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RE: How to find the point on the root locus with a certain damping in Octave
May 15, 2023 at 2:28 am
(May 14, 2023 at 5:49 am)FlatAssembler Wrote: So, allegedly, for the gain of 0.723288, the damping is equal to 0.689481 (very close to the required damping of 0.7), and the frequency is 0.104 rad/sec. How do I check whether that's true? As early as my first semesters at university i figured (and was told by my profs) that anyone calculating 6 digit numbers trying to solve a 2 digit number problem has no idea what he is doing.
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RE: How to find the point on the root locus with a certain damping in Octave
May 16, 2023 at 12:43 pm
(May 15, 2023 at 2:28 am)Deesse23 Wrote: (May 14, 2023 at 5:49 am)FlatAssembler Wrote: So, allegedly, for the gain of 0.723288, the damping is equal to 0.689481 (very close to the required damping of 0.7), and the frequency is 0.104 rad/sec. How do I check whether that's true? As early as my first semesters at university i figured (and was told by my profs) that anyone calculating 6 digit numbers trying to solve a 2 digit number problem has no idea what he is doing.
We were also taught that in our high-school chemistry classes. But in our university physics classes, we were taught that real science uses error margins in inputs, and that it claculates the error margins of the results using the partial derivatives of the formulas.
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RE: How to find the point on the root locus with a certain damping in Octave
May 16, 2023 at 1:53 pm
(May 15, 2023 at 2:28 am)Deesse23 Wrote: (May 14, 2023 at 5:49 am)FlatAssembler Wrote: So, allegedly, for the gain of 0.723288, the damping is equal to 0.689481 (very close to the required damping of 0.7), and the frequency is 0.104 rad/sec. How do I check whether that's true? As early as my first semesters at university i figured (and was told by my profs) that anyone calculating 6 digit numbers trying to solve a 2 digit number problem has no idea what he is doing.
I think you might be on to something.
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RE: How to find the point on the root locus with a certain damping in Octave
May 16, 2023 at 2:13 pm
(May 16, 2023 at 1:53 pm)Jackalope Wrote: (May 15, 2023 at 2:28 am)Deesse23 Wrote: As early as my first semesters at university i figured (and was told by my profs) that anyone calculating 6 digit numbers trying to solve a 2 digit number problem has no idea what he is doing.
I think you might be on to something.
Shall i ask him if the damping value he was supposed to look for was rather 0.707 instead of 0.7? What do you think?
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RE: How to find the point on the root locus with a certain damping in Octave
May 17, 2023 at 6:16 am
(This post was last modified: May 17, 2023 at 6:32 am by FlatAssembler.)
I am not certain whether the frequency for some complex root is indeed equal to the absolute value of the imaginary part of that root (as I have programmed into my program) or if it is equal to the absolute value of that root. I think it is equal to the absolute value of the imaginary part, because how can a root that's lying on a real axis (so that damping is equal to one) have a frequency? If the damping is equal to one, then the step response does not resemble a sinusoid, to have some frequency.
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RE: How to find the point on the root locus with a certain damping in Octave
May 17, 2023 at 8:16 am
(May 17, 2023 at 6:16 am)FlatAssembler Wrote: I am not certain whether the frequency for some complex root is indeed equal to the absolute value of the imaginary part of that root (as I have programmed into my program) or if it is equal to the absolute value of that root. I think it is equal to the absolute value of the imaginary part, because how can a root that's lying on a real axis (so that damping is equal to one) have a frequency? If the damping is equal to one, then the step response does not resemble a sinusoid, to have some frequency.
What did i say!?: You dont have an idea what you are doing, but your answer to "please look for 0.7" has six digits.
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RE: How to find the point on the root locus with a certain damping in Octave
May 30, 2023 at 12:24 pm
About a week ago, I had an opportunity to try this out in MatLab at the university, and MatLab prints results by orders of magnitude different from the results that the C++ program I've written prints. MatLab prints that for the damping of 0.701, the gain is 43.9 and the frequency is 0.141 rad/s. It is way more likely I got something wrong in my C++ program (though I'd like to know what) than in MatLab.
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RE: How to find the point on the root locus with a certain damping in Octave
May 30, 2023 at 12:47 pm
@ FlatAssembler
Have you learned nothing from recent events? Nothing at all?
Boru
‘I can’t be having with this.’ - Esmeralda Weatherwax
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RE: How to find the point on the root locus with a certain damping in Octave
May 30, 2023 at 1:19 pm
(May 30, 2023 at 12:47 pm)BrianSoddingBoru4 Wrote: @FlatAssembler
Have you learned nothing from recent events? Nothing at all?
Boru
What recent events?
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RE: How to find the point on the root locus with a certain damping in Octave
May 30, 2023 at 1:27 pm
You obviously learned nothing from your week-long time out. Perhaps you can learn from a longer, if not permanent, break from the forum.
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