Lead-lag system and model with Simulink

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gfd43tg
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Homework Statement


Diagram of a mass M being struck by a hammer on a surface, with an arrow labeled velocity pointing right, and the lead-lag transfer function gp(s) = (s+1)/(s+1) written below.

Simulink block diagram with a feedback loop: a summing junction feeds a Transfer Fcn2 block with (s+1)/(s+1), whose output returns through Transfer Fcn3 block 1/s to the summing junction.


Homework Equations

The Attempt at a Solution


Hello,

I am trying to construct the model, but I don't know how to incorporate 3 steps. I tried making 3 step blocks, but the input for the transfer function will only take one line. Then I tried to use one step block and make a vector indicating a new step at 3 different times
Simulink Source Block Parameters dialog for a Step block, with Step time [1,2,3], Initial value [0,1,2], Final value [1,2,4], Sample time 0, and zero-crossing detection enabled.

Simulink block diagram: a Clock block and a Step block [1x3] feed XY Graph scopes; the Step output drives a Transfer Function block with numerator s+1 and denominator s+1, whose output feeds XY Graph1.

But this is not working, it doesn't like the vector input. Any idea how I can utilize 3 steps?
 
you can use a summing block and three separate step blocks.
There is also an input that will allow you to create your own waveform
 
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Thanks, I didn't know how the sum block worked before, now I do.
 
I am a bit surprised about the transfer function G(s)=(s+1)/(s+1)=1.
Who told you that this is a lead-lag block? It is a unity gain element, nothing else.
 
The homework assignment said, look at the problem statement.
 
Didn`t you realize that G(s)=1 ?
Should be a typing error; why not googling for lead-lag?
 
Yes, admittedly I don't know what lead-lag means. I was just trying to solve the problem for the homework
 
Watch point e) of the problem statement (time constants).
Time constants appear in th transfer function as factors, for eample: (s*T+1).