Brian Douglas you are a HERO. I am an Engineering student in Belgium, I followed the course Control System Engineering (CSE) in Bachelor and Master year. In the Master I had no idea what the purpose of this course was, I did not understand why the professor was making strange drawings in the S-plane all the time. Then finally I found your video lectures. I have watched your full playlist. You inspired me to like CSE. You understand how the brain wants to study. You explain the purpose of each subject, you make drawings, you use different colours, you talk fast so we can train our brains to think faster, and if it is going to fast we can pause and replay. I really enjoyed your lectures. This will definately make me a better engineer. Yesterday I aced the Exam of Control System Engineering. Thank you very much! I wish you the best in life, and I hope you will continue your purpose to help engineers from all over the world.
Brian Douglas - A man who puts in his time and effort to help electrical engineering students from all around the globe. Not all heroes wear capes, some just explain electrical engineering concepts.
I'm a student from Korea, and your video has truly been a lifesaver for me. I was struggling to understand my professor's lecture, but your explanation made everything clear. Thank you so much, and may you be blessed abundantly!
I'm having control system exam tomorrow and I came to this channel because I didn't attend the classes of the same professor you are referring to here "Prof. Madan Gopal" ...lol
I am also studying engineering and I have a funny story for you Brian. The other day, when finishing the automatics and controls course, the professor said: "If somebody did not understand something I have been explaining this last weeks during hours of lectures, you can search a guy named Brian Douglas in youtube and he will explain it in a few minutes with his videos. Have nice holidays". -- True story. You have reached universities professors! Keep on!! Incredible videos. Lots of information explained clearly and quickly. Thank you for your amazing work!
This video is pure gold. It helped me understand something that my course material couldn't in 25 pages. I finally am getting a grasp on system control! If I pass this exam it is due to your videos, so extremely helpful.
The 3 possibilities: 1.- The -1 does not get circled; the system is stable if there are no poles in the RHP. 2.- The -1 gets circled one or more times in a CCW direction; the system is stable if the # of times it gets circled is equal to the # of poles in the RHP. 3.- The -1 gets circled one or more times in a CW direction; the system is unstable.
great summary ! Sir. I have a question of this video: at 12:11, the gain on the w plane should be undefined, since the magnitude of zero phasor ( no zero for 1/s ) is also 0. According to the definition at 4:18.
To clarify; if a zero (not a pole) is in the RHP the system is unstable, because the Transfer Function we're evaluating is actually the Denominator of the ACTUAL Transfer Function we're determining stability on. (GH is open loop, but X / (1+GH) is close loop). Nyquist difference between GH and 1+GH is just a shift of -1, so we evaluate GH as though its our transfer function, when in reality we're evaluating the Denominator of the transfer function. So what indicates stability, and what indicates instability, is flipped. I.E. a pole creates a denominator of infinity, which is stable, while a zero creates a denominator of zero, which is unstable for the full thing. Just wanted to help make that clear for anyone that missed it.
+Brian Douglas Mister Douglas I wanted to ask that in the last minute you said that there is one pole in the right half plane and two clockwise encirclement's of -1 so there are three poles in the right half plane. But in the previous lecture you said this Z=N+P. That clockwise rotation plus poles is equal to zeros in the right half plane. So which one is it? I am confused.
I believe this formula Z = N + P finds how many open loop (GH) zeros exceeds the open loop poles in the RHP, if the contour is CW. (If the contour was CCW it would be how many open loop poles exceeds the open loop zeros in the RHP of the s-plane). In this case N=2, so we know we have 2 open loop zeros more than poles in the RHP. But since the open loop tranfer function is in the denominator of the closed loop transfer function G/(1+GH), this open loop zeros we found in excess are related to the poles of the closed loop TF. He showed in MATLAB that there is one unstable open loop pole, so in the end of the day the formula says that apart from that 1 unstable open loop pole, we will have more 2 (=N) unstable closed loop poles, so a total of 3. Please comment if I said something wrong...
I love your explanations Brian. You explain the theory but importantly you also put the theory in a context that makes sense to an engineering student. You convey to the viewer the big picture of how the theory is used to solve real world and meaningful problems! Thank you.
