POV you're in the most challenging stage of your academic career. Good luck
@pranjalsachan1179
Жыл бұрын
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.
@alexpatterson5954
4 жыл бұрын
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
@BrianBDouglas
12 жыл бұрын
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.
@afdelgado1
7 жыл бұрын
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
@TY-un4no
Жыл бұрын
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!
@johnsalvadoresabio2491
5 жыл бұрын
The quality of your videos speak to how much time and effort you put into your channel. Thank you so much.
@Poiarn
10 жыл бұрын
I've never seen or read anything that comes even remotely close to how good this video explains bode plots! Really good job!!
@muratmillidere
10 жыл бұрын
Brian,you are just perfect. Everyone who is interested in control system should watch these videos.
@vargil777
5 жыл бұрын
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.
@jeanapp_
7 жыл бұрын
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)
@Abayas.
5 жыл бұрын
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.
@RC_Engineering
10 жыл бұрын
You may be the best in the world at explaining these concepts. At least for my style of learning.
@grace9465
10 жыл бұрын
agree
@RC_Engineering
10 жыл бұрын
Brian Douglas My whole control systems class at UCSD thanks you
@TheSlyProfessor
6 жыл бұрын
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)...
@paulnnamdi4098
5 жыл бұрын
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.
@joannqiongnachen9849
5 жыл бұрын
Agree! I won't be able to survive my control system exam without him
@fabiospinelli4179
11 ай бұрын
wow amazing video in less than 13 minutes you did what my professor failed to do in more than 5 hours of lesson
@WalidIssa
9 жыл бұрын
at 8:31 it is not correct to write the equation in time and s-domain concurrently. Thanks AWSOME
@BrianBDouglas
9 жыл бұрын
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.
@Rockyfish3
9 жыл бұрын
Walid Issa Yep you are correct. H(t) = y(t)/u(t) = 2 + (1/s)
@youmah25
7 жыл бұрын
شكرا
@NikolaosPapadakis
7 жыл бұрын
Isn't it correct to write it as H(s)= Y(s)/U(s) = 2+1/s
@shrinivasiyengar5799
3 жыл бұрын
Can someone mention what is the correct way of writing?
@RanjithSethu_findmehere
7 жыл бұрын
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
@BrianBDouglas
11 жыл бұрын
Hi Matt, 6 db = a gain of 2. To convert between gain and decibels: db = 20*log10(2).
@BrianBDouglas
11 жыл бұрын
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.
@BrianBDouglas
11 жыл бұрын
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.
@DrgonMark
Жыл бұрын
İ was confused last year but got 100 mark! Thanks bro. 😂
@Johnyindo387
8 ай бұрын
Jakun ge ital😊
@BrianBDouglas
12 жыл бұрын
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.
@shanugarg8428
4 жыл бұрын
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.
@AdityaMishra-pp1gw
4 жыл бұрын
@@shanugarg8428 You can easily use Matlab and Simulink to visualize all this concepts.
@ricky-lee7553
8 жыл бұрын
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!!!
@Natester13
7 жыл бұрын
Saw the samething, glad I saw this comment before I complained lol
@nirbhaythacker6662
7 жыл бұрын
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".
@thehomiebearfifa3528
7 жыл бұрын
lol thats what being a student engineer is in a nutshell
@Barneyismyname
6 жыл бұрын
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 :)
@victorwainaina2584
6 жыл бұрын
.......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
@TonyStark-fh3iv
7 жыл бұрын
first of all.. your lectures are awesome. Sir, please upload lectures on state space, advanced control, Robust and Optimal control.
@BrianBDouglas
12 жыл бұрын
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.
@Amine-gz7gq
Жыл бұрын
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.
@angelivangamboa769
6 жыл бұрын
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
@BrianBDouglas
12 жыл бұрын
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.
@rafaelgonzalez872
2 жыл бұрын
I was looking for the answer to just this in the comments and you delivered. Appreciate it!!!!
@patriceamyot4235
11 жыл бұрын
your explanation of the history of decibels is amazing and thorough! Very impressed!
@olaguibel27
11 жыл бұрын
1:25 I understood at first "It doesn't change shit" hahaha, need to stop seeing this tutorials so late at night.
@franciscos.2301
4 жыл бұрын
DUDE same lmao
@AfrahKhan62
4 жыл бұрын
SAME
@princefunwie2229
3 жыл бұрын
same here man
@haythemoldaccount7953
3 жыл бұрын
1:17 **
@taremekedzwamudzokora5373
7 жыл бұрын
thanks Brian you made control so much easier !!
