In case it is helpful, all my Flight Mechanics videos in a single playlist are located at th-cam.com/play/PLxdnSsBqCrrEx3A6W94sQGClk6Q4YCg-h.html. You can support this channel via Patreon at www.patreon.com/christopherwlum. Please let me know what you think in the comments. Thanks for watching!
AA516: Great explanation of the different modes! For my final, I am going to be doing the visualization. Can't wait to get it working to see them in real time!
As always, another very helpful video! I really appreciate how your videos can distill days worth of textbook reading and cross-referencing into a single video.
AA516: Finally! This is my most awaited video of this course, and it's great to see everything comes together to help build an intuitive understanding of these modes.
Hi Ahmed, Thanks for reaching out. If you have questions or would like to request a video, I hope you'll consider supporting the channel via Patreon at www.patreon.com/christopherwlum. I'd love to have you as a Patron as I'm able to talk/interact personally with Patrons. Thanks for watching! -Chris
AA 516 This is such a cool lecture, you did a great job making such a complicated system intuitive for students. I have a canard pusher prop drone that I am designing in my free time and I was considering mounting the motor onto a 2-axis robot arm to make a "vector thrust propeller" to replace the rudder. However, because of the gyroscopic precession caused by rotating a spinning propeller, I wasn't sure about how to design the control algorithm to make it fly the airplane as I wanted. Your lecture shows me the way to analyze how it might affect the different states of the aircraft. Thank you!
AE512: I should've watched this lecture before beginning hw9! I ended up coming to the same conclusions with some of this stuff but in a more round about way.
AE 512: Sounds like you could use the eigenvector similarity transform on the B matrix to see what inputs excite which modes and use that as inputs to perform some system identification in flight/on orbit to verify the modes of the system? Instead of trying to put the vehicle in a specific state, like you said.
Hello Christopher, That was an excellent anatomy of different modes of an Aircraft and its behavior. However, I'm working on a TECS controller and I kindly request you discuss the Eigen structure assignment method on the same RCAM model to design a MIMO controller for both the directional modes which would be a great conclusion to your playlist :) Thanks and Regards Ram
Hi Ram, Thanks for reaching out. If you have questions or would like to request a video, I hope you'll consider supporting the channel via Patreon at www.patreon.com/christopherwlum. I'd love to have you as a Patron as I'm able to talk/interact personally with Patrons. Thanks for watching! -Chris
AE512: I find the discussion of short period and phugoid a little bit confusing because it sounds to me like a phugoid mode has 2 requirements: minimal damping (short duration) and long sinusoidal period. But what if you have a phugoid with a small sinusoidal period that dies out slowly? Is it still a phugoid mode?
AA516 Should the longitudinal and lateral A & B matrices be derived from Atilde(1:4, 1:4) and Btilde(5:8,5:8), or is it actually plausible for us to take A(1:4,1:4) and B(5:8,5:8) [which was shown in the video]. Thanks for the great video
AE512: If something like a slightly positive divergence eigenvalue existed for an autonomous system, would the linear controller be able to deal with it, like a pilot would? We've never looked at a case of eigenvalues with positive real parts being acceptable.
AA516: 26:54, in terms of A_long = A(1:4,1:4), is this same as Atilde(1:4,1:4)? I think A, here, is new matrix A(Atilde) because it has longitudinal states information in its(1:4,1:4). However, there are no tilde symbol in the video and lecture note(page 8), I'd like to confirm.
AE 512 - Hi Professor Lum. Any idea why I get different eigenvalues if I use Mathematica in lieu of Matlab? Eigenvalues[A] is giving me different results than [V,D] = eig(A)
Thank very much for all this wonderful content, Mr Lum. As a supporting fact what is said around minute 32 when you talk about the eigenvalues in the longitudinal decoupled system, the imaginary part of the poles gets excited when performing a bad landing. So it is usually said that if you bounce while landing you better touch and go. Otherwise a second and bigger bounce follows and in the third one the crash would be a secure fact. Nonetheless I saw very experienced pilots adding a dash of gas changing the elevator configuration to perform a satisfactory landing. Here is an example for the shake of completion: th-cam.com/video/x5ZzktAFJK4/w-d-xo.html . In 1:11:38 we can also see that delta u = -1.99 (decelariting) and delta w = 0.18 (going down), like in the landings if I'm grasping it clearly. Thanks again for the content!!!
Hi, Thanks for the kind words, I'm glad you enjoyed the video. If you find these videos helpful, I hope you'll consider supporting the channel via Patreon at www.patreon.com/christopherwlum or via the 'Thanks' button underneath the video. Given your interest in this topic, I'd love to have you a as a Patron as I'm able to talk/interact personally with all Patrons. I can also answer any questions, provide code, notes, downloads, etc. on Patreon. Thanks for watching! -Chris
A. If we had a linear feedback controller u = Kx then we would also want to look at the eigenvalues of A - BK. But here we are analyzing how the aircraft behaves with no control inputs.