Also a mechanical engineer here!! You are really a life saver and an excellent lecturer! it's really helpful for students like me that this subject is just something you should know a little about. You really make it funny! THANKS
The way you explain is awesome. I have been relying on your videos to pass all the quizzes and assignments in present semester. I would be very thankful if you can upload the part 3 of Nyquist Stability Criterion which explains gain and phase margin.... Your efforts are highly appreciated. Thank you :)
Dude (Brian Douglas) do you know how many undergraduate lives you are saving by uploading these amazing videos. You are like Mother Teresa but with balls. I read the book but it takes so long to make sense of it....this is it man this is it!!!
Brian! you are savior... I`m Electrical Engineering student in Pakistan. Our professor for the course 'Feedback and Control Systems' recommended this video in his lecture. I`m totally in love with the way you explained such difficult topics. Keep doing the good work. HATS OFF 🙌🙌🙌
Fantastic lectures about the Nyquist Criterion. I am a student of the Engineering Physics programme at the Royal Institute of Technology in Sweden. Signed up to your channel and will be following your channel. I am doing the undergraduate course of Control Theory right now.
I laughed when I heard you say "if you'd like to hear it from a professional professor", I'm here because my 'professional professor' did a terrible job explaining it and you're actually better. I'm sure Prof Gopal is great but I'll take your simple explainations anyday
thank you so much Brian, you are a perfect teacher, i feel sad that i did not found your videos in the beginning of the semester. wish you the best, you are number one!
You have no idea how much you've helped me this semester! Thank you for the time and the work you put into these videos to help everyone around the world! 🤩🤩
I just want to say that, if I pass my exam tomorrow, it will most definitely be because of you! You explain 10x better than my teacher, thank you so much for putting your time into making these videos! Subscribed ;)
BRILLIANT example.... Thanks so much. Last video left me itching for an explanation on why bode plots don't help with unstable systems. This gave me some insight into that atleast.
Im mechanical engineering (structure and material) student from Malaysia. I really hate this control system because i dont know anything what lecturer teach about ! Then, when i see your lecture on this video, its interesting subject actually !! you are great lecturer ! Thanks sir!!
this video really helped me in understanding nyquist... i really didn't quite get it from the lecture at the university.. but it was really made simple here. thanks a ton~! :)
I love everything about your videos and I can't thank you enough for your help in my control systems course. I have just a small comment on the sound of them howerver: usually I listen to them with headphones, and I've noticed that sometimes the sound is a bit biased towards one ear (usually the right hand one). One example would be the video of stability margin, number 17 in your video. Also the sound level sometimes differ between your videos, which is slightly annoying when going through a playlist. Minor things really, but if you cold make the sound mono and level the sound to a specified level you would really reach perfection. Thanks again!
Awsome lecture series on nyquist plots.... @ 18:19 .i have a doubt, if there are 2 cw encirclements of -1 and one unstable pole... shouldnt we expect 3 unstable zeroes.
yes indeed, you are right One unstable (open-loop) pole is an unstable (closed-loop) zero. It's flipped. Thankfully , @bmoore4313 clarified this things up in the upper comment section.
Hi Brian, Thanks for the videos :) Appreciate it. Can you point me to few other examples where Nyquist plot shows the system is unstable while Bode says it's stable? I am interested in analyzing such systems. Thanks for your time and effort!
Only apropriate thing to say after this great video would be "svaka ti dala" in Croatian (roughly translated: "I hope every woman you meet puts out for you")
Damn you make me feel all my graduate school tuition is in vain! Actually, your demonstration is waaaay better than most professional professors, huge THANX!!
Although I have a Ph.D. in Mechanical Engineering from U of M, I absolutely HATED this topic of control. My concentration is in Manufacturing where I don't really have to deal with controls much. Of course I took required control courses in UG, got A's, but never really understood the true meanings of the topic. Watched your videos.... So clear now. In just 1 hour, it feels like all the puzzles found its places. I really wish my professors taught this course like you did...
