How to create an input signal from acquired data

Hi to all.

I want to create an input signal (wich I use to build with the 'Signal builder' block) from data I acquired. I have this data in a .xls and have already learned how to import it to the 'Workspace'.

Hope you can help me, Cheers

Answer 1

[Laura Proctor]

If your data is already defined in the workspace, then you may use Inport blocks found in the Sources Library to import each signal. Each signal must be a column-wise vector, and you must define the variables to import from the workspace in the Configuration Parameters (CTRL+E) > Data Import/Export Tab. Check the Input box and then add your input vectors. For example, if you have 3 input vectors defined in the workspace named u1, u2 and u3, your Input field would look like this: [t u1 u2 u3]. You may have all of your data in a matrix. In this case, each column represents a different input. If the matrix is named data, you would enter [t data] in the input field.

[Frederico]

Hi Laura,first of all thanks for your help.

I could manage to make it work the way you told me.I tried with single vectors.

Is the 't' variable I'm importing giving now the time parameter for my simulation?Imagine my simulation would be running with a frequency of 10Hz, if now my 't' input has 50Hz this will be the new frequency of my simulation?

[Laura Proctor]

Your simulation frequency and time will be independent of your input frequency and time depending on the solver that you use and the time that you set for your simulation.

Answer 2

[Guy Rouleau]

Laura's solution is one good approach.

If you want to import your data directly from Excel to the Signal Builder block, follow this example:

http://www.mathworks.com/help/toolbox/simulink/gs/bsmigir.html

[Frederico]

Hi Guy,thanks for your answer.

There's no "Import" option under "File"...in the "Signal Builder".All I see is under File is Open,Save,Export,Export to Workspace,Simulation Options.I'm using Matlab R2008b