What happened to your RCS thruster system I think I saw you show off in an Everyday Astronaut video? Could that theoretically work in a situation like this?
As someone who just finished their mech eng final project that (to my own detriment) involved a truck load of ANSYS simulations, I don't envy the CFD that you ended up having to do 😂. I'll look forward to the next video with the details.
“And as always, they were mounted with about thirty pounds of hot glue” there is something profoundly wrong with this man and that is why i am subscribed to his channel
I know playing with terminal guidance is a taboo of sorts. But is it actually illegal? And how come there is so little on that topic available online outside of the US?
@@MoritzvonSchweinitzit's not illegal per se, but doing it without license is problematic and posting about it can be illegal. But that's US. It is illegal in many other countries.
Joey B out here controlling an aircraft over a WIDEEEEE envelope on his f̶i̶r̶s̶t̶ second try, and I hope ya'll know just how hard that is! Aircraft control derivatives scale with dynamic pressure (combo of airspeed and air density)... This basically means an aircraft behaves very differently at different speeds/altitudes with the same control deflection. The successful flight is a testament to Joe's math all collapsing down and "un-coupling" the rocket from its environment, from aero modeling to control system design to sensing. Next video is gonna be good! TL;DR: 😍🚀😍
Man, I'm an automation and Control engineer in Brazil, I have a masters degree in robótica and I have been teaching engineering and mechatronics for 8 years. I have no idea how on earth you deal with so many complex details in these projects. It seems like it is done for a team of 10 senior engineers. You are crazy! How do you tune the controllers before the launch? Do you have a detailed mathematical model for the whole structure? You are insane man, keep up with the work. You're going to heaven.
When you started in on canards, I started muttering "elevons". When you started talking about talking about rotation the whole fin, I nearly yelled "elevons" at the TV as well as grumbling in 737 Max overcontrol. Then when you showed your solution, I was like, DUH, elevons. Yes, I know the shuttle used a separate rudder, but honestly you should be getting the point since you had four "wings" instead of two. This is how supersonic aircraft control their flight. And if you see my name and picture, and recognize them, LONG LIVE THE PID. Glad I found your channel, we did know each other. And to really induce swearing you need to botch a Kalman filter.
It's fun seeing you go through the same problems I encountered about 15 yrs ago. I built a rocket with canard driven by high-powered rc servos. I put together a controller with an $1100 Analog Devices IMU and a custom microcontroller with SD card parameter control and data recording. I initially wanted to control roll. had 9 flights without success. At first I thought I had a control system bug, then I thought I might have a hardware problem. Finally I mechanically fixed the canard at a constant angle. I had roll reversal in every flight. I finally installed a camera to verify the data collection. Unfortunately the rocket came in ballistic and the 8 foot rocket was compressed into 8" long wad. I researched this problem and ran across a group in the NW that was having the same problem and had identified AIAA research that identified the problem many years ago.
My dad helped develop a few rockets for General Dynamics, they used something called “dithering” which made the fins vibrate(?) and when they wanted to steer in a particular direction they just made the fins spend more time on one side by interrupting the occultations, favoring the direction they wanted to go
Yah pretty sure Salvatore pais scaled this technique up to make the tic tac vehicles.. wingless UFO can only be explained via vacuum creation via high frequency vibration. Likely powered by compact fusion reactor.
Which is not a very new concept as we used similar methods for early R/C aircraft control before we came into the wonderful world of Proportional servo control, in the late 60's.😁
Nice ... use of random control noise, and then removing some randomness to influence control. Makes me wonder if the "dithering" was a technique to disrupt shockwaves traveling across the control surface.
The fins extra thickness didn't seem to be an issue, but if you do want to reduce there thickness in the future one option is to mount the servos inside the fuselage and have a thin shaft go up into the fin to control the tab. This could also allow almost all the cables to be inside the fuselage as well, further reducing drag.
Thru the whole length of the vid, one thing kept popping into mind was this: For control on the X-Y axis, a single, tapered spike on the nose, able to be pointed off-axis for 'steering'. This would eliminate downstream vortices from canards. Your tiny tabs on the back of the fins would take care of roll.
The amount you talk about how much you love making videos about this stuff is so refreshing. So many RUclipsrs get so caught up in creating content that they start to hate it, and while that isn't always controllable, I'm sure that as you grow, the donations and money from RUclips will make it possible to have access to better parts and more prototypes. Keep up the grind.
The simulations at the end are outstanding and it demonstrates how your channel not only inspires others to take on engineering projects, but perhaps even more importantly the channel builds a community of very talented aerospace engineers who come together and make meaningful contributions. Great job! Kudos to Gabriel, Matt, Andrew and Dan.
Before I finish watching the video; there is a neat trick that the first AIM-9 Sidewinder missile used to avoid needing to compensate for things like density altitude: it used force servos on the fins rather than position servos. The result is that, with a few assumptions about the center of force on the fin staying more or less the same distance behind the pivot, a given turning force on the fin created the same side force on the missile body more or less regardless of speed or altitude. The entire guidance and control system on the first marks of the AIM-9 are a fascinating cases study in how a spec project with almost no budget can force better designs.
21:15 Aside from the first couples seconds or so of this, you could've absolutely fooled me into thinking this was on-board flight footage. Well done to the community for helping here. Also would love a video on transsonic flight.
I always love the sheer attention to every detail Joe puts into everything. Everything from the rocket's functionality, the camera shots, and the video edits are all phenomenal quality. Keep up the good work.
For sure please do a video on control over transonic flight regimes! And I'd love to see one (maybe combine them) about CFD you mentioned, what specifically was the effort required to succeed, the process, and the modeling. We love the theory
transonic is really hard (it's why jetliners which have the power to exceed about 0.85 mach just don't). Best bet here is just to get through to the other side as fast as possible.
