Page 180 - MATLAB an introduction with applications

Control Systems ——— 165

Unit-ramp response
10

8
Unit-ramp input
6
Output

4 Output

2

0
0 2 4 6 8 10
t Sec
Fig. E3.17(a) Unit-ramp response curve

>> %Input r1=exp(–0.7t)
>> num=[0 0 1 12];
>> den=[1 5 8 12];
>> t=0:0.1:12;
>> r1=exp(–0.7*t);
>> y1=lsim(num,den,r1,t);
>> plot(t,r1, ‘–’, t,y1, ‘o’)
>> grid
>> title(‘Response to input r1=exp(–0.7t)’)
>> xlabel(‘t Sec’)
>> ylabel(‘Input and output’)
>> text(0.5,0.9, ‘Input r1=exp(–0.7t)’)
>> text(6.3,0.1, ‘Output’)

F:\Final Book\Sanjay\IIIrd Printout\Dt. 10-03-09