This is amazing! My signals professor doesn't teach very well and now that we've switched to remote learning, he doesn't give us any lectures and only gives us written handouts that are sometimes hard to understand. I love how succinct yet in depth your videos are! You have no clue how much this helps
This is the best playlist out there for understanding bode plots. Believe me, I am an Electrical Engineer and have studied bode plots a number of times but never had such an understanding.
I am funnily also at UCSD, albeit studying computer music. I finally understand why LTI's matter. They don't seem so arbitrary anymore. Now to finish watching all your other videos (which brought me here)...
I paused the video around 9:40 then spent 10 minutes trying to figure out how to get 2+(1/w)j when i kept getting 2-(1/w)j. in the end i gave up and decided to watch the rest of the video anyway only to find you corrected it as a mistake 10 seconds later at 9:50 -_-... That said, your style of videos are absolutely brilliant!!!... so ill let you off this one time =] Cheers!!!
I was doing the same thing, thank god for you that i didn't waste half an hour rummaging through textbooks and google thinking "there must be some other reason as to why he did that, something more complicated".
.......I'm a 3rd year engineering student and it took me 10min to figure out why you were all getting that solution....Don't worry though because I'm trying my hardest to get away from this course. Better 3years late than never, haha
Hello Samay, You are absolutely correct. I should have written the equation in the S-domain completely, or Y(s)=2U(s)+U(s)/s. However, I accidentally left the input and output in the time domain. Thanks for pointing this out. I hope this doesn't confuse anyone watching the video.
The things I learned in these video are way more valuable than the ones I learned over two semesters of control courses. This guy tells you every thing why they are there and where they came from and so on. I wish if I had him as a control professor
I replayed the section explaining the history of decibel unit many times because I was easily distracted by your skilled drawings haha. Thank you for creating clear and fun educational videos!
I'll try to explain it beyond just "The math says so!" :) Look at the equation around 8:30, the input u(t) is affected through two different paths to produce the output. As frequency increases to infinity the 1/s (or integral path) get's closer and closer to zero. You can imagine looking at a really high frequency sine wave and integrating the signal over time. Once the frequency become infinite essentially the area above and the area below the center line both go to zero.
Oh Mr Douglas, you're just awesome. I just couldn't connects these different topics from Fourier and Laplace to s-plane and what's bode plot... I just love the way you teach all these so simply. I would really appreciate if you suggest me something to feel these things deeply to think and analyse. As a would be engineer, I don't want this awesome subject to go apart of me after I know how awesome it is. No doubt your lectures are end to end to grasp the concept but ultimately practice and self exploration is the key. And you understand the things I should go through as only engineer can understand and find an engineer inside a student. Professors just teach for exams and I'm not in face of marks. I'll end my words with the request to reply to this and help me with suggesting resources.
Absolutely! I'm finishing with Bode this week and then want to provide a good practical understanding of stability. I'll touch on root locus at the end of the stability portion and as we get into tuning controllers.
damn... I hate learning material without the history behind it. It's so important in my opinion this literally took like 100 page description in the book and broke it down in less than 13 minutes. thanks
At 6:46, 1 dB = 1/10 bell = 1/10 log10(power), so there's a mistake : 1 dB can't be equal to 10 * log10 etc... unless we use the old definition 1 TU = 10*log10(delta power). 1 dB should be changed by LP for example.
Love the fact that you use so many colors in your video. Makes the complete subject much easier to concentrate for me. I'm a person who thinks graphically so the pictures have to be good, colorful, but with only the essential information in order for me to stay interested (which is not an easy task, as I have noticed ;)), but your video makes me feel that I can understand control systems. Thank you so much! (Love the Mr. Bell that you drew btw)
thanks, you are a true legend! the difference between you and my professor's is they teach cause theyre paid and don't care about us, while you are teaching and saving us! you've saved me with control systems!!
I am Korean and studying aerospace mechanical engineering now. I was struggling with these concepts cuz these things were all new and I didnt know what to do ;(. But, god blessed me and I found these videos so that I can rearrange my concepts through all parts of controlling system. Thank you very much for all these super lectures ♥
Yes, obsession is good word! We are obsessed with sinusoids because Fourier analysis tells us that any arbitrary signal can be represented by a series of sinusoids. In that way we can predict how a system will be affected by any input by knowing how each individual sinusoid is affected.