Could you make a quick video in witch to explain how to draw s+1 / s^2 +1 or something similar. It is a curious transfer function this one - I know how to draw it and a little bit of why we draw it like we do, but I would love to hear your explanations. By the way, you make the best videos !
Could some one explain why the phase is -90 degree in the s-plane at the time 13:45 and 14:28? I think it should be +90 degree because the points are in the positive part of the imaginary axis.
No, this is done in the right way. Have a look in the previous video. There he explains how the phase in the w-plane happens to be, how it is. The phase of the W-plane phasor depends on the starting point of the Phasor in the S-plane. The phases of phasors starting from poles are substracted from the phases of phasors starting from 0´s. In this case here we just have one single pole, so the positive phase in the S-plane maps negative in the w-plane. Correct me if I'm wrong. Greetings
These videos have been brilliant. Is there a part 3 to the Nyquist series? Gain and phase margins are mentioned as being in the next video - can't find any indication there is a next video.
This is the better explanation I found on the Internet about Nyquist criterion(I viewed also the explanation of the indian professor you suggested). But there’s problem that I’m not able to solve: the only calculations that we do with the transfer function to plot it, is to consider it restricted to s value j-omega from j-zero to j-plus infinity... but: how can we be sure that the Nyquist contour is the one that include the right half plane (and not instead, the left half plane)? If we draw the contour of the left half plane we arrive to the same conclusion about the route from j-zero to j-plus infinity. Do you have the answer to this “tricky” question? Thanks.
Great video. I like your lecture more than my professor. Could you please answer my concern of your video 1/s example? at 12:11, the gain on the w plane should be undefined, since the magnitude of zero phasor ( no zero for 1/s ) is also 0. According to the definition at 4:18.
Great Video!!! One querstion: HOW on earth did you get the TF of the openloop system of the F16??? I would love to read more of the FC system of that plane! Thank you for your work!
Brian, thank you. The explanations in both Part 1 and Part 2 are brilliant. 👍 However, you spoke a bit fast, and I had to pause and replay several times.😅
Hello. Nice lecture. Just wanted to precise something (actually is kind of something i'd like to confirm). I was using matlab to understand what you are explaining. I saw that proper functions do not give a gain of 1, but the gain equals the limit of the function when s goes to infinite e.g. if the function is, as in your video, (s+5)/(2s+3), the nyquist plot passes through the point 1/2 with 0 angle.
z = n + p, where z is zeros of 1+KG(s)H(s) in RHP (i.e. closed loop poles in RHP) n is clockwise encirclements of -1 p is open loop poles in RHP So here you got n=2 and p=1, z=n+p=2+1=3. Three zeros of 1+KG(s)H(s) in RHP, which in other words is 3 closed loop poles in RHP
@@tsunghan_yu how open loop zeros in rhp becomes closed loop poles in rhp? OL tf= G(S)=G(n)/G(d) so open loop zeros we get by putting G(n)=0.......(A) CL tf=G(s)/(1+G(s)) i.e. G(n)/(G(n)+G(d)) its closed loop poles we get by putting G(n)+G(d)=0.......(B) both eqn(A) and (B) are different. pls reply if i am wrong
Hello, Mr Brian! I studied Control Theory Systems in Leningrad (now St Peterburg) in 1991, but not completed, because of marriage and moved to Ukraine. Thank you very much!
Brian Douglas you are a HERO.
I am an Engineering student in Belgium, I followed the course Control System Engineering (CSE) in Bachelor and Master year. In the Master I had no idea what the purpose of this course was, I did not understand why the professor was making strange drawings in the S-plane all the time.
Then finally I found your video lectures. I have watched your full playlist.
You inspired me to like CSE. You understand how the brain wants to study. You explain the purpose of each subject, you make drawings, you use different colours, you talk fast so we can train our brains to think faster, and if it is going to fast we can pause and replay.
I really enjoyed your lectures. This will definately make me a better engineer.
Yesterday I aced the Exam of Control System Engineering.
Thank you very much!
I wish you the best in life, and I hope you will continue your purpose to help engineers from all over the world.
