Asked by veeresh g
on 13 Sep 2019

clc

clear all

%This is the programme with parameterssuggested by the somaye

m1=5.5 ;m2= 20;m3=4.17;m4= 9.337 ;m5=15.853 ;m6= 5.807;

k1=49340 ;k2=20000;k3=10000;k4=134400 ;k5=2916 ;k6=146640;k7= 68064;

c1=2475 ;c2=330 ;c3=200;c4= 250;c5=316;c6=3252.9;c7=1606.3;

M=[m1 0 0 0 0 0 ;0 m2 0 0 0 0; 0 0 m3 0 0 0;0 0 0 m4 0 0;0 0 0 0 m5 0;0 0 0 0 0 m6];

K=[k1+k2+k7 -k2 0 0 -k7 0; -k2 k2+k3 -k3 0 0 0; 0 -k3 k3+k4 -k4 0 0; 0 0 -k4 k4+k5 -k5 0;-k7 0 0 -k5 k5+k6+k7 -k6; 0 0 0 0 -k6 k6];

C=[c1+c2+c7 -c2 0 0 -c7 0; -c2 c2+c3 -c3 0 0 0; 0 -c3 c3+c4 -c4 0 0; 0 0 -c4 c4+c5 -c5 0;-c7 0 0 -c5 c5+c6+c7 -c6; 0 0 0 0 -c6 c6];

W = 2*pi*[0.5 0.63 0.8 1 1.25 1.6 2 2.5 3.15 4 5 6.3 8 10 12.5 16 20];% Experimental frequency range in radians

p=zeros(17,1);

x=zeros(17,1);

x1=zeros(17,1);

q=zeros(17,1);

y=zeros(17,1);

y1=zeros(17,1);

r=zeros(17,1);

z=zeros(17,1);

z1=zeros(17,1);

[rows columns] = size(W);

for i=1:columns % Retriveing number of frquencies

A= (-W(i)^2*M+j*W(i)*C+K);

B=[k1 c1; 0 0; 0 0; 0 0;0 0;0 0];

a = [1.01 1.01 1.01 1.02 1.03 1.06 1.08 1.1 1.16 1.29 1.45 1.23 1.01 0.96 0.86 0.71 0.63]; % Experimental results of seat to head transmissibility.

% b1= abs([0 0 0 0 0 1]*inv(A)*B*[1; j*W(i)]); % Analytical calculation of seat to head trasnmissibility.

%

% p(i)= abs(b1);

% x(i)= (p(i)- a(i)); % Difference between analytical and experimental STHT values.

% x1(i)= (x(i)^2); % square of the Errors.

end

Answer by darova
on 13 Sep 2019

Accepted Answer

These matrices look like symmetric except:

>> C-C'

ans =

0 0 0 0 0 0

0 0 0 0 0 0

0 0 0 0 316 0

0 0 0 0 0 0

0 0 -316 0 0 0

0 0 0 0 0 0

>> (K-K')/1000

ans =

0 0 0 0 0 0

0 0 0 0 0 0

0 0 0 0 2.9160 0

0 0 0 0 0 0

0 0 -2.9160 0 0 0

0 0 0 0 0 0

Giving only 6th root?

b1= abs([0 0 0 0 0 1]*inv(A)*B*[1; j*W(i)]); % Analytical calculation of seat to head trasnmissibility.

darova
on 26 Sep 2019 at 8:12

Thank you. It surely will help somebody

darova
on 26 Sep 2019 at 8:19

Also, this part can be shorter

% p=zeros(17,1);

% x=zeros(17,1);

% x1=zeros(17,1);

% q=zeros(17,1);

% y=zeros(17,1);

% y1=zeros(17,1);

% r=zeros(17,1);

% z=zeros(17,1);

% z1=zeros(17,1);

[p,x,x1,q,y,y1,r,z,z1] = deal( zeros(17,1) );

% M = [m1 0 0 0 0 0 ;0 m2 0 0 0 0; 0 0 m3 0 0 0;0 0 0 m4 0 0;0 0 0 0 m5 0;0 0 0 0 0 m6];

M = diag( [m1 m2 m3 m4 m5 m6] );

veeresh g
on 27 Sep 2019 at 10:25

thanq

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## darova (view profile)

## Direct link to this comment

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## veeresh g (view profile)

## Direct link to this comment

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