What is speed of response of a control system

[MattH150197]

Homework Statement

In a report I am asked to assess the speed of response of various systems, however I am not exactly sure what this means, be great if someone could explain

The Attempt at a Solution

Step response plots were produced for each simulation and MATLAB was used to assign characteristics such as settling time and overshoot so is speed of response a combination of these or is it literally how quickly it responds to overshooting or undershooting the final value.

 

[anorlunda]

Speed of response is not a well defined term.

In your attempt at solution, you calculated the response of one system. Where are the various systems?

Do you have the actual written assignment? If so, please post it so that we can see the exact wording.

 

[MattH150197]

Okay i have attached the lab assignment and you will see what I am talking about if you look at the last slide, i have also attached 2 of the different step responses which were for task 2 on the assignment. Thanks.

 

[anorlunda]

OK, it says.

Assess the stability, relative stability, and speed of response of each closed loop system,

It appears that "each closed loop system" refers to the different tuning methods.

The terms "stability, relative stability, and speed of response" have no precise standard definitions. Before we say how we would define them, tell us how you would define them and what measurements you would use to characterize them.

 

[MattH150197]

So we also produced Nyquist and Bode plots for each simulation, for stability i mentioned how there is no encirclement of -1 therefore the system is stable, for relative stability i explained the degree of stability for each system by analysing the phase and gain margin.

 

[CWatters]

I'm very rusty but one way to measure response time is to apply a step input and measure the time it takes for the output to settle within a certain percentage of the expected output.

Perhaps Google Critical damping.

 

[FactChecker]

one way to measure response time is to apply a step input and measure the time it takes for the output to settle within a certain percentage of the expected output.

Without further information, that is also how I would interpret the term "speed of response". The settling time shown in the step response figure is good.

EDIT: I didn't mean to imply that the settling time in the figure is a good settling time. I mean that the type of analysis was probably what the want.

 

[MattH150197]

Okay thanks very much for your help guys!