Yes! I have a bad habit of combining domains like that. ;) I'm trying to catch them and add annotations to correct my mistakes. Thanks for pointing this out.
Dear Brian, your efforts are much appreciated. You made the understanding of control systems very easy, you are the best in making us to visualize the concepts in a deeper sense, your way of presenting is so good that any non-technical person also can understand it. I request you to make a video on how to analyze and understand control concepts using Nichols charts. Thank you.
About your second question. 1/j = -j; Therefore, 2 + 1/(jw) = 2-(1/w)j. When you are plotting on a real/imaginary plot you need to manipulate the value to be in the form real + imag * j, where j is in the numerator. Hope that helps. If you have more questions please leave another comment.
I wish I discovered you back when I took digital signal processing. I learned how to "go through the motions" in that class well enough to pass but without actually understanding anything I was doing. Thank you so much!!!
j = sqrt(-1) so the problem in 1/sqrt(-1). To get the sqrt(-1) in the numerator you have to multiply sqrt(-1)/sqrt(-1). That leaves you with sqrt(-1) / sqrt(-1)^2 which just equals sqrt(-1)/-1 or -j.
Hi Stephanie, the diagram at the beginning of the video had an integral in the lower path. When you take the Laplace Transform of an integral you get 1/s. 1/s is the S-domain representation of integration.
Hi Joules, atan2 is a second form of atan (hence the 2). If you wikipedia atan2 it'll give you a good explanation but I'll try to explain quickly. If you use arctan(num/den) then you'll get the same answer whether num = 1, and den = -1, or if the num=-1 and den=1. These two points are diametrically opposite of each other though and so if you care about which quadrant you're in you need to keep track of the sign of each the num and the den. atan2 keeps track of the sign for you.
Thanx man. Really helpfull. My prof. went really fast over these and I think that was pitty because these are really interresting stuff. So thanx a lot. And a happy new year to all of you.
Love your videos. you "learned" me this material in a night when my professor took 10 weeks confusing me...Thanks for the videos! keep up the good work
Could you add more videos soon. I'm taking my PE (electronics) next week. You're one of the best instructors on you tube; just SLOW down a little. thanks,
Steady state means once the transient response has faded away and all you're left with is the response as time approaches infinity. So if you input a sine wave into your system, and you wait for all of the transients to die away, and then you measure the resulting sine wave amplitude and phase out, you'll have your steady state response. And this is the response that the Bode plot is concerned with. Please let me know if that didn't clear it up for you.
sir, in the beginning of video you said about sine wave and linearity , it was thought provoking i say. Now i got a new way of differentiating linear element and non linear element in circuit components , thanku
Since at infinite frequency the 1/s path goes to zero then the output is just equal to 2 times the input since that's the only path left. That is where the gain of 2 comes from at infinite frequency. As for 6 dB, to convert from amplitude gain to dB you use 20*log10(gain). log10(2) is approximately 0.3 and 20 times that is 6 dB.
Golaharsh, thanks for the comment. If you go to my channel I've created a playlist of my videos in sequential order. If you click on the playlist you can find all of the videos that follow this one.
I'm an italian automation engineer student and I found you channel yesterday!.. the way you explain is awesome both for recap and for studying because although you don't use many math (in italy there are great control teachers but the extreme formalization is often misleading) you (incredibly) don't lack in (big) loss of generality..are you going to make videos about state space control schemes and system theory in general? it would be great! Thank you for everything!!
Hi Albert, I believe I said it correctly. 1 bel = 10 decibels, since it takes 10 decibels to make up one bel. Therefore, in order to go from bels to decibels you need to multiply by ten. 3 bels = 3 * 10 decibels.
Firstly EXCELLENT video! Using so much geometry (i.e. a lot of illustrations, plots, diagrams etc) is incredbly helpful in order to understand how things are related. At my university unfortunately the convention is rather to just say "here's a task, calculate it by using the formula". When you ask "but why do you do it like that, why does it work?" the answer is often "That doesn't matter, just use the formula." Well it DOES matter if you want to understand the subject, and your videos help in doing just that. SO KEEP UP THE GOOD WORK! For this video I just have a question. You say the sine wave input will always have a sine wave output, and the only thing that will change is the amplitude, not the shape. Why can't the output change frequency? What about for example an oscillator? Because there you can regulate the frequency. Is an oscillator not an LTI system then?