I'm 50, forced to retire last year. been doing some embedded system engineering works for more than 2 decades. Watching your videos, I have to say they made the right decision and that involuntary retirement was the best thing that has ever happened to this man. Keep up a good job as you have been! Good Luck too.
As a computer scientist, I would be interested if you could make a wind tunnel to gather enough data on the effect of the vortices and build a controller to compensate for them. No idea how hard it is to build a wind tunnel though, and I'm sure I'm underestimating the difficulty of that control problem. Good luck! Great video as always
Actually, building a supersonic wind tunnel in itself is not that difficult. Gathering the relevant amount of currency to do so, while building it in a place that is about 500 miles from your nearest neighbour........ different story.
As someone that studies Engineering Informatics (mixture of computer science and electrical engineering) I often have to work with computer science that had never heard any physics or mechanical engineering lectures and they are most times better at algorithmic and similar thinking stuff but don't let have mechanical or electronics ideas. Wind tunnel up to a couple of hundred km/h no problem use a fan big and fast enough and you are good to go. You still need to think about how to reduce the effect of the turbulance of the fan, maybe build a pull configuration the expected wind speed for the same input power is slightly slower but should still work. But now the trans and supersonic Problems. These speeds are not possible with a fan alone. And the pull configuration does nothing. If your fan is to powerfull you suck a vacuum but still don't get mach 1 and in the push configuration you still would only near to mach 1 and than produce a high preassure zone. So you need a nozzle the same type as the one on the bottom of a rocket engine. It solves the Problem of converting high pressure gas to high speed gas. BUT the gas goes from very high pressure (tens or hundreds bar (atmospheres)) to 1 bar or below every expanding gas cools down. And this kind of depressurization would lead at least to freezing water and CO2, but depending on the pressure drop even to liquid nitrogen or oxygen (unlikly in home build variants). So you don't need to start with a high pressure gas. You need to start with a high pressure high temperature gas. Problem is most materials get weaker under high temperature but the high pressure is really high so the whole thing is near its failure before you even have moving gases. Second Problem you don't want to see effects of pressure waves reflecting of the tunnel walls because that would cause similiar uncontrolable feedback loops as the canards to the fins earlier in the video. So the wind tunnel should be at least factor 5 to 10 bigger to the test object (model rocket) now we test a small model with a fin can that is only 5 cm in with (to be honest to tiny to have good estimates on how a big one would react). The wind tunnel has at least to have a diameter of 25 cm. 0.25m*0.25m*pi/4=pi/64 m² this times the desired speed of 300 m/s (yes I know speed of sound is faster under normal pressure and temperature but I will not estimate which temperature we could manage to reach in our tunnel) at 0.5 bar is pi/64 m²*300 m/s*0.5=7.36 m³/s. So you would need every second of testing 7.4 kubic meters of air delivered to your wind tunnel, forget it. This is for each second 4 full (and not the smallest ones) air bottles that divers use. Because there is no for not that rich individuals available solution that would produce this preassure and quantity of compressed gas on the fly (exeption rocket motors but they burn to hot to hold a normal test object in exhaust).
I'm working on aerodynamics of rockets myself. From what I've heard from a people who works directly with that kind of aerodynamic tunnels, just the cost of preforming a single set of tests on subsonic tunnel capable of fitting rocket this size is at minimum few thousand dollars. Not to mention building a supersonic tunnel. You can get good results just by simulations alone tho, I basicly work with that, Solidworks is a pretty good tool for obtaining such data and is extreamly easy to use. However I would questions it's results for trans sonic flows.
There is a reason for all moving fins other than extreme manouvrability. At the end of WW2 aircraft became uncontrollable due to the elevator being behind the shockwave (where it looses effectiveness) just when they were very much needed because of the onset of Mach tuck (which is a nose-down moment on the lifting surface in transonic flow). The problem of controllablility was solved on the Bell X-1 with an all moving horizontal stabilizer. On supersonic missiles this is the all moving fin. Your trim tab seems to function more as a spoiler (so to create drag) than as an aerodynamic surface to direct the airflow. It definitely gets credits for a shoestring approach. Hope you don't mind me making a suggestion: spoilers don'' t necessarily have to be in the fin section, they might as well be in the aera where you would expect the canard fins or anywhere else on the vehicle. The obvious advantage of moving the spoilers away from the fins is the available space for the servo's. Now your fins can be thin again to reduce the drag. I hope this suggestion will help you past Mach 2 and eventually into space in a controlled manner.
I was sitting here waiting for you to mention the rollerons on the sidewinder cause its like, one of my absolute favorite engineering solutions ever. So elegantly simple and yet works incredibly well Edit: im not an engineer, just a mechanic, but i think a combination of servo tabs and entirely moving fins is the way to go. This is how the trim system works on just about all modern jet aircraft. Little tab moves in opposite direction of where you want the surface to go, and generates a moment on the major surface. Allows for precise correction without having to put an enormous load on whatever you're gonna hinge the tab with. Much easier to design a fin hinge that can withstand that sort of load than a tab hinge that can. Just my $0.02 though, supersonic aerodynamics is super weird, and aviation and rocketry are only marginally similar
Im 28 years old, former police Sgt., college grad, and father of 3....I look up this man. What an inspiration you are. Weather permitting, I am about 1 week from getting my PPL as I now pursue aviation full time! Hope to meet you some day!
I've been watching your last 3-5 years of videos over the last month or two, this is pretty much the solution I've been yelling at the screen through all your roll control adventures. looking forward to the rest of the story.
You could alternatively literally make ‘ailerons’ (on aircraft wings/tails) on the bottom side of the fins if you need something a touch more commanding. Then the servo is still housed in the fins, you can use simple linkages for mechanical leveraging to use small servos with ‘big force for small movement’ and it’s simple to model, print and attach.
Maybe you need a simple analysis tool that checks all the connections are in place. ReadyToLaunch and return a green or red. Checks the values are where they should be. As you go higher with more cost then you might be glad you have this simple analyser. Good video. Keep going, you'll get there.