AA 516 In using the modal similarity transformation to calculate a new initial condition to use for exciting the various modes, I've used x = Tz where T is the matrix of eigenvectors. However, this transformation results in a complex valued vector for me, and not a double, as expected. What is the process to get from z(0) to x(0) at 46:23?
@@ChristopherLum Currently a Part 107 remote pilot but the plan is to be a "real" pilot one day! But right now GNC is much more interesting than pilot training!
Hi, Thanks for reaching out. If you have questions or would like to request a video, I hope you'll consider supporting the channel via Patreon at www.patreon.com/christopherwlum. I'd love to have you as a Patron as I'm able to talk/interact personally with Patrons. Thanks for watching! -Chris
In case it is helpful, all my Flight Mechanics videos in a single playlist are located at th-cam.com/play/PLxdnSsBqCrrEx3A6W94sQGClk6Q4YCg-h.html. You can support this channel via Patreon at www.patreon.com/christopherwlum. Please let me know what you think in the comments. Thanks for watching!
AA516: Great explanation of the different modes! For my final, I am going to be doing the visualization. Can't wait to get it working to see them in real time!
AE512: Appreciate the visualization of the different longitudinal modes, helps to solidify what is actually going on in the state traces. Great video!
AA516: I enjoyed the visuals that you pulled up to show how the different modes looked in the simulated environment. Thanks Professor!
AA 516 - No questions, just wanted to say how cool it is to see everything tie in together from what we have been doing the entire quarter!
I know, isn't it cool how the math predicts all this real world behavior?
As always, another very helpful video! I really appreciate how your videos can distill days worth of textbook reading and cross-referencing into a single video.
Ben, thanks for the kinds words. It is always good to hear from you on TH-cam. Thanks for watching!
AA516: Finally! This is my most awaited video of this course, and it's great to see everything comes together to help build an intuitive understanding of these modes.
I'm glad it was satisfying, it has been a long journey and I agree that it is fun to see how we can leverage our past results to get to this stage.
AA516: Awesome explanation about phugoid and dutch roll modes!
AA516: Super cool how these modes can describe real life occurrences in the aircraft model!
AA516: I really enjoyed the visuals! Glad to see everything we've been learning coming together
AE512: I liked the extensive discussion on the modes. Thanks!
AA516: Great visuals with the simulator for demonstraing the different kinds of modes
AA516: Enjoyed learning about the phugoid and dutch roll modes.
AE512: Great to see the eigenvalues of the different modes and visualized on the real/imaginary plot to explain the behavior during the state traces.
AA 516: Amazing to see all the class content come together. This video has been super fascinating to watch!
I'm glad it was satisfying, it has been a long journey and I agree that it is fun to see how we can leverage our past results to get to this stage.
AA516: So cool to see everything coming together!
Bro I love u, you help me with my flight mechanics exam!
Super Interesting! I am waiting for a video explaining designing the corresponding controllers using cascaded successive loops. Great job, Prof!
Hi Ahmed,
Thanks for reaching out. If you have questions or would like to request a video, I hope you'll consider supporting the channel via Patreon at www.patreon.com/christopherwlum. I'd love to have you as a Patron as I'm able to talk/interact personally with Patrons. Thanks for watching!
-Chris
Very interesting course for basic flight mode and we would like to introduce the superior mode for the guidance and navigation
AA 516 This is such a cool lecture, you did a great job making such a complicated system intuitive for students. I have a canard pusher prop drone that I am designing in my free time and I was considering mounting the motor onto a 2-axis robot arm to make a "vector thrust propeller" to replace the rudder. However, because of the gyroscopic precession caused by rotating a spinning propeller, I wasn't sure about how to design the control algorithm to make it fly the airplane as I wanted. Your lecture shows me the way to analyze how it might affect the different states of the aircraft. Thank you!
I'm glad they are helpful, keep me posted on your project, it sounds very interesting!
AE 512: The review in the beginning helps piece all the previous videos together to form the final picture.
AA516: I was wondering how do you go about avoiding those dynamics modes, or if there are times you would even want to go into those modes?
AE512: (58:51) You should've been a speed skater!
AE512: I should've watched this lecture before beginning hw9! I ended up coming to the same conclusions with some of this stuff but in a more round about way.
AE 512: Sounds like you could use the eigenvector similarity transform on the B matrix to see what inputs excite which modes and use that as inputs to perform some system identification in flight/on orbit to verify the modes of the system? Instead of trying to put the vehicle in a specific state, like you said.
How do the eigenvalues of a fighter jet look? Are some on the RH side of a pole-zero as the instability would help with being very responsive?
Hello Christopher,
That was an excellent anatomy of different modes of an Aircraft and its behavior.
However, I'm working on a TECS controller and I kindly request you discuss the Eigen structure assignment method on the same RCAM model to design a MIMO controller for both the directional modes which would be a great conclusion to your playlist :)
Thanks and Regards
Ram
Hi Ram,
Thanks for reaching out. If you have questions or would like to request a video, I hope you'll consider supporting the channel via Patreon at www.patreon.com/christopherwlum. I'd love to have you as a Patron as I'm able to talk/interact personally with Patrons. Thanks for watching!