Thank You very much Brian Douglas, this is a GREAT video. Very well spoken, elaborate, and visually helpful with your color changes. I only wish you would have answered the question which so many people asked, which was why the laplace transform of 2 for the multiplier wasn't 2/s. One person attempted to answer this, but I didn't understand it completely after around 30 -40 minutes of painstaking rummaging thu the internet and literature. But thank you so very much, this video greatly helped.
Man, you are perfect ON THESE VIDEOS!! I was thinking to ask you, if it possible from you...please make some new videos for the Nyquist plot. You have a perfect method of explaining intuitively the concept of frequency response. Suxes!!
supplementing Brian's answer: read below, I have a system who responds like this: e^(-4t)+sin(10t) now observe that e^-4t term dies out in first as t increases but sin10t stays as it is. So, sin10t is Steady State response and we are interested in that steady state response when we wish to use Bodes
This is amazing! My signals professor doesn't teach very well and now that we've switched to remote learning, he doesn't give us any lectures and only gives us written handouts that are sometimes hard to understand. I love how succinct yet in depth your videos are! You have no clue how much this helps
This is the best playlist out there for understanding bode plots. Believe me, I am an Electrical Engineer and have studied bode plots a number of times but never had such an understanding.
You may be the best in the world at explaining these concepts. At least for my style of learning.
agree
Brian Douglas My whole control systems class at UCSD thanks you
I am funnily also at UCSD, albeit studying computer music. I finally understand why LTI's matter. They don't seem so arbitrary anymore. Now to finish watching all your other videos (which brought me here)...
Exactly the same with me. The way he exlains it is best I have come across ever. Wonder why a lot of other teachers do it the way they do.
Agree! I won't be able to survive my control system exam without him
I paused the video around 9:40 then spent 10 minutes trying to figure out how to get 2+(1/w)j when i kept getting 2-(1/w)j. in the end i gave up and decided to watch the rest of the video anyway only to find you corrected it as a mistake 10 seconds later at 9:50 -_-...
That said, your style of videos are absolutely brilliant!!!... so ill let you off this one time =]
Cheers!!!
Saw the samething, glad I saw this comment before I complained lol
I was doing the same thing, thank god for you that i didn't waste half an hour rummaging through textbooks and google thinking "there must be some other reason as to why he did that, something more complicated".
lol thats what being a student engineer is in a nutshell
Haha i saw it too so I went to the comments instead to see if someone pointed it out, your comment saved me from spending 10 minutes as well :)
.......I'm a 3rd year engineering student and it took me 10min to figure out why you were all getting that solution....Don't worry though because I'm trying my hardest to get away from this course. Better 3years late than never, haha
Hello Samay, You are absolutely correct. I should have written the equation in the S-domain completely, or Y(s)=2U(s)+U(s)/s. However, I accidentally left the input and output in the time domain. Thanks for pointing this out. I hope this doesn't confuse anyone watching the video.
İ was confused last year but got 100 mark! Thanks bro. 😂
Jakun ge ital😊
POV you're in the most challenging stage of your academic career. Good luck
The things I learned in these video are way more valuable than the ones I learned over two semesters of control courses. This guy tells you every thing why they are there and where they came from and so on. I wish if I had him as a control professor
your explanation of the history of decibels is amazing and thorough! Very impressed!
The quality of your videos speak to how much time and effort you put into your channel. Thank you so much.
I replayed the section explaining the history of decibel unit many times because I was easily distracted by your skilled drawings haha. Thank you for creating clear and fun educational videos!
I've never seen or read anything that comes even remotely close to how good this video explains bode plots!
Really good job!!
I can't believe it took me 2 years after graduating when I'm at a professional job to find these hidden gems of videos! Thank you!!