Is it worth simulating the glue and bumpy lumpy surface? Perhaps someone can make you a camera mount and design a groove in your rocket tube to fit the cable too. Total guess that imperfect surface might be affected by fluid dynamics at supersonic speed and above. A strong fluttering pocket of fluid could possibly move the rocker or damage it. Maybe even make it's fuel usage above calculation.
Silo launched rockets, guiding eggs to specific places on the ground, supersonic aerodynamic control, and soon to be a space shot? You are definitely on a watchlist somewhere.
Don't feel too bad, Lockheed made a very similar connector mistake on the THAAD program. Missile went about 100 yard before burying itself into the desert. The connector was to load the guidance program, but when the wires pulled out they shorted the guidance system. So, no guidance. D'oh!
Undergrad aerospace engi here. Glad to see how feedback control of dynamic systems and aerodynamics courses may be applied within a small scale in a workshop! I Hope I'd be able to construct any advanced sounding rocked before graduation inspired with your channel!
I think you bumped into the problem they had breaking the sound barrier with the oldschool split control surfaces. You've gone smart and made a teeny tiny control surface, but the split control surface becomes basically useless in the transonic region, which is why they moved to all moving control surfaces. You've probably already come to this conclusion, but if you put a teeny all moving contol surface at the tip of your fin, you'll retain control authority at speed. Having the surfaces that far out will make them more potent in roll as they have a longer lever, but hey, make smaller movements. Keep it up, it's an instant click whenever I see one of your videos!
Good show. There's also inversion layers reflecting sound and sound reflecting upwards then reflecting back down at a further distance having a bland detection somewhere between. Artillery sometimes does that.
As an Aerospace Control Engineer, this is absolutely amazing! Yes we would actually love to see more videos on control architecture and if you had implemented gain scheduling for pre and post mach flight!! Thanks a lot these video! All the best for future control missions
In the past, only a couple of objects could reach supersonic, the goal being INCREIDIBLY difficult, challenging, and made by tens of engineers, but now, even a random guy with a youtube channel can do so. How humanity advances so quickly is just too beautiful
When you asked the question i immediately thought about embedded control surfaces like on an rc airplane. I would not have immagined that small of a tab though.
I perceive through my experience of supersonic/near supersonic flight control (16 years around F-111 Avionics, :-)), your early on hunting may have been an effect of the boundary layer flow (BLF) across the fins going through changes due to the sonic transitioning shock wave generation. Once supersonic flow was stable, the roll surface could 'play' in a 'quiet' space. We had multiple static pressure sensors and localized pitots around our jet airframe that would measure Boundary layer pressure to, then help, fine tune surfaces such as flight controls but also engine inlet shaping to keep inlet air subsonic. I would suggest looking into the design changes done, over the early years, to both aileron placement along the trailing edges of wings to eliminate/minimize aileron blanking and things like spoiler tabs, etc. Also, early supersonic aircraft went from horizontal stabs w/elevator tabs, but had to switch to all moving tail planes for elevator control, as the elevators could also blank, but some of that effect had to do with the REALLY turbulent stuff coming of those wings (and their shock waves in front of the always rear mounted elevators/elevons. Definitely a lot more of a dilemma than just pointing the surface/tab where you want to 'steer'. Excellent work sir!!! 😁
Great video as always! I have one idea. Instead of going down the route of preventing the rocket / cameras from spinning, what about attaching cameras to each side of the rocket such that you get 360 degrees of coverage, then, stitch the footage together from all the cameras and un-spin it using the recorded gyro measurements during flight? You would likely need some high frame rate cameras to help avoid motion blur but from what I've seen on 360 degree videos on youtube, you can spin those puppies to your heart's content!
Supersonic flow is fascinating. I have been working on my own rocket to test control methods in a compressed flow flight envelope and can say the work you are doing is really amazing. I can't wait for the next video!
This is so cool. Nice job. One thing to remember, development prototypes do not need to be purdy... To understand what is occurring, you also need to have control position command and the PID gains. It looks like the control was saturated at times which could account for large roll displacement.
10:36 that reminds me of the stabilizer-stabilator thing with airplanes. When you have a stabilator the stabilizer is the elevator, so basically the stabilizer itself rotates the change the altitude. When you have a stabilizer, there is a separate elevator that moves on the back of the stabilizer. This is like the stabilizer.
Transonic video needs to happen for sure. Also great job on figuring this one out, I know it was a big step and took a lot of hard work. Every day you are getting closer to space and I love to see it!
Dude, I super love nerding out with you. I can pretty confidently say that every video you've already put out and all the future ones that you haven't yet made. Just do what you love. I'm pretty sure we'll all like it.
Outstanding video production Joe! Very interesting discussion on the control issues and the importance of doing good post flight analysis of what worked and what didn't.
I would watch a video titled "10 sexy tops to keep it going steady (how to prevent your missle from rolling)." Joking aside, the production value of these videos just keeps climbing- love it!
Very good, there is an italian guy who developed something similar 12 years ago. You can check his video called "Adriano Arcadipane: Roll gyro stabilized rocket with automatic control system." Aerospace Engineering
For the camera thing, instead of having it spin to counter the rotation of the rocket you could do an array of cameras all around and spice the feeds together in post to get a non moving view. I hope this made sense.
tie a pito tube to your pid loop so the fins will change their rate depending on air density / speed. having good data on the air conditions while you fly is crucial to having accurate control
It should also be noted that more modern variants of the aim-9 (namely the aim-9x as shown) does not use canards. The aim-9x uses fixed forward canards with all-moving tail fins coupled directly to thrust-vectoring fins inside of the motor nozzle.
You should look into using 2 to 4 190+ degree fisheye cameras. This way you won't need roll stabilization, because you can do very good stabilization in post, as long as the roll isn't so severe that it causes a lot of motion blur. You also don't need to make it stick out with kevlar. It can be embedded in the design. And you get to see everything from every angle in the footage.
