How do I add a node to a simscape custom component?

I am building a custom component, I would like to create an internal thermal node inside of the component, what is the best way to do this?

Right now I have to create a node on the outside of the part

Is there any way to create nodes from the library? Or do I need to create variables? I have also tried creating a node from a variable, but that also did not work

I am working from this example: https://www.mathworks.com/help/physmod/simscape/lang/defining-relationship-between-component-variables-and-nodes.html

but in this example they are using a domain. I am unsure of how to integrate a domain into a component.

Again my question is how do I create a non-visible node inside of a custom component?

nodes %conserving ports
 p = foundation.electrical.electrical; % +:top
 n = foundation.electrical.electrical; % -:bottom
 Th = foundation.thermal.thermal; % H:top 
 Tc = foundation.thermal.thermal; % C:bottom
 Tm = foundation.thermal.thermal; % M:bottom
end

parameters
 dTmax = {63, 'K'};   % DeltaT Max constant from datasheet
 Km = {0 , 'W/K'}; % Thermal conductivity
 Rm = {0 , 'Ohm'}; % Resistivity 
end

function setup  
    qE = {value={0,'J/s'},priority=priority.low}; 
    qR = {value={0,'J/s'},priority=priority.low}; 
    qS1 = {value={0,'J/s'},priority=priority.low};
    qS2 = {value={0,'J/s'},priority=priority.low};

      Th.T =  {value={0,'K'},priority=priority.low};
      Tc.T =  {value={0,'K'},priority=priority.low};
      Tm.T =  {value={0,'K'},priority=priority.low};
  end

% Parameter validation.
branches
 i  : p.i -> n.i;

   qR : * -> Tm.Q; %This is for self heating, its a heat source from ground 
   qS1 : Tc.Q -> Tm.Q;
   qS2 : Tm.Q -> Th.Q;
   qE : Tc.Q -> Th.Q;

end

equations
 qR == Rm * i * i;
 qS1 == (Tc.T - Tm.T)*Km/2; 
 qS2 == (Tm.T - Th.T)*Km/2;
end

Answer 1

[Steven]

Figured it out, you do it this way

nodes(Access=private)
 Tm = foundation.thermal.thermal; 
end