System Dynamics and Control: Module 4 - Modeling Mechanical Systems

[@jakehaselton3544]

i have learned more about Systems Dynamics, and differential equations in watching a few of you videos than i have learned from professors over the last 1.5 years

[@mrOmar432]

You are a wonderful human being. And you have the talent of breaking complex concepts into several simple parts. Many thanks for the great effort!

[@HomemMagroide]

What a wonderful way of explaining. This prof takes into account the impact of the topic on the student and takes his time slowly transmit knowledge. If he does explain this way in the classroom, then his students are fortunate to have him as professor.

[@mustafaozcelikors9074]

Every professor should watch Rick's videos and learn how to be great at teaching. Thank you.

[@jesusreignonhigh6732]

I haven't taken this class yet (taking it this coming fall) but I certainly agree with you.

[@picco_only]

reyis bizde bir ismi lazım degil hoca var. kontrol hocası. illallah ettirdi...

[@crazymonkeyVII]

This is gold! The only comprehensible explanation going in-dept on the subject on youtube. Thank you very much!

[@mohamedyosry6668]

what a great work , you deserve to with the top professors in this field due to your simplicity in explanation

[@Steve-kj9tx]

This is a great video! Unfortunately my dynamic modeling professor doesn't explain things too well and speaks with a thick accent. I see you put a lot of work into this video, I hope more people will watch it and will learn something like I did! Thanks Rick!

[@wisdommahami1484]

wow i was struggling understanding this in an online class in my school thank you sir for making it simple

[@victimv5320]

Amazing Rick, the way you simplify the complicated mechanical system .. I would request could you please explain similar fashion how to design the structures.

[@anasadaileh3670]

Thank you so much I love how you make things simple and easy I love your explanation and the useful useful information that you tells us professor you encourage me to learn and watch all your videos a single videos is like a whole course but in one hour I really loved you professor real professor

[@sfdko3291]

Set the speed to x2. Trust me.

[@kameelamareen]

made my day

[@장난하나장난둘-h2d]

im a korean student who had been looking for this kind of explaination. Thank you so much !! :)

[@AJ-et3vf]

Great teaching. Thank you!

[@sammohammad6256]

God bless you sir

[@manfredbogner9799]

Sehr gut

[@majdolineibrahim8451]

Thank you. Great job.

[@IzzyP688]

Thank you so much. This helps a lot!!

[@chenrigy]

Rick, thank you for making this extremely clear. However, I am confused at 19:30 when you begin to draw the FBD for m1 you specify two methods for determining the direction of the forces acting of said mass. In the first method, where you fix m2 and move m1 in the positive x-direction, the spring and damper elements (k2 and b) would be compressed upwards so the direction of the generated force should be downwards to oppose or restore. This would mean that method #1 and method #2 (where you flip the direction of the force in m2's FBD) would have forces acting in different directions. Can you clarify why choosing one method over the other would result to different orientations of the forces in FBD and how this would affect the solution? Thank you!

[@hillrickc]

Whether you stretch or compress a spring, the restoring force on the two ends will be opposite as long as you are consistent in the direction and sign of your displacements. If for example, you stretch the spring between m1 and m2 such that y is larger than x, then the two ends of the spring will pull the masses back toward the spring resuming its free-length. If you compress the spring, such that x is larger than y, then the expression for Fs2 = k2(y-x) will be negative and the forces will be opposite the directions drawn. If you express the force as Fs2 = k2(x-y), then the force is positive when x is larger than y and the directions of the force in the free-body diagram should be opposite the way they are drawn in the example. I hope that helps.

[@yldrmdenz]

Perfect teaching. Appreciated!

[@atouidjamel9608]

Great lecture

[@danielamoran2254]

really clear and helpful!

[@dronhwa]

+Daniela Moran exactly

[@maphinichokoe6072]

Thanx for uploading these videos. May you please upload model 15 of these lecture series.

[@severinmundl2710]

Thanks...great explanation!

[@kadirbakisen2830]

thanks for great videos

[@larrynj5131]

Thank you...This actually saved me from a quiz.

[@alemayehuwakjira7337]

For M1 if you assume same analogy with M2, why not the two forces on the upper side of m1 are acting downward?

[@hillrickc]

You can use the same analogy, but when the forces on the upper side of m1 are acting downward, you are assuming that x > y (and xdot > ydot). Therefore, the expression for the spring force would be Fs2 = k2(x-y) so that the expression is positive when the force is in the direction drawn. When the expression is negative, the force is opposite the direction drawn. The same logic holds for the damper force.

[@altuber99_athlete]

I found gold!

[@duino-x1766]

Very helpful, thank you

[@milkcreightronny]

The book you continuously refer to is the Conceptual Dynamics that you wrote correct?

[@hillrickc]

I have some other videos that follow the Conceptual Dynamics textbook, but this series follows System Dynamics by Ogata, though you could really refer to any introductory Controls textbook.

