%% Function name
%       qqbar

%% Revised
%       30 January 2014

%% Author
%       Shyam Ramanath Thillainathan, Trey Moore, & Autar Kaw
%       Section: All
%       Semester: Fall 2013

%% Purpose
%       Given the four elastic moduli of plies, E1, E2, 
%       nu12,G12, angle of plies and number of plies this 
%       function calculates the Reduced Stiffness Matrix, Q 
%       and the Transformed Reduced Stiffness Matrix Qbar of the plies.

%% Usage
%       function [Qplies,Qbarplies] = qqbar(nplies,moduliplies,angleplies)
% Input variables
%       nplies=number of plies
%       moduliplies=vector of elastic modulii and Poisson's ratio for each lamina
%       E1=longitudinal elastic modulus
%       E2=transverse elastic modulus
%       nu12=major Poisson's ratio
%       G12=in-plane shear modulus
%       angleplies=angle of ply in degrees for each lamina   
% Output variables
%       Qplies=reduced stiffness matrix for each lamina
%       Qbarplies=transformed reduced stiffness matrix for each lamina
% Keyword
%       reduced stiffness matrix
%       transformed reduced stiffness matrix

%% License Agreement
%       http://www.eng.usf.edu/~kaw/OCW/composites/license/limiteduse.pdf

%% Testing code
clc
clear all
%% Inputs
% Material: Graphite/Epoxy
% Lamina: 60/45/45/90
nplies=4;
moduliplies=[181E9 10.3E9 0.28 7.17E9; 181E9 10.3E9 0.28 7.17E9; 181E9 ...
             10.3E9 0.28 7.17E9; 181E9 10.3E9 0.28 7.17E9];    
angleplies=[60 45 45 90];
fprintf('Number of plies: %g\n',nplies)
for i=1:1:nplies
    fprintf('\nFor Ply: %g\n',i)
    fprintf('\n   Angle of Ply: %g\n\n',angleplies(i))
    disp('   Angle Lamina Engineering Constants')
    disp('___________________________________________')
    fprintf('\n E1   | %G\n E2   | %G\n nu12 | %G\n G12  | %G\n\n'...
    ,moduliplies(i,1),moduliplies(i,2),moduliplies(i,3),moduliplies(i,4))
end
%% Test
% Call function: qqbar
[Qplies,Qbarplies] = qqbar(nplies,moduliplies,angleplies);
for i=1:1:nplies
    fprintf('\nFor Ply: %g\n',i)
    fprintf('\n   Angle of Ply: %g\n\n',angleplies(i))
    disp('   Reduced Stiffness Matrix')
    disp('______________________________________________')
    disp(Qplies(:,:,i))
    disp('   Transformed Reduced Stiffness Matrix')
    disp('______________________________________________')
    disp(Qbarplies(:,:,i))
end