Use 6 tabs on your final rocket. 2 for roll control, 2 for yaw, 2 for pitch. This means 2 fins will have 2 tabs and the other 2 fins will have 1 tab. When testing you could leave the yaw and pitch tabs fixed in place and test your roll stability. When you're confident about that you can start testing yaw or pitch and make sure that your roll is still stable. With this arrangement each pair of tabs is only responsible for 1 axis of freedom.
Personally I like the idea of decoupling the camera mount from the rocket. Roll stabilization is extremely well tested and successful. You dont need any active stabilization if you just use a few cameras and stitch together the footage post flight.
As a CFD guy (albeit, subsonic flows), some of the computational meshes you showed off here looked somewhat suspect to me. I'd be interested to see you go into this side of things more!
I’d use virtual canards using ducts with valves to create simulated cold gas thrusters. Been working on using this idea to make a virtual windscreen for my bike but haven’t had enough free time to really dive into it.
I feel smart! When you asked for "how would you solve this", i guessed you would integrate controllable surface into fins. I did however envision the controllable surface in the front of the fins; I wonder if the slot created by rotating the fins would have an impact on induced drag/vortex shedding since the vortexes would be close to the boundary layer on the fins and/or would the main-fin having a flow cleansing effect. Anyways...going to keep watching the rest of the video. Absolutely love how engaged I feel watching your content.
really like the third "secret" option. On subsonic aircraft, control surfaces provide better control authority than all flying surfaces and so can have lower drag in missions where lots of control is required. Supersonic airplanes usually have all moving tails to reduce wave drag.
I for one would absolutely love to see a video on the transonic region! The better I understand what problems your facing the more engaging and interesting the videos are :)
Your secret third option is what I also thought of as a logical solution after all the things you explained before coming to that, great to see we had the same thing in mind! 😄
Surely those supersonic air-to-air missiles are using all-moving fins precisely because they're supersonic. My understanding (as an armchair aerodynamicist) is that all supersonic fighters have all-moving horizontal stabs because of the phenomenon of 'control reversal' that occurs with traditional fixed stab/moving elevator control surfaces as you get to transonic speeds, which might explain your deviations in the transonic portion of the flight. Maybe you're going to cover all this in the second video? I was waiting for you to mention it here but it never came! Cool rocket through, very impressive.
When you asked the question “how would you do it” I was thinking, why not just trim tabs like an airplane or ship rudder. And while you called it secret solution of embedded canards, this is exactly what I was thinking as well.
Thanks to Incogni for sponsoring this video! To get an exclusive 60% off an annual Incogni plan, use this link: incogni.com/bpsincogni
What happened to your RCS thruster system I think I saw you show off in an Everyday Astronaut video? Could that theoretically work in a situation like this?
Looking for an intern?
I sent a email to you a email a few months back about rollerons.. nice to hear you talk about them
Please do not use scam ads.
Thumb down.
As someone who just finished their mech eng final project that (to my own detriment) involved a truck load of ANSYS simulations, I don't envy the CFD that you ended up having to do 😂. I'll look forward to the next video with the details.
Whenever you say “ should I do a video on it“ no matter what it is I immediately want to see it
Same dude, same
Aww he's a boy scout...
Its 1 page... But it exists
@@wapiti4680 ???
“And as always, they were mounted with about thirty pounds of hot glue” there is something profoundly wrong with this man and that is why i am subscribed to his channel
You could have convinced me the animation looking down along the airframe was real footage. Holy moly the little tabs work so well!
Collab????
@@reuellouwrens9853 I mean, Lafayette Systems already uses this type of control on their DIAMOND-X rocket.
collaborate, you guys.
13:07 cracked me up, i just wasn’t expecting that mouth movement
"Alright, we're BABABABA into the video..."
his sense of humor is awesome. hilarious genius!
“Supersonic aerodynamic control” is in no way the same thing as “terminal guidance” two dudes in the van out front of my house.
That's not his department. He just wants to go up.
@@ChucksSEADnDEAD wink wink nudge nudge, say no more
That's just me I'm homeless not FBI. The other guy is FBI tho and hes in my van questioning me about your RUclips comment.
I know playing with terminal guidance is a taboo of sorts. But is it actually illegal? And how come there is so little on that topic available online outside of the US?
@@MoritzvonSchweinitzit's not illegal per se, but doing it without license is problematic and posting about it can be illegal. But that's US. It is illegal in many other countries.
The neat thing about unplugging the servo on the first flight is it gave you a baseline for comparison and illustration of future flights.
Joey B out here controlling an aircraft over a WIDEEEEE envelope on his f̶i̶r̶s̶t̶ second try, and I hope ya'll know just how hard that is! Aircraft control derivatives scale with dynamic pressure (combo of airspeed and air density)... This basically means an aircraft behaves very differently at different speeds/altitudes with the same control deflection. The successful flight is a testament to Joe's math all collapsing down and "un-coupling" the rocket from its environment, from aero modeling to control system design to sensing. Next video is gonna be good! TL;DR: 😍🚀😍
Awww thank you so much dude! That means a lot :)
100% ♥ ... x-plane level engineering!
Man, I'm an automation and Control engineer in Brazil, I have a masters degree in robótica and I have been teaching engineering and mechatronics for 8 years. I have no idea how on earth you deal with so many complex details in these projects. It seems like it is done for a team of 10 senior engineers. You are crazy! How do you tune the controllers before the launch? Do you have a detailed mathematical model for the whole structure? You are insane man, keep up with the work. You're going to heaven.
JOEY B BACK WITH ANOTHER SLAMMER OF A VIDEO
🆙🆙🆙
Was that a reference to the informal nickname of the AIM-120 AMRAAM, or just a coincidence?
