HOW CAN I TURN AN EQUATION INTO COMPONENT IN A LIBRARY?

component CantileverBeamDeflection

% Define the nodes

nodes

P = foundation.mechanical.translational.translational; % Translational node P

C = foundation.mechanical.translational.translational; % Translational node C

end

% Define the parameters

parameters

L = {1, 'm'}; % Length of the beam

E = {210e9, 'Pa'}; % Young's modulus

I = {1e-6, 'm^4'}; % Second moment of area

w = {100, 'N/m'}; % Uniform load per unit length

x = {0.5, 'm'}; % Distance from the fixed end

end

% Define the variables

variables

delta = {0, 'm'}; % Deflection

end

% Define the equations

equations

% Deflection equation for a fixed-free beam under uniform load

delta == (w*x^2)/(24*E*I) * (L^3 - 2*L*x + x^2);

% Force equilibrium at nodes

P.f == -w * x;

C.f == w * x;

end

end

Answer 1

[Yifeng Tang]

Hi Usha,

In addition to Ayush's answer, I suggest that you look at the source code of a translational spring block. You custom block seems to missing equations between port velocities (across variable) and internal displacement (delta). The equations for the force (P.f and C.f) seem a bit problematic as well to me. Usually the force is the difference between those at the port. What you have seems to assume one end is fixed to the ground. I understand it's usually how a beam works, but defining the equations with such assumptions (in your mind) may confuse Simscape :p

Answer 2

[Ayush Aniket]

Hi Usha,

To turn an equation into a component in a library in Simulink, follow the below steps:

1. Save the Simscape file ( .ssc) with the component defnintion (as mentioned above in the question) in a directory that's on your MATLAB path. You should defind the component's physical nodes, parameters, variables, and equations within the file. Follow the guidelines as given here: https://www.mathworks.com/help/simscape/lang/creating-custom-components.html#brnos_c-4
2. The next step is to organise your component file in namespace folders. You should save the file inside a folder on the MATLAB path and the name of the folder should start with a '+' character for e.g. '+MyComponents'.
3. The last step is to build the library to make your component available in Simulink. You can do this by using the ssc_build function. For example, if your component is saved in a directory named '+MyComponents', you would call ssc_build MyComponents.

Refer to the following documentation link to read in detail about the steps: https://www.mathworks.com/help/simscape/lang/building-custom-block-libraries-from-simscape-component-files.html