@BrianBDouglas
11 жыл бұрын
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.
@ejminava407
4 жыл бұрын
Thank you for taking the time, this is very clear
@mathias216thor
9 жыл бұрын
01:17 "It doesnt change shit" Haha
@mechatronicsstudent2648
8 жыл бұрын
+Mathias Thor he said "shape"
@mathias216thor
8 жыл бұрын
+Mechatronics Student no shit Sherlock :p
@mfamily3772
7 жыл бұрын
LMFAO It feels like shit tho
@agggg3524
6 жыл бұрын
You presented me powerful insights. Thank you
@BrianBDouglas
12 жыл бұрын
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.
@andyhype2546
4 жыл бұрын
AaaAAaaaaammennn. You are my god Brian Douglas. I will follow your religion and teachings, just how poles follow the root locus.
@rohanpandya7739
8 жыл бұрын
Thank you Brian, you make controls fun!
@drillsargentadog
4 жыл бұрын
quick comment: An LTI system can generally integrate against some kernels too. For instance, 1/(s+1) is definitely LTI and when you regarding this as a tf from u to y you get the integral representation y(t) = int_0^t e^{-(t-w)}u(w)dw Classic integration by parts shows that this also preserves sinusoidal-ness.
@vivekkumar-py6kp
4 жыл бұрын
Nice explanation
@ohmyfly3501
8 жыл бұрын
once our professor asked me why log operation is used to convert power, i replied with it has something to do with human ear response, he trashed me by making fun of me and now 😁 after like 2 ans half years i got confirmation that i was correct 😎
@killyourdarling9699
7 жыл бұрын
like a boss
@mvtrumpetgeek
10 жыл бұрын
So, do you really write that fast or do you voice over a sped up version of your original work...? either way your videos are great. You explain everything thoroughly and make sure all of the little steps are well taught and not skipped over. Some of the professors at Cal Poly Pomona have a habit of skipping small steps and setting up the overall equations and leaving us to figure out the rest. Great work and I appreciate the hard work and dedicated time you put into the videos!
@sonofrobin73
2 жыл бұрын
This shit has me regretting ever starting engineering school. Puts me to sleep immediately.
@paulart119
3 жыл бұрын
Brillant! BTW, graphics are great - the sketch of Dr.Bell but it distracts from your narrative, just splashing it on the screen instead of the draw presentation would be better I think.
@sealedwings6788
4 жыл бұрын
You are an incredible teacher, incredible. I just leave a question and see if I'm lucky: in this video you put a diagram block system (the first one) expressed in the time domain. One branch multiplies x2 and the other integrates. Then you write how this system treats the input signal sin(0.5*t), and you say it multiplies it by 2 and the other integrates it. Makes a lot of sense, but I just can't find the correct logic connection of this with the fact that the interaction of the input with the system (e.g. a subsystem y=h(x) where h(x) = 2x) is a convolution. Should not the branches of x2 and integration perform a convolution operation with the entering sin(0.5*t)? Thank you infinitely for your response, I hope I explained myself! :)
@asseilalhlafi128
2 жыл бұрын
YOUR VIDEOS ARE BEST
@olivermechling7975
Жыл бұрын
such a great video thanks for making this series Brian :)
@qwerty-mz8is
10 жыл бұрын
at 8:39 why are we using u(t) and y(t) when we are in the frequency domain given laplace. shouldent they be U(S) and Y(S) ?
@youmah25
10 жыл бұрын
it was a mistake it should be U(S) and Y(S)
@JP-vg8vl
4 жыл бұрын
@@youmah25 thanks
@JordanEdmundsEECS
6 жыл бұрын
At 4:30 I feel you didn’t hit home the meaning behind that trig identity. It is in fact more general and can be stated in words: any shifted sine and shifted cosine of arbitrary phase and arbitrary amplitude can be combined into a single sine wave. In other words, you can combine ANY number of sine and cosine terms with any phase and any amplitude into a single term. That’s why this all works, and it just blows me away.
@JordanEdmundsEECS
6 жыл бұрын
Awesome video by the way.
@eamonhannon1103
2 жыл бұрын
Brilliant video ! So well explained !
@jackpekin
6 жыл бұрын
I feel like my uni lecturer should have made us watch this video before going into bode plots. We went straight to transfer functions and then bode plots without learning the reasoning/theory behind it
@someonelikeRika
7 жыл бұрын
Hi, where you've written your trig identity, and you say that "a" must be "greater than or equal to zero" I think you might be mistaken - you can't have a solution to arctan(b/0), with a zero denominator. Regardless of this, thank you so much for your videos! Super helpful and very well presented. Thank you.
