisc.edu/ These videos were recorded for a course I teach as part of a distance masters degree. See http://mepp.engr.wisc.edu

Category:

Science & Technology

Tags:

• Matlab
• Simulink
• Differential
• Equation

[britmegan05]

I am confused about how you are getting multiple links out of the 1st integrator(goes to the 2nd integrator and the multiplier 3). How do you created multiple exits from that integrator?

[jakeblanchard]

@britmegan05

You can create the three objects (the two integrators and the multiplier). Then you can connect the two integrators with a line., Then you can draw a line from the multiplier and connect the other end to the line connecting the two integrators (anywhere between the two objects). It will just connect up, leaving the first integrator with a dual output. Let me know if this isn't clear.

[Ren520]

@jakeblanchard im having the same trouble with multiple links. I tried what you said, and I end up getting a red dotted line. why is this?

[jakeblanchard]

@Ren520

Try this. Start with a blank model. Then put three integrator blocks on the model window. Now connect two of the blocks with a line. Then select both of those connected blocks by drawing a box around both of them. Now hold down the Control (Ctrl) key and trace out a line from the line connecting the first two blocks to the third block. That should do the trick.

[Ren520]

@jakeblanchard thank you very much. What do you use to represent constants? like in your example, dx^2/dt2 = 5cos(2t)-3dx/dt-4x, what if it's

 dx^2/dt2 = 5cos(2t)-3dx/dt-4x + 3? How do i represent the constant 3?

[jakeblanchard]

@Ren520

Use a gain object. It looks like a triangle pointing to the right and it multiplies the input by a constant.

[bisaminkappo]

very2..useful.tq v.much bebey

[dasbuchvonp]

thanks man, you did it again, part 1 and two were effective

[topito2]

nice video!!!! thank you very much

[awhanp]

thanks for the uploads :)