@@mortlet5180AGM-84 SLAM-ER
When you started in on canards, I started muttering "elevons". When you started talking about talking about rotation the whole fin, I nearly yelled "elevons" at the TV as well as grumbling in 737 Max overcontrol. Then when you showed your solution, I was like, DUH, elevons. Yes, I know the shuttle used a separate rudder, but honestly you should be getting the point since you had four "wings" instead of two. This is how supersonic aircraft control their flight.
And if you see my name and picture, and recognize them, LONG LIVE THE PID. Glad I found your channel, we did know each other. And to really induce swearing you need to botch a Kalman filter.
BPS: "The good news is we aren't doing any of that math today..."
Me: " :( "
BPS: "...That's the topic of the next video."
ME: " :) "
This. 😂
So true
Same
@@everettgihring8099 That
Don't be sad. You've got just enough time to study Quantum Field Theory before the next video.
It's fun seeing you go through the same problems I encountered about 15 yrs ago.
I built a rocket with canard driven by high-powered rc servos. I put together a controller with an $1100 Analog Devices IMU and a custom microcontroller with SD card parameter control and data recording.
I initially wanted to control roll. had 9 flights without success. At first I thought I had a control system bug, then I thought I might have a hardware problem. Finally I mechanically fixed the canard at a constant angle. I had roll reversal in every flight. I finally installed a camera to verify the data collection. Unfortunately the rocket came in ballistic and the 8 foot rocket was compressed into 8" long wad.
I researched this problem and ran across a group in the NW that was having the same problem and had identified AIAA research that identified the problem many years ago.
My dad helped develop a few rockets for General Dynamics, they used something called “dithering” which made the fins vibrate(?) and when they wanted to steer in a particular direction they just made the fins spend more time on one side by interrupting the occultations, favoring the direction they wanted to go
Yah pretty sure Salvatore pais scaled this technique up to make the tic tac vehicles.. wingless UFO can only be explained via vacuum creation via high frequency vibration. Likely powered by compact fusion reactor.
So, duty cycle control? I've seen it work with rocket motors (see: kinetic kill vehicle used for the DART) but never with fins. Interesting!
Which is not a very new concept as we used similar methods for early R/C aircraft control before we came into the wonderful world of Proportional servo control, in the late 60's.😁
@@paulholmes672, well it was the early 1960’s when he was doing it, so yeah
Nice ... use of random control noise, and then removing some randomness to influence control. Makes me wonder if the "dithering" was a technique to disrupt shockwaves traveling across the control surface.
The fins extra thickness didn't seem to be an issue, but if you do want to reduce there thickness in the future one option is to mount the servos inside the fuselage and have a thin shaft go up into the fin to control the tab.
This could also allow almost all the cables to be inside the fuselage as well, further reducing drag.
Imagine the thickness of FBI's folder on this guy
😂😂
he uses Incogni, he's safe
I think
Bro is watching his every move to insure he does not make a missile because a missile, is just a crashed rocket
Thru the whole length of the vid, one thing kept popping into mind was this: For control on the X-Y axis, a single, tapered spike on the nose, able to be pointed off-axis for 'steering'. This would eliminate downstream vortices from canards. Your tiny tabs on the back of the fins would take care of roll.
We leaving the ground with this one 🗣️🔥🔥🔥
YOU KNOW IT 🆙
we goin UP 📈
We’re going ⬆️⬆️⬆️⬆️⬆️⬆️📈📈📈📈📈📈📈📈
The amount you talk about how much you love making videos about this stuff is so refreshing. So many RUclipsrs get so caught up in creating content that they start to hate it, and while that isn't always controllable, I'm sure that as you grow, the donations and money from RUclips will make it possible to have access to better parts and more prototypes. Keep up the grind.
The simulations at the end are outstanding and it demonstrates how your channel not only inspires others to take on engineering projects, but perhaps even more importantly the channel builds a community of very talented aerospace engineers who come together and make meaningful contributions. Great job! Kudos to Gabriel, Matt, Andrew and Dan.
Before I finish watching the video; there is a neat trick that the first AIM-9 Sidewinder missile used to avoid needing to compensate for things like density altitude: it used force servos on the fins rather than position servos. The result is that, with a few assumptions about the center of force on the fin staying more or less the same distance behind the pivot, a given turning force on the fin created the same side force on the missile body more or less regardless of speed or altitude.
The entire guidance and control system on the first marks of the AIM-9 are a fascinating cases study in how a spec project with almost no budget can force better designs.
21:15 Aside from the first couples seconds or so of this, you could've absolutely fooled me into thinking this was on-board flight footage. Well done to the community for helping here. Also would love a video on transsonic flight.
I always love the sheer attention to every detail Joe puts into everything. Everything from the rocket's functionality, the camera shots, and the video edits are all phenomenal quality. Keep up the good work.
For sure please do a video on control over transonic flight regimes! And I'd love to see one (maybe combine them) about CFD you mentioned, what specifically was the effort required to succeed, the process, and the modeling. We love the theory
transonic is really hard (it's why jetliners which have the power to exceed about 0.85 mach just don't). Best bet here is just to get through to the other side as fast as possible.
I'm 50, forced to retire last year. been doing some embedded system engineering works for more than 2 decades. Watching your videos, I have to say they made the right decision and that involuntary retirement was the best thing that has ever happened to this man. Keep up a good job as you have been! Good Luck too.
"I am not proud of everything I do." is my life motto.
I hear you.
We have NO regrets.
@@glennllewellyn7369I do
Sometimes… life SUCKS and sometimes, the thing you make are… disturbing
The missile knows where it is at all times. It knows this because it knows where it isn't by subtracting where it is from where it isn't.
As a computer scientist, I would be interested if you could make a wind tunnel to gather enough data on the effect of the vortices and build a controller to compensate for them. No idea how hard it is to build a wind tunnel though, and I'm sure I'm underestimating the difficulty of that control problem. Good luck! Great video as always
The problem is that funneling air into a supersonic flow isn't exactly for the home gamer.
building a wind tunnel is actuly kind easy. building a supersonic wind tunnel however, less easy.