[@milkcreightronny]

@@hillrickc Awesome. Thanks for breaking this stuff down slowly. Very helpful.

[@shirinenferad3298]

Very nice and clear explanation. please let me know if we want to put a controller, It should be one controller between body of car and Tire, I want to know do we will have just one u(t) in our equation (in our state space vector) as output?

[@hillrickc]

If you added an actuator, for example something that generates a force between the car and tire, then your system would really have two inputs. One input from the actuator and another input from the road. The number of outputs would depend on what you were interested in.

[@danielgeorgiev7272]

Great

[@varundr9575]

how to design a spring mass oscillation system in which frequency change is minimized w.r.t change in mass .

[@mertturkoglu3561]

Whats the name of the book that I can find more example?

[@hillrickc]

You can try the book System Dynamics by Ogata.

[@erswati8351]

hlo sir, nice explanation. Sir can you plz make a video on how to make FBD of 2-dof quarter car model and how to write governing equations with piezoelectric material in series with suspension spring and also consider the damping of a tire. Plz reply

[@abdulkadirkhan5215]

sir can you help on how to control sdof system with piezoelectric actuator and sensor

[@ali64fahad]

wonderful

[@cubepain92]

thanks you sir, would you please make a lecture about dynamic vibration absorber?

[@samkelisiwem4160]

Thank you for this video, it's very helpful. I have a question though, how do you find the state space representation for a circuit with, say on displacement X there's a mass and maybe 2 springs(one in displacement X and the other between X and Y) and at displacement Y there's a damper (and the spring between both displacements) but with no mass? I don't know if I make sense, but what I'm trying to ask is how do we find a statespace representation for a circuit with 2 displacements but only one of them has mass

[@hillrickc]

You can have a look at Module 27b for some insight - kzbin.info/www/bejne/iJWki4GLm7x3prM

[@aboyousef2010]

Can we get the pdf notes for your videos?

[@hillrickc]

@aboyousef2010 You can access the PowerPoint slides that accompany the videos from the following link: www.dropbox.com/s/u7k7cf24md4zx1r/Slides.zip?dl=0

[@aboyousef2010]

@@hillrickc thank you very much Your videos are great!

[@alemayehuwakjira7337]

As long as other things are assumed stationary and m1 is moving up

[@niruban7132]

With the quarter car suspension, do you derive a transfer fn for this example anywhere in your videos

[@hillrickc]

+Chimeout Brah Unfortunately, I don't. The closest thing is that I derive the transfer function for the rotational example in this video in Module 5.

[@niruban7132]

+Rick Hill the rotational example you go through, could that be termed as a feedback control system (ie a closed loop system) ?? Also, love the videos they are such a huge help!

[@hillrickc]

No, that is not an example of a feedback control system. The input is a torque applied to the shaft and the output is the angular twist of the shaft, but how the torque is determined (and generated) is not included in the model.

[@niruban7132]

Ah i see. Besides the cruise control example in Module 13, do you go through any other real-world examples of closed loop feedback control systems?

[@hillrickc]

Modules 14, 18, 22, and 23 do controller design (algebraic, root locus, freq response), but they are more focused on the process, rather than on practical real-world applications.

[@pratikprajapati267]

excellent sir how to apply this control theory on practice basis.. I mean, how can I control any physical system by any microcontroller or microprocessor

[@hillrickc]

I have created some web-based instruction on using the Arduino Microcontroller (through Simulink) for controlling some simple systems such as a DC motor, a DC-DC converter, and a lightbulb. The pages can be found under the "Hardware" tab at the top of the page whose address is given below: ctms.engin.umich.edu

[@davidsonfellipe5286]

very good your video and its explanation, although it is in English and I do not understand rsrsrs I am student of engineering of automation and I am having a lot of difficulties in modeling of dynamic systems quarter car system, you could make an example of this with values ​​of the masses and constants of k, and c. Thank you very much in advance

[@mustafaefecetin]

Why don't you consider the masses of m1 and m2 into equations?

[@Ruddog12]

what book are you using rick?

[@hillrickc]

+Ruddog12 I use a variety of sources, but a book that follows most of the material I present pretty closely is System Dynamics by Ogata. Thank you for your interest.

[@burakesme3217]

Thanks sir, that was a lifebuoy :) By the way if you re-upload the video with noise reduction to kill background hum it will be flawless :) Regards...

[@hillrickc]

Thank you. I have begun trying to upload some cleaner versions of some of my lectures broken down into smaller chunks. You can see one example here: kzbin.info/www/bejne/pWmYZKOZlLGofq8

[@spinnie0]

There's a constant low frequency humming in your videos that is really uncomfortable on the ears. Had to adjust my equalizer to remove all lower frequencies to be able to listen to this video.

[@gleniosp]

Great!

[@corlfranco9371]

stickiness can feel good sometimes

[@ahmadmahmood2416]

i need lectures 1, 24 and 25

[@Vatea97]

Hi Rick would you share a contact mail for discussion purpose?

[@abdulrahmanblue8403]

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