Hey fellas, Simple problem here, but I can't seem to figure it. I'm trying to write two equations and combine the two before plotting the resulting time function.
For the first element:
w0 = 1; %rad/s%
zeta = 0.15; %damping ratio%
wn = (w0)/((1-(zeta^2))^(1/2));R = 1;num = (wn^2);den = [1 (2*zeta*wn) (wn^2)];Ideal = tf(num,den);t=0:0.1:30;step(R*Ideal,t);axis([0 30 0 2]);stepinfo(Ideal)This strip will result in a plotted step response of a transfer function in the S domain. If my other equation is in the time domain, one must 'laplace' yes?
a = 0;b = 1;c = 6;T = 0.1;% Conversion to 'sym' from 'tf' is not possible.
G = a+(b./(1+exp(c*(T-t))));S = laplace(G);Y = S*Ideal;y = ilaplace(Y);With all input variables given except 't', one would think it's a simple matter to just laplace it and multiply the two in the S domain before ilplace back, but I've encountered three errors, each at different points:
Undefined function 'laplace' for input arguments of type 'double'.Undefined function 'transform' for input arguments of type 'char'.and, if we 'which laplace -all' and enter the function manually, we get
Error in laplace (line 28)L = transform('laplace', 't', 's', 'z', F, varargin{:});Eventually I want to plot the resulting function between these two; is there any insight on this issue?
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