numerical integration to obtain response using convolution

%% Question - I have to integrate this expression symbollically such that the final answer is a function of ta
%% because I have to plot response v\s ta , but I am getting a symbollic expression
syms ta tau 
m = 2;
wn=707.10678;
wd = 707.10236;
z=0.003535;

F = -8.492 -18.92 *cos(ta*4) + -7.036e-14 *sin(ta*4) + -11.03*cos(2*ta*4) + -8.148e-13*sin(2*ta*4)+-9.687 *cos(3*ta*4) + -7.713e-13 *sin(3*ta*4) + -9.277*cos(4*ta*4) + -6.027e-13*sin(4*ta*4)+-4.587 *cos(5*ta*4) + 5.084*sin(5*ta*4);
response = 1/(m*wd)int(F*exp(-z*wn(ta-tau))sin(wd(ta-tau)),tau,0,ta);
pretty(response)
subs(response,3.5)            %% Tried finding the value at ta = 3.5

%% plot response at some 4-5 valuse of ta

Answer 1

[Alan Moses]

The code attached produces an error due to missing multiplication operators. You may replace the line 10 of your code where the 'response' variable is calculated with the below line:

response = 1/(m*wd)*int(F*exp(-z*wn*(ta-tau))*sin(wd*(ta-tau)),tau,0,ta);

You may also check out the vpa function that substitutes the value of 3.5 to the ‘response’ symbolic expression. You may use the following line of code:

vpa(subs(response,3.5))

Hope this helps!

[Shubham]

Very helpful now I am able to plot