Since 2012 (10 Years) this is the best Video about Bode Plots
I'll try to explain it beyond just "The math says so!" :) Look at the equation around 8:30, the input u(t) is affected through two different paths to produce the output. As frequency increases to infinity the 1/s (or integral path) get's closer and closer to zero. You can imagine looking at a really high frequency sine wave and integrating the signal over time. Once the frequency become infinite essentially the area above and the area below the center line both go to zero.
Oh Mr Douglas, you're just awesome. I just couldn't connects these different topics from Fourier and Laplace to s-plane and what's bode plot... I just love the way you teach all these so simply. I would really appreciate if you suggest me something to feel these things deeply to think and analyse. As a would be engineer, I don't want this awesome subject to go apart of me after I know how awesome it is. No doubt your lectures are end to end to grasp the concept but ultimately practice and self exploration is the key. And you understand the things I should go through as only engineer can understand and find an engineer inside a student. Professors just teach for exams and I'm not in face of marks. I'll end my words with the request to reply to this and help me with suggesting resources.
@@shanugarg8428 You can easily use Matlab and Simulink to visualize all this concepts.
Absolutely! I'm finishing with Bode this week and then want to provide a good practical understanding of stability. I'll touch on root locus at the end of the stability portion and as we get into tuning controllers.
"Your explanation of control systems is amazing. You absolutely nailed it, my friend."
Taught me what my vibrations/control professor couldn’t in a whole semester. Thank you
I have to say this, you are the greatest control teacher I have ever seen
Just realized i had subscribed 10 years back. And i still need to watch your video today. ❤
Brian,you are just perfect. Everyone who is interested in control system should watch these videos.
damn... I hate learning material without the history behind it. It's so important in my opinion this literally took like 100 page description in the book and broke it down in less than 13 minutes. thanks
These lectures are so helpful, I wouldn't be passing with control theory module without them.
This was an amazing video. I was shocked to see it is over 10 years old at this point, unreal quality!
At 6:46, 1 dB = 1/10 bell = 1/10 log10(power), so there's a mistake : 1 dB can't be equal to 10 * log10 etc... unless we use the old definition 1 TU = 10*log10(delta power). 1 dB should be changed by LP for example.
Love the fact that you use so many colors in your video. Makes the complete subject much easier to concentrate for me. I'm a person who thinks graphically so the pictures have to be good, colorful, but with only the essential information in order for me to stay interested (which is not an easy task, as I have noticed ;)), but your video makes me feel that I can understand control systems. Thank you so much!
(Love the Mr. Bell that you drew btw)
Mate your videos have just about saved my EEE degree, thank you so much for uploading these.
thanks, you are a true legend! the difference between you and my professor's is they teach cause theyre paid and don't care about us, while you are teaching and saving us! you've saved me with control systems!!
I am Korean and studying aerospace mechanical engineering now. I was struggling with these concepts cuz these things were all new and I didnt know what to do ;(. But, god blessed me and I found these videos so that I can rearrange my concepts through all parts of controlling system. Thank you very much for all these super lectures ♥
Excellent explanation. I don't even know English so good, but i've understood almost 100% of the content. Thanks!
bro you absolutely smashed this course! I'm probably not going to my signals class ever again
you sir deserve a medal Mr.Brian Douglas
I know my professor means well, but boy oh boy do your explanations blow his out of the water! Thank you for putting this up.
I love how everything somehow starts to make sense after you explain it. Thanks so much for taking the time out to make these videos!
Yes, obsession is good word! We are obsessed with sinusoids because Fourier analysis tells us that any arbitrary signal can be represented by a series of sinusoids. In that way we can predict how a system will be affected by any input by knowing how each individual sinusoid is affected.
EE student on senior year. Super appreciate this intuitive outlook on bode plots.
at 8:31 it is not correct to write the equation in time and s-domain concurrently. Thanks AWSOME
Yes! I have a bad habit of combining domains like that. ;) I'm trying to catch them and add annotations to correct my mistakes. Thanks for pointing this out.
Walid Issa Yep you are correct. H(t) = y(t)/u(t) = 2 + (1/s)
شكرا
Isn't it correct to write it as H(s)= Y(s)/U(s) = 2+1/s
Can someone mention what is the correct way of writing?
Dear Brian, your efforts are much appreciated. You made the understanding of control systems very easy, you are the best in making us to visualize the concepts in a deeper sense, your way of presenting is so good that any non-technical person also can understand it. I request you to make a video on how to analyze and understand control concepts using Nichols charts. Thank you.
