is it possible to give different frequencies input for different time span in simulink ?

Hello,

is it possible to give different frequencies for different timespan in simulink ?

for example my input is F(t) = cos(w*t)

i am simulating for t = 30 secs

for first time span t1 = 0:10 secs my input signal frequency is cos (10*t1)

for first time span t2 = 10:20 secs my input signal frequency is cos (20*t2)

for first time span t3 = 20:30 secs my input signal frequency is cos (30*t3)

how should i do this is Simulink ?

Answer 1

[Azzi Abdelmalek]

You can use a multiport switch block with three sine wave block

set stop time to 29.99

[Aniket]

Ok...but how should i mention the time span for each sine wave block ?

[Azzi Abdelmalek]

Ok I will post a simulink model

[Aniket]

ok thanks

[Aniket]

Hello Azzi i have done this and the frequency changing in the interval of 10 secs. but if i want to change the frequency in the interval of 5 secs i.e t1 = 0 : 5 then how should i do this ?

means in the above structure which parameters affects the changing interval ?

because i try to change value of gain and simulation time but it gives me error as following

********************************

For block 'model1stepinputfrequency/Multiport Switch', control port value '4' is not in between '1' and '3'. To suppress this message and use the default port, you can change the settings of 'Diagnostic for default case' to 'None'

***********************************************

[Azzi Abdelmalek]

how many port are you using? (in the above chart there are 3)

[Aniket]

If i want to use same figure but i want to change my input signal after 5 secs

means for t1 = 0 :5 .... 1 signal

t2 = 5 : 10 .....2 signal

t3 = 10 : 15 ..... 3 signal

and if i want to use more or less data ports ..which parameters changes for control input signal which is fed to multiport switch..

actually i am giving this input to adaptive hopf oscillator using simulink i have implemented equations in simulink ...

[Azzi Abdelmalek]

gain=0.2
stoptime=14.99

Try to figure it out

1. When control port input is between 1 and 1.9999 port 1 passes
2. When control port input is between 2 and 2.9999 port 2 passes
3. and so on