Hehe, second bachelor year engineer here, in exactly the same situation. You went to Leuven?
x3 here! Leuven salutes you Brian
It's good but speaking so fast! These topics are new for me so subtitles (not a native speaker) and pauses are helping me :)
As a mech student, i constantly think to myself, what would i do without you mr. douglas
us mech students owe you big time man
Brian Douglas - A man who puts in his time and effort to help electrical engineering students from all around the globe. Not all heroes wear capes, some just explain electrical engineering concepts.
Also Mechanical engineering! 😄
I'm a student from Korea, and your video has truly been a lifesaver for me. I was struggling to understand my professor's lecture, but your explanation made everything clear. Thank you so much, and may you be blessed abundantly!
I'm having control system exam tomorrow and I came to this channel because I didn't attend the classes of the same professor you are referring to here "Prof. Madan Gopal" ...lol
You're lucky then. Are you in SNU?
I had the biggest eureka moment at 13:45, I can't thank you enough for this!
the same for me here
I am also studying engineering and I have a funny story for you Brian.
The other day, when finishing the automatics and controls course, the professor said: "If somebody did not understand something I have been explaining this last weeks during hours of lectures, you can search a guy named Brian Douglas in youtube and he will explain it in a few minutes with his videos. Have nice holidays". -- True story.
You have reached universities professors! Keep on!! Incredible videos. Lots of information explained clearly and quickly. Thank you for your amazing work!
That's pretty awesome! Thanks for sharing.
I hope every engineering class could be like this. You just solved my doubts in less than 20 minutes. Heartfully thank you sir
This video is pure gold. It helped me understand something that my course material couldn't in 25 pages. I finally am getting a grasp on system control! If I pass this exam it is due to your videos, so extremely helpful.
The 3 possibilities:
1.- The -1 does not get circled; the system is stable if there are no poles in the RHP.
2.- The -1 gets circled one or more times in a CCW direction; the system is stable if the # of times it gets circled is equal to the # of poles in the RHP.
3.- The -1 gets circled one or more times in a CW direction; the system is unstable.
Sir, you deserve a medal, this is exactly what I was looking for!!!!!
Asterio I'm glad it was helpful :)
great summary ! Sir.
I have a question of this video:
at 12:11, the gain on the w plane should be undefined, since the magnitude of zero phasor ( no zero for 1/s ) is also 0. According to the definition at 4:18.
brian got the assist but you fuckin slam dunked this shit.
you're a fucken legend
To clarify; if a zero (not a pole) is in the RHP the system is unstable, because the Transfer Function we're evaluating is actually the Denominator of the ACTUAL Transfer Function we're determining stability on. (GH is open loop, but X / (1+GH) is close loop). Nyquist difference between GH and 1+GH is just a shift of -1, so we evaluate GH as though its our transfer function, when in reality we're evaluating the Denominator of the transfer function. So what indicates stability, and what indicates instability, is flipped.
I.E. a pole creates a denominator of infinity, which is stable, while a zero creates a denominator of zero, which is unstable for the full thing.
Just wanted to help make that clear for anyone that missed it.
B Moore Thanks for adding this clarification!
B Moore
+Brian Douglas Mister Douglas I wanted to ask that in the last minute you said that there is one pole in the right half plane and two clockwise encirclement's of -1 so there are three poles in the right half plane. But in the previous lecture you said this Z=N+P. That clockwise rotation plus poles is equal to zeros in the right half plane. So which one is it? I am confused.
I believe this formula Z = N + P finds how many open loop (GH) zeros exceeds the open loop poles in the RHP, if the contour is CW. (If the contour was CCW it would be how many open loop poles exceeds the open loop zeros in the RHP of the s-plane). In this case N=2, so we know we have 2 open loop zeros more than poles in the RHP.
But since the open loop tranfer function is in the denominator of the closed loop transfer function G/(1+GH), this open loop zeros we found in excess are related to the poles of the closed loop TF. He showed in MATLAB that there is one unstable open loop pole, so in the end of the day the formula says that apart from that 1 unstable open loop pole, we will have more 2 (=N) unstable closed loop poles, so a total of 3.
Please comment if I said something wrong...
hbaqueiro you might be right. But I already gave my exam and I nearly passed my course. But thanks for the reply!
