I have made a block in Simulink that calculates some Aerodynamic coefficients.
I had like to use this coefficients in order to define the numerator and denominator of a transfer function.
Is there a way to link between the output from the coefficients block to the transfer function?
Thank you
No. The output of your aerodynamic block are signals. The numerator and denominator of the Transfer Function are parameters. You cannot use signals as parameters, or vice-versa.
What you can do is construct your own transfer function using an appropriate arrangement of Sum, Product and Integrator blocks, with the signals from your aerodynamics block being used (typically in conjunction with the Product blocks) to define the appropriate coefficients/gains.
Related
How to make block arrangements in Simulink to convolute 2 continuous input signal?
For some reason, I have to be able to reset the convolute integral accumulation. Hence, I can't use the conv block in Simulink. Nor can't I use a transfer function block.
This is what I have tried so far. But it only match with the conv block for the first 0.5 second. It then jumps up and down randomly. I know that the implementation I have tried is not continuous, but I don't know how to implement it continuously: whether it is possible to integrate with respect to some other variable other than time in Simulink.
I have a transfer function with a coefficient in the denominator which value changes with the output of the model.
So the question is: How to set a transfer function in simulink with variable coefficients?
It should be done with the block transfer fcn Direct Form II Time varying.
Can anyone explain to me how it works? There is not enough informations concerning this block in the Matlab Documentation! An example would be very helpful .. Thanks
I want to be able to externally have inputs for the lower passband edge frequency and higher passband edge frequencies for the butterworth filter block in the simulink signal processing toolbox in matlab. How can I achieve this. Currently you'll have to click the block to specify these frequencies and this is not possible at runtime.
Regards,
Alfred
Basically you are asking for a filter that has time varying parameters. The Butterworth filter block does not allow for this, and cannot be modified to do so, so you are going to have to roll your own. This can be achieved in several ways:
Determining the difference equations that you need to implement, then creating a filter out of fundamental blocks (product, summation and unit delay blocks) where the "parameters" you want to change are fed into the product blocks as signals.
Using a block such as Transfer Fcn Direct Form II Time Varying. (This assumes you can parameterize the changes you need as a gain-scheduled signal.)
Write an S-Function (or perhaps a MATLAB Function block) to implement any detailed/specific functionality.
I'm trying to build a Simulink model containing a "s-function block" simulating a continuous process with a "Matlab Function Block" that use the input and output from s-function.
But I need the input to the "Matlab Function Block" with differents values of the same signal over time. That is, a vector with different sampling times for each input to "Matlab Function Block". This will be needed for testing identification techniques.
How could I do this?
Thank you
Assuming you are using a fixed-step discrete solver, and that you don't have too many values of the same signal to hold, you could use Unit Delay blocks to get the value of the signal at previous time steps. You can then mux all these signals together to form your vector input. Obviously, the practicality of it is limited by how many values of the signals you need to have (and buffer).
I am trying to find which element(index) of a multidimensional signal is computed at a specific time in a Simulink model. Assume that there is a multidimensional input signal given to an add block together with a constant so Simulink calculates the sum with the constant for each element of the signal and gives the output as multidimensional signal. I want to know which index of the signal is computed at a time so I can do additional computation. How can I do that?
Do you want to do additional computation during simulation or after? In the latter case, you can save the multidimensional signal to the MATLAB Workspace as a "structure with time" variable. Then do your additional computations by finding the index of the time point of interest and the associated multidimensional data point. In the former case, you can probably a MATLAB function block with two inputs: the output of a clock block and the multidimensional signal. Then do your processing in there using MATLAB code.