PID demo
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- Опубликовано: 23 авг 2024
- For those not in the know, PID stands for proportional, integral, derivative control. I’ll break it down:
P: if you’re not where you want to be, get there.
I: if you haven’t been where you want to be for a long time, get there faster
D: if you’re getting close to where you want to be, slow down.
Motors, in general, don’t start or stop on a dime. So it’s easy to overshoot, undershoot, whatever. PID allows you to dial in those three concepts with numbers
Thanks Warlax 56 for simplifying the PID
تجربة مثيرة لفهم تأثير معلمات متحكم PID
تستطيع تحميل ملفات المشروع من الرابط التالي : drive.google.c...
Author : Dale Heatherington
in 1 minute and 28 seconds, without saying a single word, you have explained how PID tuning works better than any other article or video I have ever seen
Same for me!!!
Yes
Yes!
What she said.
BS
For those not in the know, PID stands for proportional, integral, derivative control. I’ll break it down:
P: if you’re not where you want to be, get there.
I: if you haven’t been where you want to be for a long time, get there faster
D: if you’re getting close to where you want to be, slow down.
Motors, in general, don’t start or stop on a dime. So it’s easy to overshoot, undershoot, whatever. PID allows you to dial in those three concepts with numbers.
P.s. read the video description carefully
Daniel Warfield good explanation, you really understand your shit. Thank you
@Hazem Ketat I doubt it. Proportional means speed is proportional to the displacement between where you are and the goal.
integral is the integral of the displacement over time, I think. that would mean that value would grow as time continued.
I'm not an expert on PID, but I do know calc pretty well, and the underlying mathematical principles of integration and proportionality wouldn't make any sense in reverse. Proportionality, by definition, has no notion of time.
This is the best explanation I've ever seen! Pure gold
@Hazem Ketat His explanation is correct. Think of it this way. You're tailing a car with an identical car. The ideal position is right beside the car you're following. The P(roportional) controller would control the "speed" of your car. If the car you're following increases their speed, you'll also increase your speed to be the same. But that means once you get left behind, you'll always be left behind (because you can't get faster than the car you're following to catch up). This is the steady state error. Increasing P value in this kind of system results in faster "speed" control, but because of the reason stated above, you can't get rid of steady state error.
I(ntegral) controller on the other hand would control the "position" of the car (because the integral of a speed function is a position function). This way you can get rid of steady-state error, because you're not only matching up the speed of the car you're following, you can also catch up, because while the P controller lets you get to the target car speed, I controller lets you get to the target car position. Add these two terms together and you can get more speed than the car you're following, and you can catch up if you're left behind. This gets rid of steady-state error.
Additionally, D(erivative) would control acceleration rate. When you're getting closer the the target car while catching up, it will slow down the acceleration rate.
Combining these three parameters, you can create a fast and responsive system (P) while being accurate and efficient (I) without the risk of damaging equipments due to the system overreacting (overshooting) (D).
Thank you!
Imagine watching this without knowing nothing at all about Control theory
i am....whats that??? PID
PsyZueiro product integration and derivation. in a system the difference between the output and supposed output for a given input is minimised by a closed loop system by tuning the input by a multiplication with a p parameter of error added to multiplication with an i paramer of accumulation of error added to multiplication with a d parameter of difference of error. this is really the most useful tool of control theory and cybernetics is indeed appeared based only on this simple technique
@@consciousart1 proportional integral derivative are the terms.
@@consciousart1 proportional integral derivative control. It gets its name from the calculations performed by the algorithm. You can also have p, pi, or pd control
@@sexyfacenation you are exactly right I know the case but product for p letter appeared on my mind sorry :)
I have no idea what this is and what's going on. But this is still more important than my spanish homework
Thanks. That's started our day with a good laugh.
Defend Armenia! Hoah... are you from Glendale?
@@vongunter9947 no, I am from Yerevan
The hardest I have laughed for years, maybe forever. Still laughing. More than brilliant. Thankyou!
Deberías hacer tus deberes de Español
If you already have a general grasp of what a PID Loop does, this is actually really straightforward and practical information for understanding how it affects real objects.
Thanks for the demonstration.