-Chris
AE512: I find the discussion of short period and phugoid a little bit confusing because it sounds to me like a phugoid mode has 2 requirements: minimal damping (short duration) and long sinusoidal period. But what if you have a phugoid with a small sinusoidal period that dies out slowly? Is it still a phugoid mode?
hi professor, can we apply the same concept for a fighter jet in steady level flight?
AA516 Should the longitudinal and lateral A & B matrices be derived from Atilde(1:4, 1:4) and Btilde(5:8,5:8), or is it actually plausible for us to take A(1:4,1:4) and B(5:8,5:8) [which was shown in the video]. Thanks for the great video
Kenneth, slight correction, Along = Atildle(1:4,1:4), not A(1:4,1:4). Otherwise, that is all you need to do, no derivation necessary.
Hi professor....can i use different- different controller to study further, after linearized model of RCAM
AE512: If something like a slightly positive divergence eigenvalue existed for an autonomous system, would the linear controller be able to deal with it, like a pilot would? We've never looked at a case of eigenvalues with positive real parts being acceptable.
If it is slightly in the right half place or means that it slowly grows. As such a human pilot or slow controller can handle it
AA516: 26:54, in terms of A_long = A(1:4,1:4), is this same as Atilde(1:4,1:4)? I think A, here, is new matrix A(Atilde) because it has longitudinal states information in its(1:4,1:4). However, there are no tilde symbol in the video and lecture note(page 8), I'd like to confirm.
I got the answer from the past reply:) A_long = Atilde(1:4,1:4)
AE 512 - Hi Professor Lum. Any idea why I get different eigenvalues if I use Mathematica in lieu of Matlab?
Eigenvalues[A] is giving me different results than [V,D] = eig(A)
Marcos, that sounds fishy, the eigenvalues should be the same. That being said, the ordering may be different. Can you show me at office hours?
Thank very much for all this wonderful content, Mr Lum. As a supporting fact what is said around minute 32 when you talk about the eigenvalues in the longitudinal decoupled system, the imaginary part of the poles gets excited when performing a bad landing. So it is usually said that if you bounce while landing you better touch and go. Otherwise a second and bigger bounce follows and in the third one the crash would be a secure fact. Nonetheless I saw very experienced pilots adding a dash of gas changing the elevator configuration to perform a satisfactory landing. Here is an example for the shake of completion: th-cam.com/video/x5ZzktAFJK4/w-d-xo.html .
In 1:11:38 we can also see that delta u = -1.99 (decelariting) and delta w = 0.18 (going down), like in the landings if I'm grasping it clearly.
Thanks again for the content!!!
Hi,
Thanks for the kind words, I'm glad you enjoyed the video. If you find these videos helpful, I hope you'll consider supporting the channel via Patreon at www.patreon.com/christopherwlum or via the 'Thanks' button underneath the video. Given your interest in this topic, I'd love to have you a as a Patron as I'm able to talk/interact personally with all Patrons. I can also answer any questions, provide code, notes, downloads, etc. on Patreon. Thanks for watching!
-Chris
It maybe a stupid question, but what matrix are those eigenvalues from? A, B or concatenated A and B?
A. If we had a linear feedback controller u = Kx then we would also want to look at the eigenvalues of A - BK. But here we are analyzing how the aircraft behaves with no control inputs.
AA 516 In using the modal similarity transformation to calculate a new initial condition to use for exciting the various modes, I've used x = Tz where T is the matrix of eigenvectors. However, this transformation results in a complex valued vector for me, and not a double, as expected. What is the process to get from z(0) to x(0) at 46:23?
Riley, I just saw this. Did you get it worked out?
@@ChristopherLum Yep! It helps a lot to make sure you keep the latitudinal and longitudinal vectors in the right order.
Jason-AE512: This video is a little bit more complicated than others lecture.
AE512: Would be an interesting discussion to show why imaginary values yield oscillatory Reponses in this 'real world' engineering example
AA516: 1:04:30 FAA has entered the chat lol. Control tower has a number ready for you to call haha.
You sound like a pilot :)
@@ChristopherLum Currently a Part 107 remote pilot but the plan is to be a "real" pilot one day! But right now GNC is much more interesting than pilot training!
@@rowellcastro2683Nice, I also went through the part 107 certification but as you observed, the engineering and design is much more interesting
are u aerospace engineer?
isn't it a copypaste mistake in matrix A at 22.17?
Hi,
Thanks for reaching out. If you have questions or would like to request a video, I hope you'll consider supporting the channel via Patreon at www.patreon.com/christopherwlum. I'd love to have you as a Patron as I'm able to talk/interact personally with Patrons. Thanks for watching!
-Chris
A A 516: Ojasvi Kamboj
AA516
AA516: Po