Actually, building a supersonic wind tunnel in itself is not that difficult. Gathering the relevant amount of currency to do so, while building it in a place that is about 500 miles from your nearest neighbour........ different story.
As someone that studies Engineering Informatics (mixture of computer science and electrical engineering) I often have to work with computer science that had never heard any physics or mechanical engineering lectures and they are most times better at algorithmic and similar thinking stuff but don't let have mechanical or electronics ideas.
Wind tunnel up to a couple of hundred km/h no problem use a fan big and fast enough and you are good to go. You still need to think about how to reduce the effect of the turbulance of the fan, maybe build a pull configuration the expected wind speed for the same input power is slightly slower but should still work.
But now the trans and supersonic Problems. These speeds are not possible with a fan alone. And the pull configuration does nothing. If your fan is to powerfull you suck a vacuum but still don't get mach 1 and in the push configuration you still would only near to mach 1 and than produce a high preassure zone. So you need a nozzle the same type as the one on the bottom of a rocket engine. It solves the Problem of converting high pressure gas to high speed gas. BUT the gas goes from very high pressure (tens or hundreds bar (atmospheres)) to 1 bar or below every expanding gas cools down. And this kind of depressurization would lead at least to freezing water and CO2, but depending on the pressure drop even to liquid nitrogen or oxygen (unlikly in home build variants). So you don't need to start with a high pressure gas. You need to start with a high pressure high temperature gas. Problem is most materials get weaker under high temperature but the high pressure is really high so the whole thing is near its failure before you even have moving gases.
Second Problem you don't want to see effects of pressure waves reflecting of the tunnel walls because that would cause similiar uncontrolable feedback loops as the canards to the fins earlier in the video. So the wind tunnel should be at least factor 5 to 10 bigger to the test object (model rocket) now we test a small model with a fin can that is only 5 cm in with (to be honest to tiny to have good estimates on how a big one would react). The wind tunnel has at least to have a diameter of 25 cm. 0.25m*0.25m*pi/4=pi/64 m² this times the desired speed of 300 m/s (yes I know speed of sound is faster under normal pressure and temperature but I will not estimate which temperature we could manage to reach in our tunnel) at 0.5 bar is pi/64 m²*300 m/s*0.5=7.36 m³/s. So you would need every second of testing 7.4 kubic meters of air delivered to your wind tunnel, forget it. This is for each second 4 full (and not the smallest ones) air bottles that divers use. Because there is no for not that rich individuals available solution that would produce this preassure and quantity of compressed gas on the fly (exeption rocket motors but they burn to hot to hold a normal test object in exhaust).
I'm working on aerodynamics of rockets myself. From what I've heard from a people who works directly with that kind of aerodynamic tunnels, just the cost of preforming a single set of tests on subsonic tunnel capable of fitting rocket this size is at minimum few thousand dollars. Not to mention building a supersonic tunnel.
You can get good results just by simulations alone tho, I basicly work with that, Solidworks is a pretty good tool for obtaining such data and is extreamly easy to use. However I would questions it's results for trans sonic flows.
There is a reason for all moving fins other than extreme manouvrability. At the end of WW2 aircraft became uncontrollable due to the elevator being behind the shockwave (where it looses effectiveness) just when they were very much needed because of the onset of Mach tuck (which is a nose-down moment on the lifting surface in transonic flow). The problem of controllablility was solved on the Bell X-1 with an all moving horizontal stabilizer. On supersonic missiles this is the all moving fin. Your trim tab seems to function more as a spoiler (so to create drag) than as an aerodynamic surface to direct the airflow. It definitely gets credits for a shoestring approach. Hope you don't mind me making a suggestion: spoilers don'' t necessarily have to be in the fin section, they might as well be in the aera where you would expect the canard fins or anywhere else on the vehicle. The obvious advantage of moving the spoilers away from the fins is the available space for the servo's. Now your fins can be thin again to reduce the drag. I hope this suggestion will help you past Mach 2 and eventually into space in a controlled manner.
15:15 🤣🤣🤣🤣🤣. I'm very glad for your sake that you got that on camera!
I was sitting here waiting for you to mention the rollerons on the sidewinder cause its like, one of my absolute favorite engineering solutions ever. So elegantly simple and yet works incredibly well
Edit: im not an engineer, just a mechanic, but i think a combination of servo tabs and entirely moving fins is the way to go. This is how the trim system works on just about all modern jet aircraft. Little tab moves in opposite direction of where you want the surface to go, and generates a moment on the major surface. Allows for precise correction without having to put an enormous load on whatever you're gonna hinge the tab with. Much easier to design a fin hinge that can withstand that sort of load than a tab hinge that can. Just my $0.02 though, supersonic aerodynamics is super weird, and aviation and rocketry are only marginally similar
joey out here innovating cost-effective aerospace telemetry and guidance solutions with servo-in-wing-tabs
Im 28 years old, former police Sgt., college grad, and father of 3....I look up this man. What an inspiration you are. Weather permitting, I am about 1 week from getting my PPL as I now pursue aviation full time! Hope to meet you some day!
I've been watching your last 3-5 years of videos over the last month or two, this is pretty much the solution I've been yelling at the screen through all your roll control adventures. looking forward to the rest of the story.
You could alternatively literally make ‘ailerons’ (on aircraft wings/tails) on the bottom side of the fins if you need something a touch more commanding. Then the servo is still housed in the fins, you can use simple linkages for mechanical leveraging to use small servos with ‘big force for small movement’ and it’s simple to model, print and attach.
I just watched past where you’re asking for help💀😂
You’re both a good rocket scientist and also a good storyteller
Maybe you need a simple analysis tool that checks all the connections are in place. ReadyToLaunch and return a green or red. Checks the values are where they should be.
As you go higher with more cost then you might be glad you have this simple analyser.
