The Root Locus Method - Introduction

The Root Locus method is a fantastic way of visualizing how the poles of a system move through the S-plane when a single system parameter is varied from 0 to infinity. I show how to interpret the locations of poles in the S-plane, and how they are tied back to system requirements.

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If you have any questions on it leave them in the comment section below or on Twitter and I'll try my best to answer them.

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[Paddydothrock]

I never thought I'd see the day when someone could produce a youtube tutorial video which progresses in a logical way, makes sense throughout, doesn't have a highly irritating voice, uses a decent microphone and doesn't constantly fumble with it, stays on topic and has not just legible but actually impressively neat writing..
Thankyou so much, yours are the best tutorial videos I've seen.
Please consider giving some lessons to Kahn Academy.

[ianhanley]

I am a fifth year Aeronautical engineering student, currently using root locus to design aircraft flight control systems. This fifteen minute video is a more complete, effective and absorbable explanation than I have been given throughout my degree.

[neroskywalker]

I've learned more of the basis of root locus in this video than in my whole course in the university.

[BrianBDouglas]

Hello, I briefly cover that in my video called Stability of Closed Loop Control Systems starting at around 6 minutes. The even faster answer though is that the time response of a pole is e^st, where s is the location of the pole in the s-domain. If s is negative (left half plane) then as time get's larger e^st gets smaller (stable). If s is positive, then e^st gets larger as time increases. No matter how many poles you have, it only takes 1 unstable pole to drive the system to infinity.

[abhay]

This is the greatest video I have ever watched throughout my electrical engineering degree. The clarity Mr.Douglas gave me is insane. Thank you

[iAMCobalus]

You are literally the GOAT. You broke down a concept and explained it so well with amazing visualizations. This video deserves an award!

[RickSettle]

I'm a retired technician. I spent 43 years in various aspects of electronic control systems. Everything from flight control system on B-52 bomber to re-heat furnace control in a steel mill to general control system in a power plant. Sad to say, I was lost in the first minute of your lecture. It would seem that the world of system controls has left me far behind. I'm glad I no longer depend on the knowledge to put food on the table.

[sagasa]

Wow as someone who's currently struggling with a flight controls class with a non native speaking professor and no controls theory background, this is GOLD ! Thanks so much

[NTNscrub]

You helped me understand the purpose of a root locus in 5 minutes better than my prof did in two lectures. Thank you.

[anantchopra]

One of THE best videos I've ever seen on Control Systems. I learnt far more from your video than my control systems course at my university. Amazing explanation with wonderful insights! Hats off to you for producing such great work!

[dinmukhamedzardykhan]

I am subscribed to you forever.. A lecture have never been so clear..

[santiagoricoy]

I met an old coworker of yours! She heard I was doing controls and immediately recommended your videos; I smiled and said, yes, I've watched every single one.

If I taught the class, the lectures would just be practice problems, and the homework would be to watch your lectures. 😂

Also, at about 7:29, I thought the imaginary portion was the damped frequency, not the natural; I thought the requirement forms a circle. Anyone able to help me understand?

[kdmq]

My professor never explained everything up to 6:30 and just explained root locus and threw me off for half the semester. I should have skipped more classes!

[Lolwutfordawin]

my uni has done an awful job at online classes, these series of yours are a life saver! so wonderfully explained!

[potatoperson]

Fantastic lecture! I appreciate how thought out and organized your learning plan is. I will be watching the whole playlist.

[bobseagull]

It's interesting to see just how much people appreciate good quality videos. Nearly a million views for the nerdiest content on Youtube. Congrats and thank you for your work!

[aminijooni]

you're my hero Brian. well explained and super easy to understand. thank you

[myonlynick]

0:00 up to 6:30 is PACKED with a load of insight info!

[shovon]

This is a gold mine for any control engineer who is still in the learning phase or even for those who is just revising man

[DhirenDave-vg]

The way you have explained the concept with very illustrative examples is fantastic. You are doing a great service to the engineering community by this effort. Please keep it up. Thank you.