Hey guys, I’m new to FRC and I am on prog team. My team is using some pretty advanced control stuff like LQR + kalman filters. I am dumb and can’t figure out what is going on. How can I learn this? For context, we are using it on the elevator and the arm…
You’re not dumb… you just haven’t asked (yet).
Have you asked your current or immediately-previous programming team to help you work through from your current level to where you want to be?
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My prog lead isn’t exactly the best. He told me to just figure it out ;-; so now I’m kinda stuck
theres a book control theory for frc which goes over this, but it can be pretty intimidating. ghe wpilib docs articles on pid are a good place to start wrapping your head around controls
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yea i saw this and i was pretty confused xD
id start by working through these, they can be dense at times having the interactive articles helps build an intuition for it. As for kalman filters, there are some videos on youtube that do quick ~10 minute summaries although i’d have to go looking to find them. If you don’t mind me asking, what sort of math background do you have at this point?
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MATLAB tech talks are also pretty good
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@oman19 to tack on - Tuning a Flywheel Velocity Controller — FIRST Robotics Competition documentation - feel free to jump straight to the tutorial if you’re just excited to get in. Fiddle around and see what you can make happen. Once you’ve got some intuition for what’s going on, back up to the other docs pages to read more
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The subtitle of Tyler’s book says it all - Graduate-level control theory for high schoolers. You’re not dumb if you don’t understand Kalman filters as a high school student, especially if you are early in high school. I’ve seen plenty of crying college juniors and seniors looking at the scores on their exam in optimal control theory.
Is it possible that your programming lead blew you off because he doesn’t understand it enough to teach it? Does your team have a mentor that introduced these topics and can help you?
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The title says it all but I think the Graduate Level part needs more emphasis than the for high schoolers. This book is not for most high schoolers and not even most college grads. It is a complicated topic Tyler made as simple as he could but there is a lot to take in.
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Thanks! I am in calc bc and I know a bit of linear algebra.
The way I think about Tyler’s book is that it’s a textbook. It’s challenging for any student to just be handed a textbook and be able to read and understand it without a teacher providing scaffolding for student learning—presenting lectures, answering questions, giving homework problems, etc, and in general being able to spend more time on material that a student may be struggling with.
Prerequisites are also key here, a lot of control theory is difficult to understand without linear algebra and at least some calculus.
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That could be possible xD Our team doesn’t really have a mentor that teachers. It’s more of a student based team.
Absolutely. I have a comp sco degree and a minor in mathematics. I found it useful but heavy. Admittedly I had no control systems exposure until I became an FRC mentor and linear was 30 years ago and not my best math class by far. I keep revisiting as I know more and it is more meaningful each time. There are still concepts there that are beyond my full understanding. Also admitting that my learning speed wasn’t what it was when I was in high school or college.
then youre already ahead of where i was when i first tried to read that book. Id recommend watching 3blue1browns linear algebra series and his first video on his “tourists guide to differential equations”
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Thanks! Should I read the whole book? Which sections of the book should I read? Also, I would love to like your comment but I reached the limit ;-;
id recommend reading it in the order it is written, since it tends to build off earlier concepts. how far in you go depends on how much you are interested in and can digest, you probably should take it decently slowly to understand it. id definitely recommend watching the 3b1b videos first though
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You absolutely must watch the 3b1b videos or work through a comparable intro linalg curriculum before starting, or else the matrix math will eat you alive.
The matrix math is not hard to read once you have a feel for the notation, but it takes some work and thinking to learn the notation. No way around that.
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+1 to all of this and the differential equations one was also great for me to build my intuition around state space
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I would highly recommended reading Brian Douglas’s Control Theory eBook and watching all his control theory (or at least all the beginning ones) - https://engineeringmedia.com/. He try to explain it in a conversational manner and will allow high school students who doesn’t have the math background and understands the concept. For videos, you want to look under his website since he stops post on his own youtube channel once he started posting videos for Mathlab.
Control Theory isn’t a computer/programmer thing but it’s also in Electrical Engineering, Mechanical Engineering, etc.
His control theory lectures - https://www.youtube.com/controllectures [these are all the basic intro. all the adv topics can be find from his website’s video section]
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