Good video. Keep going, you'll get there.
Is it worth simulating the glue and bumpy lumpy surface?
Perhaps someone can make you a camera mount and design a groove in your rocket tube to fit the cable too.
Total guess that imperfect surface might be affected by fluid dynamics at supersonic speed and above. A strong fluttering pocket of fluid could possibly move the rocker or damage it. Maybe even make it's fuel usage above calculation.
We leavin the earths atmosphere with this one 🗣️ 🔥🔥🔥
Silo launched rockets, guiding eggs to specific places on the ground, supersonic aerodynamic control, and soon to be a space shot? You are definitely on a watchlist somewhere.
I love watching the process over the years
Don't feel too bad, Lockheed made a very similar connector mistake on the THAAD program. Missile went about 100 yard before burying itself into the desert. The connector was to load the guidance program, but when the wires pulled out they shorted the guidance system. So, no guidance. D'oh!
This edit hits different! Loving it 💯
KEG ROCKET NO WAY, bro can you please tell me if your gonna keep uploading in RUclips I need to know!, I’m a big fan bro!
So excited for your project!
Undergrad aerospace engi here. Glad to see how feedback control of dynamic systems and aerodynamics courses may be applied within a small scale in a workshop! I Hope I'd be able to construct any advanced sounding rocked before graduation inspired with your channel!
I think you bumped into the problem they had breaking the sound barrier with the oldschool split control surfaces. You've gone smart and made a teeny tiny control surface, but the split control surface becomes basically useless in the transonic region, which is why they moved to all moving control surfaces.
You've probably already come to this conclusion, but if you put a teeny all moving contol surface at the tip of your fin, you'll retain control authority at speed. Having the surfaces that far out will make them more potent in roll as they have a longer lever, but hey, make smaller movements.
Keep it up, it's an instant click whenever I see one of your videos!
Good show. There's also inversion layers reflecting sound and sound reflecting upwards then reflecting back down at a further distance having a bland detection somewhere between. Artillery sometimes does that.
There’s nothing better than trigonometry
REAL
What about laminar flow?
😮😭
*Quadratic Equations left the chat*
there is one and it is called calculus
@@Physicsguy-r7k Hell yeahh calculus the GOAT
those visual representations of the camera data are nothing short of absolutely incredible! Man, that is exceptional work. Bravo all.
19:36 They are nice graphs. What software is it in?
As an Aerospace Control Engineer, this is absolutely amazing! Yes we would actually love to see more videos on control architecture and if you had implemented gain scheduling for pre and post mach flight!!
Thanks a lot these video! All the best for future control missions
I am 13 year old boy. You have truly inspired me to pursue my passion in rocketry.
Be prepared for lots of failure, and you best damn well make sure you get up and try again. Do. Not. Give. Up.
Me too I was 12 when I saw this guy and now I’m 16 sending my first high power rocket
@darkmetal20 Me too!!! I already tried to build a sugar - kno3 rocket but it failed
This summer I will try again!
Internet safety: 📉📉📉
That telemetry video simulation is super impressive. I love the amount of data collected and the effort taken to reenact the flight video.
BRO ITS YHE GUY BEPIS JOHN OUT HERE ROCKET? a good start to the day :)
I love all the positive on subject comments here, so nice to see from real space enthusiasts.
What awesome work, keep it going from the UK.
Joseph bizzlington back with actual missiles now 😂
In the past, only a couple of objects could reach supersonic, the goal being INCREIDIBLY difficult, challenging, and made by tens of engineers, but now, even a random guy with a youtube channel can do so. How humanity advances so quickly is just too beautiful
20:04 i want that video
When you asked the question i immediately thought about embedded control surfaces like on an rc airplane. I would not have immagined that small of a tab though.
> "Switched over to fancier onboard cameras, GoPros"
> 2 minutes later
> "None of the GoPros worked"
You got the full GoPro experience
You do all this to put something in orbit is something. You do it for the latter ,and filming for entertainment is something++ . Bravo
YES HE UPLOADED
Bro I love been checking like once a day for like 3 months
@@JackDalfino I just turn on notifications
We are all excited but why are you yelling?
@@dr4d1swhy are you so mad, and I’m not yelling dumbass 💀
I perceive through my experience of supersonic/near supersonic flight control (16 years around F-111 Avionics, :-)), your early on hunting may have been an effect of the boundary layer flow (BLF) across the fins going through changes due to the sonic transitioning shock wave generation. Once supersonic flow was stable, the roll surface could 'play' in a 'quiet' space. We had multiple static pressure sensors and localized pitots around our jet airframe that would measure Boundary layer pressure to, then help, fine tune surfaces such as flight controls but also engine inlet shaping to keep inlet air subsonic. I would suggest looking into the design changes done, over the early years, to both aileron placement along the trailing edges of wings to eliminate/minimize aileron blanking and things like spoiler tabs, etc. Also, early supersonic aircraft went from horizontal stabs w/elevator tabs, but had to switch to all moving tail planes for elevator control, as the elevators could also blank, but some of that effect had to do with the REALLY turbulent stuff coming of those wings (and their shock waves in front of the always rear mounted elevators/elevons. Definitely a lot more of a dilemma than just pointing the surface/tab where you want to 'steer'. Excellent work sir!!! 😁
AIM 120 AMRAAM has left the chat
Great video as always! I have one idea. Instead of going down the route of preventing the rocket / cameras from spinning, what about attaching cameras to each side of the rocket such that you get 360 degrees of coverage, then, stitch the footage together from all the cameras and un-spin it using the recorded gyro measurements during flight? You would likely need some high frame rate cameras to help avoid motion blur but from what I've seen on 360 degree videos on youtube, you can spin those puppies to your heart's content!
STOP MOVING THE GRAPHS!
MOVE THE GRAPHS!
EAT THE GRAPHS!
@@gamerbossharmonFUCK THE GRAPHS!