@TheJq32
10 жыл бұрын
At 9:20, the transfer function becomes = 2 + 1/w * j . How did j get into the numerator? Shouldn't the transfer function = 2 + 1/s, where s = jw, so the transfer function = 2 + 1/jw?
@myband
9 жыл бұрын
multiply by (-jw/-jw) which is essentially multiplying by 1. it should be 2-1/w*j which he did rectify
9:06 - you say that we look at steady state response ie when sigma = 0. How does sigma = 0 translate to steady state response??
@SohilShah_Melodyman
6 жыл бұрын
Very well explained........thanks!
@christonfredrick
7 ай бұрын
6:09 You're a good artist
@RocketHank
4 жыл бұрын
Thanks for your lecture!! It really helps!! :D
@amberelferink
3 жыл бұрын
I am having trouble with the laplace transform of the control loop you do. You say 2 stays the same, but if I do the maths I get 2/s (also see this from Kahn academy I worked along with: www.khanacademy.org/math/differential-equations/laplace-transform/laplace-transform-tutorial/v/laplace-transform-1), and also find other sources that a laplace transform of a constant becomes c/s. I am quite new to control systems, so this might be stupid, but I really want to understand.
@BrianBDouglas
11 жыл бұрын
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.
@jovanasavic4357
9 жыл бұрын
You've saved my lazy ass once again. Thank you for this amazing lectures!
@BrianBDouglas
12 жыл бұрын
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.
@joulesinwatt
12 жыл бұрын
Thank you again.
@BrianBDouglas
12 жыл бұрын
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.
@null1270
8 жыл бұрын
Is it a pre-requisite of using Bode to check for stability first? Because the transient aka exponential term will only die out if system is stable and not when marginally stable or unstable.
@RUBENKI-cv8cq
Жыл бұрын
From Ecatepec, edo. Mex. Thank you for your explanation. The concept will be better understood.
@BrianBDouglas
11 жыл бұрын
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.
@subinnair3835
5 жыл бұрын
Is the system shown unstable ??...because the pole is on the right side of the imaginary plane ??
@julie_atz
2 жыл бұрын
Love your videos, they are always super insightful! One remark though: When expanding the a sinx +b cosx identity, isn't the phase shift ρ supposed to be atan(a/b)?
@abdulrahmanallam977
6 жыл бұрын
@ 9:55 how did you calculate the imaginary part to be -2 when frequency = 1/2
@EshikaGupta-kd1tl
3 ай бұрын
Why did you define transfer function with the your input and output functions in time domain? Are they not supposed to be in frequency domain?
@globalko
4 жыл бұрын
So the value that we plot in real and imaginary axis is the same plot we get when determining the stable poles?
@drewpierpont3361
5 жыл бұрын
Wow, thank you so much Brian!!
@rjbeatz
3 жыл бұрын
My professor teaches in french which I don't know very well, his method is also shit. Thanks for making me understand it. Not many teachers explain like you
@naut_nigel
5 жыл бұрын
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!!
@jacobhardy2313
2 жыл бұрын
Taught me what my vibrations/control professor couldn’t in a whole semester. Thank you
@MexterO123
9 жыл бұрын
I've never seen that Trig Identity in all of high school @ 3:17 What is that trig identity called. I have a table of trig identities but it's not there. Also is alright for me to think that amplitude is the same as gain because if you were to plot it directly you would be plotting amplitude vs frequency.
@RandomMusingsOfLowMelanin
6 жыл бұрын
Gain is the (amplitude of output) / (amplitude of input), here it is same as the input amplitude is one.
@StupidBadyXD
5 жыл бұрын
why is omega = 1/2? where did that come from?
@azscott8737
8 жыл бұрын
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
@raghuramsatish5995
8 жыл бұрын
you sir deserve a medal Mr.Brian Douglas
@Ryan-jl5yn
5 ай бұрын
bro you absolutely smashed this course! I'm probably not going to my signals class ever again
@FarhanKhan-oz2jb
5 жыл бұрын
THANK YOU SO MUCH
@Amine-gz7gq
Жыл бұрын
At 8:15 why did you use a block with 1/s ??? the inverse laplace of 1/s is 1.