I love your explanations Brian. You explain the theory but importantly you also put the theory in a context that makes sense to an engineering student. You convey to the viewer the big picture of how the theory is used to solve real world and meaningful problems! Thank you.
Also a mechanical engineer here!! You are really a life saver and an excellent lecturer! it's really helpful for students like me that this subject is just something you should know a little about. You really make it funny! THANKS
You have put a lot of work into these with resulting clarity, perfect pace and additional resources made available. Thank you!
You're the only reason I passed my Dynamics of Systems and Controls class. THANK YOU!!!!
Believe me, you are the best among all the professor that I've seen
The way you explain is awesome. I have been relying on your videos to pass all the quizzes and assignments in present semester. I would be very thankful if you can upload the part 3 of Nyquist Stability Criterion which explains gain and phase margin.... Your efforts are highly appreciated. Thank you :)
Dude (Brian Douglas) do you know how many undergraduate lives you are saving by uploading these amazing videos. You are like Mother Teresa but with balls. I read the book but it takes so long to make sense of it....this is it man this is it!!!
Brian! you are savior...
I`m Electrical Engineering student in Pakistan. Our professor for the course 'Feedback and Control Systems' recommended this video in his lecture. I`m totally in love with the way you explained such difficult topics. Keep doing the good work.
HATS OFF 🙌🙌🙌
Fantastic lectures about the Nyquist Criterion. I am a student of the Engineering Physics programme at the Royal Institute of Technology in Sweden. Signed up to your channel and will be following your channel.
I am doing the undergraduate course of Control Theory right now.
You're awesome, I learned in 19 minutes what my teachers couldn't explain me in 1 semester!
I laughed when I heard you say "if you'd like to hear it from a professional professor", I'm here because my 'professional professor' did a terrible job explaining it and you're actually better. I'm sure Prof Gopal is great but I'll take your simple explainations anyday
You are really a gift. This is the most understood and sensible illustration of the criterion. Go on!
Thanking you from the bottom of my Heart for sharing all these in detailed insights about Nyquist Plot. Just a big fan of your lectures.
You Rock!
I imagine how many enginnering students just passed in control systems engineering class
I dont pass classes I pass away
Lol I have backlog ....I have to give Control system exam next month 😭😭😭😭😭
It's too tough and complex
Watching the video at a half speed made everything more clear :) You are an awesome professor.
thank you so much Brian, you are a perfect teacher, i feel sad that i did not found your videos in the beginning of the semester. wish you the best, you are number one!
You have no idea how much you've helped me this semester! Thank you for the time and the work you put into these videos to help everyone around the world! 🤩🤩
I just want to say that, if I pass my exam tomorrow, it will most definitely be because of you! You explain 10x better than my teacher, thank you so much for putting your time into making these videos! Subscribed ;)
Dude this is video was so helpful. Thanks alot.
The concept was taught so much better than our teacher at university.
Passed my exam, thank you so much Brian!
Congratulations! That's a good way to close out the year.
BRILLIANT example.... Thanks so much. Last video left me itching for an explanation on why bode plots don't help with unstable systems. This gave me some insight into that atleast.
Love to see people from outside of india also watch NPTEL videos and not just us college students; that's the love for engineering i guess.
Great video... both part 1 and part 2 really helped me get a clear understanding of the concept. and the fighter jet example in the end was awesome.
Im mechanical engineering (structure and material) student from Malaysia. I really hate this control system because i dont know anything what lecturer teach about ! Then, when i see your lecture on this video, its interesting subject actually !! you are great lecturer ! Thanks sir!!
this video really helped me in understanding nyquist... i really didn't quite get it from the lecture at the university.. but it was really made simple here. thanks a ton~! :)
you've taught me all these concepts within an hour what my professors couldn't teach me in 5 lectures
Thank you Brian, this saved me a lot of reading (and confusion)!
Nice Explanation and very well Understood. Thank you🙏
THESE VIDEOS ARE GOLD BRIAN !!!!