Hey,
So i ran into this, seemingly by fluke. I have read the comments explaining what P, I, and D mean. But I am not sure how this demonstrates what they are explaining. I am not picking up what is changing. The relationship between the lower wheel, I am guessing attached to the motor, to the wheel attached to the pulley with a metal needle seems to stay the same... What is he trying to do here other than just swinging them back and forth....
@@steve2547 hey, I fly quadcopters and recently learnt how to tune pids. It's basically the same. So p is like the sharpness setting, if you under shoot or overshoot, you can adjust p. D is like the dampening for p, you see those bounce backs? those are because the d is too low. I is like a stiffness setting, if your thing is all wobbly ( slow wobble ), increasing I will help that. Hope this helps!
@@abrahamtan9704 actually the ratio of I and D is the dampening.
@@BrosBrothersLP really? huh, I learnt something cool today
@@steve2547 Ok let me break it down for you.
PID is a type of control. It has different "parts" to it, wich have an influence on how to reach a certain point. In this case an specified angle.
The most left switch turns the system on, like "power on, and go to angle X!".
The dial right of that controls where X is.
Now by adjusting the dials on the right the parts for D - Derivate, P - Proportional and I - Integral of the controler can be adjusted.
Different amounts for that parts lead to different system behaviour. Th goal is to go from angle Y (starting angle) to X.
Every control system aims to reach the target point as fast as possible. Some system require tuning so it doesnt overchute, mostly for positioning controls, which in turn makes the control slow.
So depending on your application the control has to be designed towards the restrictions.
This experiment shows how the different parts of the control affect the way the target is reached.
P just takes the difference and amplifies the lead directly, for example a current or voltage. This leads to overchuting and a "waving" pattern around X. Its moderately fast, but is never precise.
D dampens the amplification if getting near X, which can make the control faster, but also slower to reach 100% X.
I integrates over time, which means that the longer you are not at X the stronger it gets. This increase precision but can lead to waving behaviour, called "wind up".
Hope this helps. Control theory is a whole engineering field in its own. Anti lock breaking systems, adaptive chassis, thermostates in AC units are examples of control systems.
I suddenly understand how to tune my quad, thanks for the video very informative
What are you doing here
@@keanumack3944 Learning to tune his quad
QuadCopter I hope you meant.
Wow, what a great way to help understand quadcopter tuning! This is a must see video for anyone building a quad. Thank you!!
The closed loop idle control system on my car uses PID. Tuning it was basically just guessing at numbers.
For those who studied control systems/theory/engineering and still didn't understand
P : Proportional gain (makes system faster, improving response)
D : Derivative gain (improves transient response, i.e. from before moving to settling)
I : Integral gain (improves steady state error, i.e. closer to where it should settle)
0:17 : Unit step input
Very bad transient (wiggles) and steady state response
0:23 : Proportional gain increased
System response is now faster
0:31 [PD]: Derivative gain increased
Transient part improved (no wiggles)
0:52 Integral gain reduces steady state error,
Notice the error it gets in steady state with decrease in integrak gain
You didn't explain anything relevant to the video.
What's the controler here(what's the actuators) ? What's the controlled quantity? What's the region of values we want to stay in? Why do we leave the region?
@@MrCmon113 ??? how was this not relevant to the video. They described PID, then timestamped examples of how adjusting the knobs adjusts the output. The controller would probably be some kind of motor.
Do any of those other things matter in this case? It's a simple demonstration, not an actual implementation for any real purpose.
I think you will find that those that studied Control Theory at university *DO* understand.
@@deang5622 well one of my friend didn't, so... (also look at 1st reply by MrCmon... those who studied controls should have that knowledge already, that's why).
Wish I had this back in high school lol
this video illustrates one of the most important points about learning -- quick iteration is key! Imagine learning this by watching water levels endlessly oscillate around the setpoint at a frequency of 0.05 hz...
Yeah Bandler was stating that people don't learn things too slow, they learn things very fast but most of the fast learned things are random, useless and dangerous for them. Now I will go browse some random internet videos.
My teacher has been explaining this for 2 years now and 1 hour before my exam I find this video. You saved my semester man. Thanks
I just love how without words, all of us just got intuitive understanding of what PID does and how it "feels" what parameters do.
При чем все понятно для любого языка общения!)
Не зря язык жестов так же считается единым для многих стран
1:29 seconds with zero words explained PID better than three lectures with 120+ slides
Entire day I have been reading papers and watching various videos and this simple video with no words explained it much better than all of them, amazingly simple! Thank you!
