Video: What is a PID Controller?

At first glance it looks a lot better than the vids I've made! Kudos.

If you have (access to) a Mac, I can highly recommend "ScreenFlow". It can record multiple screens, multiple cameras and audio at the same time, and provides a really good post editor for mixing down the video, with slo-mo replays, transitions and many other effects, PIP, etc.

All for $100. Excellent value, even just for the post facilities (i.e. even if you never make a recording).

Nicely done.

Well done. Your well spoken, I heard just one heavy sigh before you add the I. 14min seemed to go by quickly.

The demo is nice, maybe a Tach display and a angle display.

And better lighting, maybe you can shrink your self into a PIP and just show the demo.

Cheers

I've been fiddle-farting around with this for ages, starting about a year ago with "what would it take to make professional quality video". Not having infinite money, I didn't go that route. I finally managed to whittle my expectations down to something I could actually _do_.

I am partially trying to sell myself here, but better lighting would certainly be a Good Thing -- there's some known cheap ways of doing these, which I'll probably employ next time.

I'm using KdenLive for editing, and it's pretty good -- at least, its capabilities are well beyond mine. And at $0, its price is infinitely better.

The muy-expensivo camera is my cell phone. It was realizing that I had something ON HAND that would take adequate video that really pushed me over the edge.

As for simple recording and editing mistakes, the points that will be different next time are:

1: I'm working off of (essentially) a bunch of slides, and you can see me looking at them as I talk. I certainly don't like the looks of it. 2: There's a number of places where swear words, tongue-twists, and nose- scratching was edited out on-the-fly, causing jumps in the video. Again, they detract from the video.

Instead of trying to do the whole video in one take (and failing), I'm going to study _one_ slide, _hide it_, turn the camera on, do _that one slide's worth_ while _looking at the camera_, turn the camera off, repeat until _that slide_ is good enough, turn to the next slide, and repeat until done. Then I'll edit them together with suitable transitions.

This presentation had ten slides, so if I do 90 seconds and flub it, I can just stop the camera, take a few deep breaths, and try again.

3: The lighting could be improved. Just a few lamps off screen would have made it better, but I was in "dammit, just get 'er done" mode -- which is why it got done.

Not really on the "immediate" list, but room for incremental improvements:

4: The filming spot could be better. That's my very own desk and workbench, just cleaned up for filming. I'll probably stay here for now, possibly with incremental improvements, but if I should happen to get a really strong response I'll make a better spot. 5: I'm doing this entirely on my own. If I can get a camera-wrangler and general coach in here while I'm filming that would help. Fortunately, I have under-employed family members. 6: Editing and closed-captioning, ditto. Unfortunately my general attitude toward new things is "dive in and keep screwing up until you get it right", while my wife and kids' attitude is "no, won't try unless I'll get it perfect". Maybe I can get one or more of them to take classes...

Oh, and a quieter @#$% chair.

You're just as bald as I am!

(Oh, and nice video! :)

Nicely done.

May I suggest that future videos be done in something other than Flash, such as HTML5: For now, there are some Flash to HTML5 converters available. I have no idea which is best or how well they might work:

Suggestion: Take a clue from Dave Jones and fill the background with an impressive collection of test equipment: That adds credibility to your video. (Perception is everything).

YouTube takes my mp4 files and does what it wills with them. I know it reduces the resolution for most people -- at least I assume that you're not seeing all 1920 x 1080 that I uploaded. Maybe there's an option for one of us to ask for flash vs. HTML5 -- I'll see if I can figure out if that's my option.

I have a pretty sparse set of test equipment, actually. A nice Agilent mixed-signal scope and a Rigol spectrum analyzer are the highlights; it goes downhill from there all the way to a 1950's-era Heathkit RF signal generator complete with crinkle-coat paint.

Besides, the most important test equipment in the room is my brain -- the rest is just for convenience.

One of the videos I plan will show the test equipment that's built into nearly any closed-loop control project I build: there's a swept-sine analyzer in that software that lets me analyze both the arm position loop and the motor speed loop. I can take the resulting data and use it to tune the system.

YouTube adjusts the video to correspond to what the internet connection and computah can handle. I'm bandwidth limited by a

1.5Mbit/sec DSL connection which shows your video as 360p. I'll try it again tomorrow on my office cable modem connection, which can do 25mbits/sec and should show at least 720p. However, even at the lowest resolution of 144p, the video looks acceptable but blurry on my 24" 1680x1050 monitor.