@suharsh96
7 жыл бұрын
I am confused. Why would the gain change with the change in frequency? Gain is just amplitude in logarithmic form right? Why would it change with frequency at @7:53
@BrianBDouglas
7 жыл бұрын
Gain is the change in amplitude as a signal goes through the system. Since all signals can be constructed as sines and cosines we'll just look at a single sine wave as an example. If the input signal is sin(w*t) and the system is an integrator, then the output signal is the integral of sin(w*t)dt. This is -(1/w) * cos(w*t). The change in amplitude between the input and output is 1/w. The negative sign contributes to the phase shift since it just flips the signal upside down without changing the amplitude. So the gain is 1/w which clearly changes as you change the w (or the radians per second of the input signal). I hope this answers your question.
@suharsh96
7 жыл бұрын
Brian Douglas Yes it does. Thank you very much!:)
@subodhss
10 жыл бұрын
This is a great lecture series! Can you please do some lectures on "Controlability" and "Observability" aspects of control theory and it implications for real life systems with some illustrative example. Thanks!
@chuanglu9162
7 жыл бұрын
I have a question here. The Laplace transform of 2, is not 2. Tt is actually 2/S. But when you did it at 2, the answer is still correct, why?
@skybayc
6 жыл бұрын
I'm sure you've long forgotten this question, but in case someone else has the same one I'll respond. 2/S is the transform of 2 times the step function, usually given as u(t). 2 is a constant multiplier here, so by the properties of Laplace transforms can be pulled out. He did not change his function variables in the video, but u(t) in there was the transform of the input, not necessarily the step. That is why he got two times the transform of the input.
@RaedMohsen
12 жыл бұрын
I hope to find lectures on Compensator design....
@yakirwaynberg6497
9 жыл бұрын
great lecture! thank you
@salim786dua
11 жыл бұрын
Sir, you have written y(t)=2u(t)+u(t)/s is the above eqn. correct, cause you have multiplied u(t) with 1/s(integrator) I think it should be either : Y(s)=2U(s)+U(s)/s or y(t)=2u(t)+y(t)*i(t) -- where i(t) is impulse response of integrator please reply
@ahxishwe5664
Жыл бұрын
Just realized i had subscribed 10 years back. And i still need to watch your video today. ❤
@TheGiota100
8 жыл бұрын
Very helpful! Thanks! Studying two days before exams these things ain't easy and your video really did help!
@bsaxon715
10 жыл бұрын
Do you actually write that fast? bloody hell
@tartilasahid8056
5 жыл бұрын
i think hes writing it at normal speed, then edit it using premiere combining with voice over
@Jarrod_C
3 жыл бұрын
Is this lecture series appropriate for beginners?
@BrianBDouglas
12 жыл бұрын
Hi Bill, I will be uploading 4 new videos by the end of the weekend but they will all be on very specific concepts in drawing Bode plots by hand. I wish I had the time to make more of these but I'm normally limited to just one a week. Best of luck on the PE!
@vikasgupta-hl9sq
4 жыл бұрын
You are legend
@hairynutsack9704
6 жыл бұрын
Can anyone explain how the ratio of input to output in time domain is equal to the transfer function in frequency domain. So at 8:58 shouldn't it be Y(s)/U(s) = (2s+1)/2 ?
@droxid666
6 жыл бұрын
Y(s) = 2U(s) + (1/s)*U(s) Y(s) = (2+(1/s))*U(s) Using the comon denominator s, and puting U(s) on the other side, then: Y(s)/U(s) = (2s+1)/s
@dajaq.6497
3 жыл бұрын
Thanks for the high quality video! Why is that 2 - 1/w j at 9:39?
@aly0823
6 ай бұрын
The previous step was 1/jw. If you multiply the numerator and denominator by j, you would end up with j in the nominator and j^2w in the denominator. j^2 is -1, and this is why you end up with -j/w or -1/w j
@sarahwhiteside6196
11 жыл бұрын
You. Are. Amazing.
@Geddiz
5 жыл бұрын
Mate your videos have just about saved my EEE degree, thank you so much for uploading these.
@tomylim6022
10 жыл бұрын
holy cow!!! the drawing is good too...this guy is multi-talent :D
@furetosan
Жыл бұрын
I understand we dont have youtube annotations anymore, but you should remove the a=0 from the denominator at 3:32
@rewindjump1683
8 жыл бұрын
Good lesson dude, I'm a big fan of Bode :D and frog and bode -.- the wheels on the bus go irk n bode irk n bod eirk n bode
Пікірлер: 502