While playing with implementing PID in Unity3D I found that:
P: is just a vector pointing towards goal, that can be used as a force vector. The farther you are the bigger magnitude and bigger force to apply.
D: is predicting future by analyzing last and current P values. It acts like a break since it's vector value is pointed in (almost) opposite direction. D stabilizes motion and prevents overshooting.
I: this is harder to explain, because integral value not only don't help, but makes things harder to stabilize. It's main goal is to counter external forces, like for example wind or gravity. For example if you have Quadcopter that has GPS and can fly to a given position. Using only P and D won't allow to reach desired height, because gravity will become equal to proportional force so quadcopter will stabilize at some lower height and with stabilized position D will be equal zero (value - value = 0). In such case Integral becomes important since it is basically a sum of all previous P values multiplied by time intervals. So when a PID devices reaches a stable position far from goal integral value will build up which will increase PID value to reach goal despite all external forces.
Integral makes PID immune to wind, gravity, ocean waves and other external influence. Sum of P and D will approach zero when approaching goal, but I value can be anything. It should become zero exactly in goal overtime, but in real life scenario external forces will prevent to reach exact goal position and even an epsilon difference is enough to keep integral value at any level. At such stable state integral value will become opposite to external influence like gravity.
I been using PID control for my active rag doll in Unity for years… I can tell you one thing: my active rag doll system contains no Integral part merely because of its uselessness, so basically it’s called PD control rather than PID.
That was very helpful ...thank you
All i see is power , intensity ( i current) , and decay. Course done lol
Very well written, sir.
This my first time seeing or knowing about a pid on this video and I already know how it works and adjust it.its not that hard.
literally did an entire class on control systems and PID control, pretty sure I learned more from this 1.5 minute video and description than I did a whole semester, thanks university.
I disagree. But this is a helpful visual demonstration.
@@mattooi4322 I don't think you understand how bad my professor was... I'm also using ghoulish over kill
The missile knows where is it by knowing where it isn't...
And knows where will it be because it knows where it wasn't.
@@ChrisD__ And it knows it hasn't been where it wants to be in a while, so it's trying to get there faster.
And it wants a strawberry milkshake because it saw a kid with one
@@MaNNeRz91 lol
@@kushkiller7108 you better be smoking a joint right now
I woke up at 5 AM and found this video. I had 0 clue what I was watching but I watched it twice. I then Googled PID. Side note, inflamed pelvic disease, is a thing, who knew?
After doing a bit of reading, I now understand what I watched. Pretty cool.
PID is one of most powerful and versatile algorithms out there, whether for having a robot track an object, or a person drive a car. There are so many examples in both technology and nature that makes this tool for reaching and maintaining a goal state so useful (in the human body, this is called homeostasis and what provides us with our sense of balance and being able to walk upright, or to maintain a constant body temperature.
So you claim homeostasis is the same algorithm as PID? Sounds like it's the only algorithm you know and that's why you think homeostasis can't be using _any other_ form of closed loop control?
I spend many hours by learning PID. My professors couldn’t explain this in simple words. They used „science terms” which bored me af xD. Finally, I didin’t know how exacly it works... Until today. I swear, 1 minute of this video is more brighter, then hours of their talking in class xD
"if you can't explain something in simple words you dont understand it well enough" or something ... ;
dopiero sie zczailem po avatarze... Zbysiu! 😂
Yeah but as an engineer you need to understand the maths and theory to actually optimize a controller
Jakoś człon całkujący słabo pokazał co robi 🤷♂️
@Tomek Herman It is you who need to learn English better than to broadcast gibberish like "didin't ...exacly....more brighter, then" rather than blaming professors.
I’ve been trying to visualize what each does for months now and this video has literally made it all click. This is perfect.
Just got the exact same problem finally solved!!
Not a single word. And now I know what PID is. You sir, deserve a like.
Thank you so much that was the most easiest way I have seen to understand PID tuning. Out of all the mumbo-jumbo that's out there this really help show people like me that have to see it to understand it. So thank you I will say this video and reference it anytime I'm tuning. That was great thinking.
It is very strange. I never thought that a short video without words would be so informative.