I don't know why it ended up as Flash instead of HTML5. YouTube recommends uploading in MP4 (H.264) which should have been transcoded to HTML5: Check the list of recommended settings and see if there's anything different.

Vintage doesn't matter. It's just a collection of props that add authenticity to your presentation and makes it appear that you actually work with the things that you are discussing. It's much like a mad scientist movie always features a sparking Jacobs ladder, a sci-fi space program has a wall full of flashing lights and an oscilloscope displaying a Lissajous pattern, or until fairly recently TV news programs had the sound of a teletype machines clattering in the background. Viewers expect electronic presentations to have a wall of electronics. Don't disappoint them.

True, especially since your presentation is almost an infomercial advertising your services.

Ever notice that law offices always feature a wall full of legal books behind the photo of the attorney? The books are for show. Today, attorneys do their reading online with dedicated programs, LexisNexis, Shepard's, Westlaw, Fastcase, etc. The books are purely for show. If you look at them carefully, many are probably seriously out of date. Same with test equipment. If you look carefully at the equipment behind Dave Jones, you'll notice that there are few test leads plugged into the equipment, none of it is powered on, and there's little in the way of the usual boxes, attenuators, isolators, adapters, clip leads, and related trivia necessary to make the test equipment do something useful.

Yet another suggestion. Try not to put yourself between what you're presenting and the audience. Sitting to one side, as in your video, is acceptable. However, if you're showing something larger or more complicated, you may want to put it on a table between you and the camera.

One more and I'll quit (It's 1am here). If you look at the various Dave Jones videos: You might notice that the camera is well above Dave's head and looking down at Dave and everything else. That's intentional. There's lots of psychology involved, but basically it gives the viewer a slight feeling of superiority, which generally a better view of what's on the table. Your video puts the viewer slightly above your eye level, which makes them an equal to you. If you're trying to present something to other engineers who are competent in their areas of expertise, that's perfect. However, if you're trying to attract a general audience, who knows nothing about control systems, I suggest that you make them feel a bit superior by positioning them above eye level. If you want to intimidate the viewer, set yourself up as the leading authority on the topic, and probably chase your audience away, put the camera below your eye level.

I know next to nothing about PID controllers and would be very interested in seeing how it's really done. You mentioned cruise control. Practical examples are what interest me.

Well done! The use of the fan for illustration was a great idea.

Really good if you somewhat understand it.

But ...

1) beginning: explain the hardware. Motor with reversible fan What sensor(s) in base? Position etc What is the static balance point and how does that affect all.

2) Show what overshoot is. e.g. manually move the arm back indicating that is the overshoot.

A little light on integration and differentiation explanation. A little more would be extremely helpful. These are important concepts as you well know.

I give you a 98. (lol)

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Tim Wescott prodded the keyboard with:

Thank Tim, Just watched the video. Reminds me of Uni. :-)

After finally watching the whole thing, it's great! I think you already captured appropriate changes to make it better, so nothing to add here. It's always good to see somebody provide an intuitive explanation for things instead of focusing on the math (which is also important, but the math usually gets explained to death).

Yet another another day in computah hell. I run Firefox 46.0.1 on Windoze XP in my palatial office at cable modem speeds and still get Flash as 360p. I would have expected higher resolution and HTML5. However, when I switch to Chrome Version 49.0.2623.112m (last version for XP), your video auto plays in HTML5 at 480p. I can also force it to 720p and 1080p and it plays without buffering.

I also tried both the Firefox and Chrome browsers on Win 7 and Win 10. Here's the table of results for what appeared as the default player and screen resolution:

Firefox Chrome Win XP Flash 360p HTML5 480p Win 7 HTML5 360p HTML5 480p Win 10 HTML5 360p HTML5 480p

So, in Chrome, everything is working normally and correctly, but in Firefox, I have a problem only on my XP machine. Oddly, both Chrome and Firefox on XP show that HTML5 is supported and is the default: I still don't know why my Firefox default to Flash, but I think you can safely ignore this oddity as it seems to be a problem with my XP machine.

Thank you Tim, really nice to hear the fan working harder/softer - an inspired choice of actuator!

Good clear demonstration, I now can't wait to see a demo of the effects of too much D or too much I and not enough D / I etc and then an introduction on how to tune these or even explain how self-tuning works.

piglet

Yes! I had the same questions.

--Eeyore

I'm not sure if I'll do self-tuning, but yes, the other two need to go into a video -- or two, to fit into YouTube's time limits.