1.2 Obtain the step response of an LTI from its transfer function

Problem: Find the unit step response for the continuous time system defined by the transfer function \[ H(s) = \frac {25}{s^{2}+4s+25} \]

Mathematica

Clear["Global`*"]; 
 
tf=TransferFunctionModel[25/(s^2+4s+25),s]; 
y = OutputResponse[tf, UnitStep[t], t]; 
 
Plot[Evaluate@y, {t, 0, 4}, 
 PlotRange -> {{0, 4}, {0, 1.4}}, 
 Frame -> True, 
 FrameLabel -> {{"y(t)", None}, 
                {t, "step response"}}, 
 GridLines -> Automatic, 
 GridLinesStyle -> Dashed, 
 ImageSize -> {300, 300}, 
 PlotStyle -> Red, 
 AspectRatio -> 1]
 

pict

 

Matlab

clear all; 
s     = tf('s'); 
sys   = 25/(s^2+4*s+25); 
[y,t] = step(sys,4); 
 
plot(t,y,'r'); 
xlim([0 4]); 
ylim([0 1.4]); 
title('step response'); 
xlabel('t'); 
ylabel('y(t)'); 
grid 
set(gcf,'Position',[10,10,310,310]);
 

pict

 

Maple

restart: 
with(DynamicSystems): 
sys := TransferFunction(25/(s^2+4*s+25)): 
ResponsePlot(sys, Step(),duration=4);
 

pict