I love everything about your videos and I can't thank you enough for your help in my control systems course. I have just a small comment on the sound of them howerver: usually I listen to them with headphones, and I've noticed that sometimes the sound is a bit biased towards one ear (usually the right hand one). One example would be the video of stability margin, number 17 in your video. Also the sound level sometimes differ between your videos, which is slightly annoying when going through a playlist. Minor things really, but if you cold make the sound mono and level the sound to a specified level you would really reach perfection.
Thanks again!
Please check the examples in my channel as well and let me know if you have any feedback.
I go to a top 10 school and you teach it better than my professor.
Awsome lecture series on nyquist plots.... @ 18:19 .i have a doubt, if there are 2 cw encirclements of -1 and one unstable pole... shouldnt we expect 3 unstable zeroes.
yes indeed, you are right
One unstable (open-loop) pole is an unstable (closed-loop) zero. It's flipped.
Thankfully , @bmoore4313 clarified this things up in the upper comment section.
Thank you for making great video! from Korea.
man....i regret not finding this channel earlier
You left me amazed and speechless 🤐 , thanks alot.
i have to say you are the reason i passed my firswt test . lets hope you can make me pass the second one . thx and keep the good work
You deserve more than 10 million likes...
Awesome lessons! its so easy to understand the way you teach it
Brilliant explanation, a lot better than my professor, great job!
these videos ares much better than my professor and all my textbooks combined
Hi Brian, Thanks for the videos :) Appreciate it. Can you point me to few other examples where Nyquist plot shows the system is unstable while Bode says it's stable? I am interested in analyzing such systems. Thanks for your time and effort!
Only apropriate thing to say after this great video would be "svaka ti dala" in Croatian (roughly translated: "I hope every woman you meet puts out for you")
Awesome video, Brian. And a personal thanks for the email assistance. Hopefully I'll do well in the exam!
A very intense and tiring lesson, 18 minutes but actually 2 hours... Thanks for labour.
Damn you make me feel all my graduate school tuition is in vain! Actually, your demonstration is waaaay better than most professional professors, huge THANX!!
Although I have a Ph.D. in Mechanical Engineering from U of M, I absolutely HATED this topic of control. My concentration is in Manufacturing where I don't really have to deal with controls much. Of course I took required control courses in UG, got A's, but never really understood the true meanings of the topic.
Watched your videos.... So clear now. In just 1 hour, it feels like all the puzzles found its places.
I really wish my professors taught this course like you did...
Thanks man, I was really got deprressed understanding Nyquist criterion and root locus. But it is easy, thanks to you ;).
Dude,
you rock I can now finish my feedback controls hwk!!!
thanks mr.Douglas ! i m korean student majored in Control . this video is very helpful to me to study Control theorem easily. :-)
Thanks for the video Sir. It really helped me understand this difficult concept. Such exceptional clarity of A/V. Sharing and recommending this.
Hi Brian, I love your videos! It would be really cool to see your whole screen in a PDF or similar format, just to be able to see it all at once.
Man, Brian, you are that...the man...the controls man, man.
You are fucking awesome. Really you should teach everybody how to be a teacher. Keep the great work.
Could you make a quick video in witch to explain how to draw s+1 / s^2 +1 or something similar. It is a curious transfer function this one - I know how to draw it and a little bit of why we draw it like we do, but I would love to hear your explanations. By the way, you make the best videos !
Thanks Brian, you're a legend. How would you handle and draw the contour of systems with deadtime?
Couldn't be crearer man!. awsome work!. excellent teaching
Could some one explain why the phase is -90 degree in the s-plane at the time 13:45 and 14:28? I think it should be +90 degree because the points are in the positive part of the imaginary axis.
No, this is done in the right way. Have a look in the previous video. There he explains how the phase in the w-plane happens to be, how it is.
The phase of the W-plane phasor depends on the starting point of the Phasor in the S-plane. The phases of phasors starting from poles are substracted from the phases of phasors starting from 0´s.
In this case here we just have one single pole, so the positive phase in the S-plane maps negative in the w-plane.
Correct me if I'm wrong.
Greetings
@@hajo1570 i agree
These videos have been brilliant. Is there a part 3 to the Nyquist series? Gain and phase margins are mentioned as being in the next video - can't find any indication there is a next video.
As Always ...The Legend Douglas.