This just saved my butt for my control systems homework! You are so much better than my actual professor! Thank you!
Very helpful! Thanks! Studying two days before exams these things ain't easy and your video really did help!
About your second question. 1/j = -j; Therefore, 2 + 1/(jw) = 2-(1/w)j. When you are plotting on a real/imaginary plot you need to manipulate the value to be in the form real + imag * j, where j is in the numerator. Hope that helps. If you have more questions please leave another comment.
you explain these concepts much better than my professor can in an hour and a half
Exactly, I don't know why I am paying ton of money to university :| after all youtube is what helping me.
I wish I discovered you back when I took digital signal processing. I learned how to "go through the motions" in that class well enough to pass but without actually understanding anything I was doing. Thank you so much!!!
this is what im waiting to watch on youtube , very good job Professor
One of the best youtube lectures I've seen. Thank You.
wow amazing video in less than 13 minutes you did what my professor failed to do in more than 5 hours of lesson
Thank you so much for these videos. I'm recommending them to all my friends. A million times better than the textbook we have!
j = sqrt(-1) so the problem in 1/sqrt(-1). To get the sqrt(-1) in the numerator you have to multiply sqrt(-1)/sqrt(-1).
That leaves you with sqrt(-1) / sqrt(-1)^2 which just equals sqrt(-1)/-1 or -j.
I was looking for the answer to just this in the comments and you delivered. Appreciate it!!!!
Hi Stephanie, the diagram at the beginning of the video had an integral in the lower path. When you take the Laplace Transform of an integral you get 1/s. 1/s is the S-domain representation of integration.
well, i dont know how to thank you brian but i can say you are the best, indeed you are thank you
This led me to enlightenment in control engineering.Great lecture and let's make this lectures to be known for content seekers by sharing 👏
Great class! You are the best teacher that I have seen!
Hi Joules, atan2 is a second form of atan (hence the 2). If you wikipedia atan2 it'll give you a good explanation but I'll try to explain quickly. If you use arctan(num/den) then you'll get the same answer whether num = 1, and den = -1, or if the num=-1 and den=1. These two points are diametrically opposite of each other though and so if you care about which quadrant you're in you need to keep track of the sign of each the num and the den. atan2 keeps track of the sign for you.
I've been suffering trying to understand these concepts but now you have just solved my problem ,thanks a lot
Such an amazing lecture series, so few comments. Extremely underrated (most of educational resources at UA-cam feel this way).
Great descriptions mate, appreciate your videos making simple explanations on quite a difficult topic.
Love the lectures! You're changing the world. Legit. Bringing quality education to the masses. Thank you!
You've saved my lazy ass once again. Thank you for this amazing lectures!
From Ecatepec, edo. Mex. Thank you for your explanation. The concept will be better understood.
thanks brian, m learning bode this time... and thanks to you!! hats off - you are doing a good job educating people around the globe :)
Thanx man. Really helpfull.
My prof. went really fast over these and I think that was pitty because these are really interresting stuff. So thanx a lot. And a happy new year to all of you.
Love your videos. you "learned" me this material in a night when my professor took 10 weeks confusing me...Thanks for the videos! keep up the good work
this video was soooooooooooooooooooo useful, I understood so many concepts, the introduction really helped
That was an amazing lecture. I would pay money for a full course in feedback by you, not even kidding.
Excellent explanation, brought me back to school of what I remembered about this work...
8 years later still helping me. Thanks
You are really awesome... You just connected my neurons together to understand bode plot.... You are great...
Could you add more videos soon. I'm taking my PE (electronics) next week. You're one of the best instructors on you tube; just SLOW down a little. thanks,
Excellent video with all basic concepts revised for explanation.
Missed my courses lecture on bode diagrams, this is a life saver! Thanks!
Awesome video as usual and that sketch was awesome!
Steady state means once the transient response has faded away and all you're left with is the response as time approaches infinity. So if you input a sine wave into your system, and you wait for all of the transients to die away, and then you measure the resulting sine wave amplitude and phase out, you'll have your steady state response. And this is the response that the Bode plot is concerned with. Please let me know if that didn't clear it up for you.