That's what modern day education does to the human brain. We are not used to using our eyes alone to learn. The system has taught us to rely on our ears to listen to someone talk for hours on end to learn. Here it's completely visual. You see what he did and you see what happened. Your brain can understand and learn from that far greater and far faster than anyone could talk you through it. That's why hands on experience is unmatched!
The lack of sound or music made it even more educational.
BRILLIANT!!!
This video explained PID better than 3 years of school and 5 years apprenticeship as an industrial electrician. Well done.
Than you had a very bad teacher sadly
Explanation for those who have questions: The upper right hand switch controls the system power supply. The lower left side switch sets all the potentiometers to zero (down) or enabled (up). The upper pulley and pointer are mounted on a motor. The motor drives the lower pulley through the drive belt, which turns the position potentiometer as the system measured variable.
The left side potentiometer is the system position setpoint. The pointer, and the position potentiometer attempt to follow the position of the set point potentiometer. When the enable switch is down, the set point, position, and PID potentiometers are all set to zero. The effects of P, I and D can be observed by adjusting their respective control potentiometers. Most feedback control systems are tuned for stability using different settings of P, P and I, P and D, or all three. There are also I controllers but are not very common.
the PID parameter pots remain in effect at all times, or else the return of the position to the zero point would be uncontrolled.
I understand PID control loops. I've programmed servos, analog as well as digital parameters in a servo controller, and while this video demonstrates the concepts some explanation of what is being demonstrated would have greatly improved the educational value.
Equally confused by what I am observing. just thinking buy a stepper motor and learn to code
The system has two inputs: a switch and a knob. What do those inputs do? Maybe the knob represents some input, [0..1]. Does the switch, in the off position, force the input to 0, and in the on position let the knob determine the input?
Thank you very much.1 minute 28 seconds has cleared my 9 months intense work of understanding PID in vain.
The best explanation of PID loop tuning as a visual that ive seen. Nice job.
My favorite oral explanation is thinking of the throttle in a car.
You’re at a stop light.
You want to get up to 35 mph in the fastest time possible.
You hit the throttle hard. (high P)
You’re approaching 35 but you dont want to exceed 35.
You throttle back before you reach your desired speed.
This is (D)
You want to maintain 35 after reaching that speed. minor throttle regulation is the (I)
Yep. Now I’m certain that I’ve watched too many useless machine videos to get this treasure in my recommendation.
Well, this useless machine evolved into an interactive model
@@supernova5434 so what you'r saying is useless machines are now useful and useful machine are now useless?
When I studied control systems last year, I found it hard to visualize what the individual gains of the PID controller actually did. This simple 1 minute video was more helpful than any of the plots in MATLAB I made to visualize how a PID controller actually works! Too bad I didn't see this last year haha. I miss the course actually, it was really fun and we got to regulate a double tank system with a PID controller as our final project!
Hi thanks a lot 👏 I‘m a remote pilot, I work with drones. Was having trouble understanding the PID tuning. Watching your example brought everything to light 💡
Take care 🍀
This video is what finally made it click for me when I was taking my control systems class in college about 3 years ago. I ended up getting a C in that course, but now I work with hydraulic control systems every day and I love it!
We were made to do this with a heat source and a temps sensor. -it took hours making changes to the parameters and plotting. This is a nice visual introduction - well made.
This has been by far the best explanation of how to tune my 3d printer heater PID! Thank you!
I learned this when I was 10 years old.
I was trying to make a group of robots that had several "leader" bots and a bunch of "follower" bots. The idea was to have an algorithm that would select the most advantageous leader and then have the followers follow it around like a train with no physical connection.
I had to suss out the details on my own by trial and error.
I finally realized that I needed three algorithms to insure that the "train" didn't decay into chaos.
My instructor was amazed. He explained to me that I had implemented a control loop based on calculus.
Thing is I had not taken calculus yet and had no knowledge of it whatsoever!
A demo IS worth TEN THOUSAND words and diagrams!
I’ve watched countless PID tuning videos and this, without sound just explained it all to me! I can now make my car idle perfect thanks dude 😇😇
With the help of..DR RORPOPOR HERBAL ON RUclips i have been cured totally from PID....🤩🤩
When new engineers is about to tune their first control system, i always go through the ziegler-nichols method with them. It takes away 90% of the confusion. Also, remember, that many tasks can be solved with using only PI making the tuning more straight forward. The D part is incredible at counteracting load change, which fx is the key to success in almost all heating and cooling systems.
