Extracting a response time in simulink

So I have a control system in simulink which I have put into a test harness and I want to find the response time for that system to a step function. So I made a subsystem that returns a 1 when the demand and output systems are within 1% of each other and want to be able to extract a response time by taking the time taken for the 1 to appear away from the time at which the step function switches on but I'm stuck on how to do this. Any ideas?

[TAB]

I am sorry but I didn't got your question. Can you elaborate with more details ?

[Oliver McEnteggart]

Basically I have a graph that goes from 0 to 1 like a step function, and I want to know when it goes to 1 i.e. be able to send that data to a simulink block

[TAB]

You can use Compare block to check when data is moved to 1. Is it not OK for you ?

[Oliver McEnteggart]

That's what I have used but how to I get the value of t when it moves to 1 from that?

Answer 1

[TAB]

Ok, I think you need Sources\Clock block.

It gives the simulation time. You can capture the time output of this block when your comparision satisfied.

-----OR-----

You can log the your data to workspace using To Workspace block selecting format as structure with time. Thus data will be saved in structure format at each time step.After simulation, using matlab commands you can find when the data reached to 1.

[Oliver McEnteggart]

Thank you.

[K E]

I second the suggestion of post-processing in Matlab. You could check your calculation with plots etc.