Find Range of Gain K For Stability Using Root Locus Plot

How to find the range of the gain K for a system is stable using the system's open loop root locus plot. You will learn to use the MATLAB functions rlocus, step, and how to navigate root locus plots.

[someshsangwan]

thanks sir, before watching ur video i searched many videos on youtube but not satisfy but now everything is clear

[klocmod]

feels like a god is talking to me from above, that sound, hehe, thanks sir!

[antonisnic]

thank you man, i had the same question. Straight to the point

[jamrockpirate]

thanks for the vid, now im able to finish my control system lab

[carlosazevedo]

A nice and simple example to help us grasp into the basics of plotting root locus diagram.

[jortiz]

I'm a little confused on how rlocus() is implemented and it might be a source of my problem. rlocus() in MATLAB assumes a gain in the feedback portion and you must choose the forward-feed system as described in MATLAB's rlocus() help page. Every textbook I have seen always places the gain K in the feed-forward (open loop) part of the diagram. I am trying to find values of K for my system which is in the form given by most textbooks, but it appears that MATLAB is defining where gain K is differently and I believe is what is giving me wrong answers. I am curious as how you've gotten yours to work.

[muhammadshariezal]

thanks for the video, but how do i insert the denominator if its complex number

[Jnglfvr]

I'm not sure why you are plotting rlocus(T) because rlocus(G) ARE the closed loop root loci already. You can determine what happens to the roots of the closed loop function as K is varied simply by looking at rlocus(G). rlocus(T) does not add anything.

[AhmadTalkss]

What if it’s touching the IM axis twice

[conbatengineer]

Dude did you recorded this while taking a crap in a restroom?