I have been waiting for so long for this kind of comment.
The problem though is for years 'experts' try to teach PID with ridiculously complex maths that turns 99% of people away (mainly Laplace/Fourier transforms), while a simple video explains PIDs with far more clarity than any amount of pages of Laplace transformation mathematics does.
People can learn PIDs much simpler and with much better knowledge of how to tune them properly using an explanation like this coupled with real world trial and error using a gyroscopic drone or a simulation like the computer game 'From the Depths' which has an excellent implementation of PIDs.
Tip: best way to tune PID is to tune P to get it mostly there, then D to smooth it, then I
Can you explain to me abit more what i does?
@@beatboxdailyshorts5885 you're better off finding a tutorial, but a PID loop has 3 variables and 3 constants. You set the constants, and the variables are set via how far away the input value is from the desired one
Each variable is multiplied by a constant in the P I D loop, so when you're tuning it's best to start with the variable multiplying P first, since that's the variable that's set based on the difference between your expected and actual values. D is damping, and is based on changes in P and tuning that next makes it less jumpy. I is the variable representing over-correction. If after tuning P and D, your actual value overshoots your expected, add some more I
And suddenly I understood how to tune my quad. Thank your so much, sir. Maybe you don't even know what I'm talking about but your video improved dramatically my drone pilot skills!
I somehow got here without having a clue what this about, and while the comments have only confused me more, I am thoroughly convinced by them that this must be a great video
I sir salute you. Nothing else has ever made this much sense. Thank you so much for this beautiful demonstration
here i am, trying to fix a broken lamp and i stumble upon this, i have no clue what this is about but i like it
Sometimes, that's the story of life....😁
I have just graduated with a PhD in PID control systems, specialising in the pre-care and post-maintainence of speridal and non speridal PID systems and I can therefore confirm that this is one of the most accurate tuning methods out there, that is available, for those that tune.
So uhhh... what does it tune? A guitar?
Used it for a 47 year career in instrumentation. Can be used for almost all applications. Alpha and lambda methods still use the basic PID
if you can’t figure PID without this video you shouldn’t be anywhere around technology
Me: *aggressively searching for a map*
This video: "Took a wrong turn in the algorithm didn't ya?"
One of my hardest undergraduate classes.... Come back to haunt me. NO PROFESSOR, I REFUSE TO FIND THE ROOT LOCUS.
Absolutely fantastic visual demonstration!
You could make a fortune selling this device as a learning tool!
This is truly very genius. All you need to know, almost, about PID operation in this very short video.
RUclips recomended this video to me. I didn't knew what it was untill I realised it's an electromechanical laugh machine!!! And it's adjustable!!! Wow,the things we can see today!
Having recently completed a Master course in robotics, I really wish I’d had one of these, or been assigned to build one. So clever and clear.
why would someone need to tell you to build one? just build one
@@justinc2633 Because maybe he's one of those people who knows it all on paper, but has no practical ability? (Like every graduate engineer you meet in the field).
@@nickmaclachlan5178 haha yeah fr, im not an engineer but i love building things like this, if i had gone to school for it id have some cool projects under my belt
I will.
When I've finished the other cool projects I'm working on.
This is amazing. I broke my brain trying to understand PID. After watching this a couple of times I actually understand what's going on.
you have made me understood how to tune my mind, my soul, my whole essence with this video. i am forever grateful and will remind everyone until the end of time of this video. this is the new theory of everything
What a great educational tool! Visual aids really help solidify theory in a way that is much more intuitive than crunching numbers. Great demo!
Believe it or not, this helped with tuning my quadcopter , cool
Patch..... Genius !!!!
Best description ever..... eher Single time when I must explain PID , I will Show your Video .
Perfekt
Probably the best demo of PID control on RUclips.
Very cool. Everyone in the Instrumentation world is smiling while watching this :)
This explains why everyone attacks me first at the duel arena.
Not that kind of pid 😂😂
Selling pid 2m
The most instructive video on this subject. Shows more than diagrams or formulas or numbers.
Thank you for this, your video, without a word, explained to me in a few seconds what I have been trying to understand for who knows how long! Watching this, everything I have learned, trying to figure it out, just fell into place. Thank you.