Hi Matt, 6 db = a gain of 2. To convert between gain and decibels: db = 20*log10(2).
1:25 I understood at first "It doesn't change shit" hahaha, need to stop seeing this tutorials so late at night.
DUDE same lmao
SAME
same here man
1:17 **
sir, in the beginning of video you said about sine wave and linearity , it was thought provoking i say. Now i got a new way of differentiating linear element and non linear element in circuit components , thanku
You are a magnificent teacher.
You are amazing! I learned these ideas at uni, got good grate back then BUT god I had no idea about the concept behind them. Now I understand!
Since at infinite frequency the 1/s path goes to zero then the output is just equal to 2 times the input since that's the only path left. That is where the gain of 2 comes from at infinite frequency. As for 6 dB, to convert from amplitude gain to dB you use 20*log10(gain). log10(2) is approximately 0.3 and 20 times that is 6 dB.
Golaharsh, thanks for the comment. If you go to my channel I've created a playlist of my videos in sequential order. If you click on the playlist you can find all of the videos that follow this one.
I'm an italian automation engineer student and I found you channel yesterday!.. the way you explain is awesome both for recap and for studying because although you don't use many math (in italy there are great control teachers but the extreme formalization is often misleading) you (incredibly) don't lack in (big) loss of generality..are you going to make videos about state space control schemes and system theory in general? it would be great! Thank you for everything!!
holy cow!!! the drawing is good too...this guy is multi-talent :D
This saved me so much time. Amazing explanation!!!
Hi Albert, I believe I said it correctly. 1 bel = 10 decibels, since it takes 10 decibels to make up one bel. Therefore, in order to go from bels to decibels you need to multiply by ten. 3 bels = 3 * 10 decibels.
Excellent tutorial for beginner to understand the basics!!
Man, that was very well explained; another subscriber here. Thanks man!
Sir...you are lecture are awesome sir...you are best teacher in the world... awesome lectures sir...you had made my day better
Firstly EXCELLENT video! Using so much geometry (i.e. a lot of illustrations, plots, diagrams etc) is incredbly helpful in order to understand how things are related. At my university unfortunately the convention is rather to just say "here's a task, calculate it by using the formula". When you ask "but why do you do it like that, why does it work?" the answer is often "That doesn't matter, just use the formula." Well it DOES matter if you want to understand the subject, and your videos help in doing just that. SO KEEP UP THE GOOD WORK!
For this video I just have a question. You say the sine wave input will always have a sine wave output, and the only thing that will change is the amplitude, not the shape. Why can't the output change frequency? What about for example an oscillator? Because there you can regulate the frequency. Is an oscillator not an LTI system then?
Thank You very much Brian Douglas, this is a GREAT video. Very well spoken, elaborate, and visually helpful with your color changes. I only wish you would have answered the question which so many people asked, which was why the laplace transform of 2 for the multiplier wasn't 2/s. One person attempted to answer this, but I didn't understand it completely after around 30 -40 minutes of painstaking rummaging thu the internet and literature. But thank you so very much, this video greatly helped.
Amazing content. I always used to wonder why are we multiplying 20 time log for decibels. Thank you so much.
You're an excellent teacher
Man, you are perfect ON THESE VIDEOS!! I was thinking to ask you, if it possible from you...please make some new videos for the Nyquist plot. You have a perfect method of explaining intuitively the concept of frequency response. Suxes!!
Thank you Brian, you make controls fun!
thanks Brian you made control so much easier !!
Yes you are right ... but I corrected it at 9:55. Good catch!
i love how you draw Alexander Graham Bell's figure!! so cute!!
supplementing Brian's answer: read below,
I have a system who responds like this: e^(-4t)+sin(10t)
now observe that e^-4t term dies out in first as t increases but sin10t stays as it is. So, sin10t is Steady State response and we are interested in that steady state response when we wish to use Bodes
Keep up the excellent work. I majored in control systems and I've forgot a few of these concepts. I
man we need you back dude!!
first of all.. your lectures are awesome.
Sir, please upload lectures on state space, advanced control, Robust and Optimal control.
Thank you for taking the time, this is very clear
I came in with little to no idea of bode plots. I now am pretty good in it.