Great lecture man! Saved my day!
This is the better explanation I found on the Internet about Nyquist criterion(I viewed also the explanation of the indian professor you suggested). But there’s problem that I’m not able to solve: the only calculations that we do with the transfer function to plot it, is to consider it restricted to s value j-omega from j-zero to j-plus infinity... but: how can we be sure that the Nyquist contour is the one that include the right half plane (and not instead, the left half plane)? If we draw the contour of the left half plane we arrive to the same conclusion about the route from j-zero to j-plus infinity. Do you have the answer to this “tricky” question? Thanks.
Amazing job as usual! Keep it up Brian and thanks!
Bro,that helped like everything.Thank you so much,the way video is presented is really cool,i owe you this one,subscribed. :)
thanks brain, u have done great job, it was really helps me to do my exam well :)
Thank you so much! This makes so much more sense now.
Thankyou you give very good Excellent instructions.
Great video. I really appreciate your time.
My exam is in a few hours and this was in the syllabus. Thank you.
+Tejaswin Gumber Why haven't you studied properly??!
Great work Brian!!. . .I wish I would have found you last semester.
Is it possible for you to cover state space models??
Great video. I like your lecture more than my professor.
Could you please answer my concern of your video 1/s example?
at 12:11, the gain on the w plane should be undefined, since the magnitude of zero phasor ( no zero for 1/s ) is also 0. According to the definition at 4:18.
Great Video!!!
One querstion: HOW on earth did you get the TF of the openloop system of the F16???
I would love to read more of the FC system of that plane!
Thank you for your work!
Just Amazing !! :D You're an amazing teacher !
You are great! Thank you very much for these videos!
Brian, thank you. The explanations in both Part 1 and Part 2 are brilliant. 👍 However, you spoke a bit fast, and I had to pause and replay several times.😅
Thank you man ,good explanation.
Thanks a lot, could score on Root locus, Bode Plot, Nyquist plot which constituted 30 marks out of 50 for my end sems
Hey Brian can you tell why at 18:16 there are 3 unstable poles, shouldn't it be 3 unstable zeroes
for the imaginary part at 9:33 (written in orange) shouldn't there be a `j` in the numerator?
Thank you so much for these videos!
Thank you so much! Your videos are so clear :D
Hello. Nice lecture. Just wanted to precise something (actually is kind of something i'd like to confirm). I was using matlab to understand what you are explaining. I saw that proper functions do not give a gain of 1, but the gain equals the limit of the function when s goes to infinite e.g. if the function is, as in your video, (s+5)/(2s+3), the nyquist plot passes through the point 1/2 with 0 angle.
great explanation. thanks Douglas
@18:10
Why does 2 clockwise encirclements of -1 and one pole in RHP mean that there are 3 unstable close loop poles?
+Brian Douglas I noticed this too. Is that a mistake?
z = n + p, where
z is zeros of 1+KG(s)H(s) in RHP (i.e. closed loop poles in RHP)
n is clockwise encirclements of -1
p is open loop poles in RHP
So here you got n=2 and p=1, z=n+p=2+1=3. Three zeros of 1+KG(s)H(s) in RHP, which in other words is 3 closed loop poles in RHP
@@tsunghan_yu how open loop zeros in rhp becomes closed loop poles in rhp?
OL tf= G(S)=G(n)/G(d) so open loop zeros we get by putting G(n)=0.......(A)
CL tf=G(s)/(1+G(s)) i.e. G(n)/(G(n)+G(d)) its closed loop poles we get by putting G(n)+G(d)=0.......(B)
both eqn(A) and (B) are different.
pls reply if i am wrong
P sinha you are correct. My description of Z was not precise. I meant zeros of the denominator of the closed loop transfer function. I have edited it.
what a impressing sample in the end of the video
Excellent! Please keep adding videos :) for example digital control
Amazing. I will be buying your book
please upload gain and phase margin video.....
Hello, Mr Brian! I studied Control Theory Systems in Leningrad (now St Peterburg) in 1991, but not completed, because of marriage and moved to Ukraine. Thank you very much!
Awesome explanation ! Thanks a lot!