Am I the only one watching without even knowing what PID is? 😂
🤣🤣🤣🤣🤣 Proptional integral derivative control used for optimizing the control loop
One application of PIDs are the settings in a drones flight controller. There is a lot going on when flying a drone, many different effects and inputs that the actual quad experiences, and the PIDs control how much influence each aspect affects that actual flight control output.
Nope...
Не парься. Я тоже в этом ничего не понял.
So what did you see in this video?😂
It should have a weight on a spring at the end of the arm. Then I and D would really come in handy.
Thanks this is a seriously excellent visualisation to explain PID controller for those that don't know what PID its what's used to stabilize the electronic control of things like drones and other control circuit loops.
I dont even remember how many videos I watched trying to get PID idea. Your video should be first hit whenever someone search 'PID'.
This is really clever, thanks. It would also be interesting if you showed controller responses to error causes by pushing the sensor with your finger. Maybe a part II?
just passed system control last semester. i like how youtube recommend this now :)
This isn't what PID stands for, but it helped me some:
P-rimary speed
to
I-ncreasing speed
to
D-ecreasing speed
being flying quadcopter and try understand quad for 8 years and still unsure... you just brighten my mind in 1 min
Это лучшая демонстрация, из тех что я видел.👍
Так а че это за хрень?
@@etl9143 ПИД регулятор, точнее демонстрация влияния коэффициентов на его поведение.
the best example
Higher P = Quicker and snappier response
Higher I = Less wavier response
Higher D = Smoother response
This video demonstrates PID in general with no words spoken ( °O°)
The description was a life lesson in itself. Thanks I needed to read that.
Very simple video with no words but it really says a lot, thank you for this great visual explanation.
Mho. Hands down, BEST explanation (w/o words of course)!
Thank you. I'm sharing with the world.
That explanation in the description nailed it so well! Thanks a lot for the video and the explanation!
That's the first time I've run into PID hardware. I could play with that for hours. Very useful for robotics I should imagine. Thanks m8. Keep well. :)
I’ve learned _something_ , i just don’t know what.
Lolololol!
I was waiting for it to become unstable. Great demonstration, nonetheless!
At some point when reducing D you could see overshoot with a damped oscillation. That was close to getting unstable. He fixed that by reducing P
The combination of the video's presentation, and discussion in the comments, helped me to understand PID control. Thanks.
For cruise control on an ICE car, the parameters can be set different for when the pedal is depressed vs when released. Transmission gearing, RPM, and available torque are all relevant to the settings. Anticipating the road slope is hard. The engine may not provide any braking on down-slopes unless manually shifted into a lower gear.
This makes optimizing cruise control rather difficult with an analog controller, and usually means that drivers will shut off cruise control on hilly terrain.
Now I understand the principle of adjusting the regulator! Thank you.
I started my controls class a couple of weeks ago and this is really cool.
I had no idea what PID was but now I feel like I understand what it is just by watching this video. Still have no clue where it's used, but have an understanding how it works. Very cool
For an everyday example, think about balancing a drone/quadcopter.
Have to agree with a lot of the other comments. This is an excellent representation of what PID tuning can achieve.
Nice job.
Увидимся в рекомендациях через 10 лет
OMG that is effing genius. I just wanted to see more...
Good to learn how Pelvic Inflamatory Dissease works
I think I understand the concept behind this video and its really simple explanation of how pid works and the impact of low and high values. Great Video!
adding physical interface for P, I, and D on my control schemes changed my life forever. Joint operating weirdly today? Just retune on the fly! If you ever remake this video you should add a part showing unstable positive feedback!
Для чего такой пульт?
This is better than any explanation I've heard so far. I'm glad you made that box and the video.
I am used to say that you have tne power of synthesis. You have explained all PID concepts once for all
Fantastic!
It remember me the fruit loop's Sakura plugin.
Oh hi mark
I wish I had this back when in college.
Wow. PID controllers were never explained well to me at all. People would just tell me that it just works. This is infinitely useful.
This helped me with pid tuning more than hours of tutorials.
Great little expo...takes it out of the gui and into the real world in a very visual way, would be interesting to see the effect of foc along with encoders.
Add lcd for display value
This is sort of what I was looking for from hours for the sake of my assignment.
Wow, this is the most clear and easy to understand video about PIDs I've seen so far.... and its from 2016... thank you !