Supersonic flow is fascinating. I have been working on my own rocket to test control methods in a compressed flow flight envelope and can say the work you are doing is really amazing. I can't wait for the next video!
Man just discovered the power of the trim tab! Very cool
he looks exactly like elon musk
Ikr😂
lmao elon needs to see this🤣
Wow, I knew roll required less force to control but the effect you get from small motions of such a small tab is mad!
This is so cool. Nice job. One thing to remember, development prototypes do not need to be purdy...
To understand what is occurring, you also need to have control position command and the PID gains. It looks like the control was saturated at times which could account for large roll displacement.
10:36 that reminds me of the stabilizer-stabilator thing with airplanes. When you have a stabilator the stabilizer is the elevator, so basically the stabilizer itself rotates the change the altitude. When you have a stabilizer, there is a separate elevator that moves on the back of the stabilizer. This is like the stabilizer.
Transonic video needs to happen for sure. Also great job on figuring this one out, I know it was a big step and took a lot of hard work. Every day you are getting closer to space and I love to see it!
Thanks! An awesome video, I just loved model rockets when I was a kid. Turned that into a EE/computer programmer.
This is crazy how that little servo has given you so much control of that rocket!
That red curve...always speechless watching your videos. Such a brilliant young man.
You are the perfect mix of youtuber and engineer, these videos are great and inspire people. Thank you... can't wait for the math video :)
Dude, I super love nerding out with you. I can pretty confidently say that every video you've already put out and all the future ones that you haven't yet made. Just do what you love. I'm pretty sure we'll all like it.
"Thrust vectoring was just easier with fins"
Insane lol. Very impressive stuff.
Being in the FPV quad scene has told me one thing about GoPros: the newer they are the less rugged they got and the more easily I've seen them fail.
Outstanding video production Joe! Very interesting discussion on the control issues and the importance of doing good post flight analysis of what worked and what didn't.
I would watch a video titled "10 sexy tops to keep it going steady (how to prevent your missle from rolling)." Joking aside, the production value of these videos just keeps climbing- love it!
Very good, there is an italian guy who developed something similar 12 years ago. You can check his video called "Adriano Arcadipane: Roll gyro stabilized rocket with automatic control system." Aerospace Engineering
For the camera thing, instead of having it spin to counter the rotation of the rocket you could do an array of cameras all around and spice the feeds together in post to get a non moving view. I hope this made sense.
tie a pito tube to your pid loop so the fins will change their rate depending on air density / speed. having good data on the air conditions while you fly is crucial to having accurate control
It should also be noted that more modern variants of the aim-9 (namely the aim-9x as shown) does not use canards. The aim-9x uses fixed forward canards with all-moving tail fins coupled directly to thrust-vectoring fins inside of the motor nozzle.
I definitely would be interested in video(s) about the transonic regime. Not to mention subsonic/supersonic/hypersonic
You should look into using 2 to 4 190+ degree fisheye cameras. This way you won't need roll stabilization, because you can do very good stabilization in post, as long as the roll isn't so severe that it causes a lot of motion blur. You also don't need to make it stick out with kevlar. It can be embedded in the design. And you get to see everything from every angle in the footage.
Use 6 tabs on your final rocket. 2 for roll control, 2 for yaw, 2 for pitch. This means 2 fins will have 2 tabs and the other 2 fins will have 1 tab. When testing you could leave the yaw and pitch tabs fixed in place and test your roll stability. When you're confident about that you can start testing yaw or pitch and make sure that your roll is still stable. With this arrangement each pair of tabs is only responsible for 1 axis of freedom.
Gabriel Yamato is the best when we talk about simulations with Ansys. Tu é foda!
Personally I like the idea of decoupling the camera mount from the rocket. Roll stabilization is extremely well tested and successful. You dont need any active stabilization if you just use a few cameras and stitch together the footage post flight.
Yes please: I’d love a discussion on the difficulties with the transonic region!
As a CFD guy (albeit, subsonic flows), some of the computational meshes you showed off here looked somewhat suspect to me. I'd be interested to see you go into this side of things more!
I’d use virtual canards using ducts with valves to create simulated cold gas thrusters. Been working on using this idea to make a virtual windscreen for my bike but haven’t had enough free time to really dive into it.
Great job Gabriel, thanks for your contribution using Ansys STK simulation SW.
I feel smart! When you asked for "how would you solve this", i guessed you would integrate controllable surface into fins. I did however envision the controllable surface in the front of the fins; I wonder if the slot created by rotating the fins would have an impact on induced drag/vortex shedding since the vortexes would be close to the boundary layer on the fins and/or would the main-fin having a flow cleansing effect. Anyways...going to keep watching the rest of the video. Absolutely love how engaged I feel watching your content.
really like the third "secret" option. On subsonic aircraft, control surfaces provide better control authority than all flying surfaces and so can have lower drag in missions where lots of control is required. Supersonic airplanes usually have all moving tails to reduce wave drag.
I for one would absolutely love to see a video on the transonic region!
The better I understand what problems your facing the more engaging and interesting the videos are :)
Your secret third option is what I also thought of as a logical solution after all the things you explained before coming to that, great to see we had the same thing in mind! 😄
Surely those supersonic air-to-air missiles are using all-moving fins precisely because they're supersonic. My understanding (as an armchair aerodynamicist) is that all supersonic fighters have all-moving horizontal stabs because of the phenomenon of 'control reversal' that occurs with traditional fixed stab/moving elevator control surfaces as you get to transonic speeds, which might explain your deviations in the transonic portion of the flight. Maybe you're going to cover all this in the second video? I was waiting for you to mention it here but it never came! Cool rocket through, very impressive.
When you asked the question “how would you do it” I was thinking, why not just trim tabs like an airplane or ship rudder.
And while you called it secret solution of embedded canards, this is exactly what I was thinking as well.
That's awesome, Joe! I'm so chuffed for you. What an incredible accomplishment!