controlcontrol systemMATLABsimulationsimulink
All simulations I've done in simulink as yet have not matrix in their block diagram like the following picture :
and they have block diagram structure like :
for simulating a system that has matrices with variable parameters in matrice ,in its structrue, how can use matrices as block diagram in it?
for example for following system:
I can't set and adapt the dimesnsion of blocks.
I was going about tackling this problem completely wrong. In order to replace the summing block, one must NOT remove the Transfer Function blocks which feed into the summing block and add them inside the script.
A MATLAB Function does not support code generation (and rightly so) such that a transfer function may be implemented inside it. That is why the blocks simply feed into the MATLAB Function as follows.
The script would very simply be:
function y1 = fcn(u1, u2, u3)
x = (u1 + u2 +u3);
y1 = x;
end
Ah HA!. You used a Matlab nonlinear function block, but you're misunderstanding the system equation. The function \$\dot{\vec x} = f(\vec x, u)\$ is coughing up the derivative of \$\vec x\$, not \$\vec x\$ itself. You need to have a function block that just finds \$\dot{\vec x}\$ from \$\vec x\$ and \$u\$, then feeds it to an integrator (Simulink should be able to integrate a vector just fine) and feeds the \$\vec x\$ back to the block, and extracts \$y\$ from it.
Here's a block diagram of what you want to achieve (sorry for the crappy picture). I can't remember my Simulink well enough to say exactly how to do it -- I suspect you can make a multi-input, multi-output block, but if you can't you can make a concatinated input vector with x and u, and concatenate y and x-dot in the output, and use muxing and demuxing to get the data in and out.
Best Answer
If you want to build a block that has matrix operations there are to blocks that will let you do this, the Fcn block and the MATLAB function block, you can
You can carry through matrices with signals as shown below. The example shows a 1x3 vector multiplied by itself and displayed in the scope as a 3x3 matrix.
Care must be taken to ensure size is preserved for the matrix operation
But the math you have shown above does not make sense, as you should either be creating two states (for example \$x_4\$ should be split into two states) OR you should be carrying the \$x_4\$ through to simplify \$\dot{x_4}\$ to a scalar in your analysis of the system. Usually states are scalars at least with my experience with nonlinear control.
$$\left( \begin{bmatrix} u_2 \\ u_3 \end{bmatrix}+ \begin{bmatrix} \frac{-l K_4}{l_1} & 0 \\ 0 & \frac{-l K_4}{l_1} \end{bmatrix} \right) x_4 $$