Can a satellite do a yo-yo trick?

[@RealEngineering]

Just found your channel. Love it!

[@PracticalEngineeringChannel]

+Real Engineering Thanks!

[@leonardochavez1144]

me too!

[@peterelliotpeter]

+Practical Engineering same!

[@roridev]

Real and Practical Engineering . Let the fusing begins.

[@haph2087]

LoliDEV I’ve been watching both for a while now.

[@markevans5127]

"....except at the end, you get your arms cut off!" That made me laugh. Great video and explanations.

[@denzvenvadakkan5103]

5:43🤣🤣🤣🤣🤣

[@Mozifyyourknowledge]

Old scored oldfi

[@tophersplat]

Did the same thing!

[@theCodyReeder]

I actually had a problem with this stalling a pump I was designing as I would pump the liquid out with the centrifuge effect the pump would rapidly slam to a stop as all the energy got used up moving the liquid outward. The solution of course was MOR POWAR!

[@PracticalEngineeringChannel]

+Cody'sLab of course!

[@iaago1520]

Cody'sLab have you ever played ksp??

[@iaago1520]

Practical Engineering you just earned a sub

[@josefl.2053]

CLAAAARRRRKKKSOOOOONNN

[@crackmyknuckles169]

Sure is Clarkson in here...

[@bryanpotts5594]

Bloody hell. I've known about spin stabilization for a long time. But I've never thought about the method of stopping the rotation. This method is absolutely brilliant.

[@listtamaru]

Coming back to this video several months after I watched it for the first time. Since Febryary I've been studying moment of inertia and its polar version, but hadn't yet clicked on my brain what they actually mean. Nothing that a smart video along with some coffee and cake couldn't clarify. Thank you 3000!

[@PierreAnkh]

I think KSP makes people interested in engineering so it's great to have this kind of channel to help with our hunger for science knowledge ! Great video and great job, thank you !

[@PracticalEngineeringChannel]

+Ankh Thanks!

[@tensevo]

I love how we hold "rocket science" in such high regard, ...when they litter more than anybody. If it's not solid rocket booster, or thermal insulation, it's abandoned satellites, road cars, or yo-yo despin masses.

[@AppliedScience]

Great demo!

[@PracticalEngineeringChannel]

+Applied Science Thanks Ben!

[@Art-fn7ns]

That awkward moment when I realized that Applied Science and Practical Engineering are actually 2 independent channels 😊

[@kcwidman]

This might be my new favorite channel. I just finished AP physics 1 in high school which gives me just enough knowledge to actually understand everything that is going on.

[@morte3252]

Use magnetic turning. Set 3 coils perpendicular to each other, apply proper amount of current individually, and the satellite can be oriented at any angle you want.

[@AnonymousFreakYT]

"Except at the end you get your arms cut off." Best rocket science line ever!

[@wgoulding]

This is used on a lot of spin stabilized solid rocket upper stages, as most lower stages use fins for stabilization. Liquid fuel stages are almost always controlled by vectoring the thrust in a slightly different direction using gimbals, or employ smaller thrusters that are either used for control or can themselves be vectored. If a liquid stage was spin stabilized, the fuel would stick to the sides of the tank and you wouldn't be able to use all of it, which is a huge no no. The short clip you have at 5:38 is the Payload Assist Module boosting the Phoenix lander into a Hohmann transfer to Mars, and it is a solid fuel upper stage.

[@hdavidritscher3774]

I believe that this is exactly what happens with light. The further it travels in space the more it slows down and the wavelength becomes longer. Many scientist believe that the stars and galaxies are moving away from each other because of the Doppler Effect from the light. But this could also be explained by the Yo Yo De-spin. Light De-spin could require millions of years to become noticeable, but it could account for the red shift from distant galaxies. So the galaxies may not be moving away from each other as fast as has been claimed. Just a thought.

[@Wanted_Tiger]

the physics and dynamics don't get to my head without a good video with a good explanation ,i learn faster like this instead of the old way as books , great work man.

[@mehmetedex]

This made me a subscriber. I probably watched over a billion youtube video about engineering since 2009 and never seen one as influencial as this one. Thank you sir.

[@Milchmann2]

Jesus Christ that video is awesome. Super easy to understand explanation. I should try to build my own yoyo system. I also love that you give your resources on your blog!

[@Cheticus]

beautiful model of the classic yoyo despin. I love your quick release mechanism. thank you for this!

[@jeffhaskin895]

Can I just say that you really *look* like an engineer. I appreciate the commitment to the brand.

[@majortom4543]

I honestly thought by the title of this video that it was going to be a bullshit video by some youtuber who invents stuff to get more views but wow, im glad i still watched it, i knew the trick about the figure skating thing but i didnt know it was applied on rockets, im glad i found this channel, im going to smash that like button and the subscribe as well, i also saw the video of the reinforced dirt, keep up the great work.

[@fyermind]

Here from your work on Tom Scott's Channel. This is amazing stuff you're doing. Perfect for a day when the roads are shut down by snow.

[@lLonginuss]

This was really cool. Things I never knew existed, and also seeing how effective such a small weight can be. Your videos are awesome, please keep making more!

[@vovovovan]

I've discovered your channel recently and just can't stop watching it. I am an aeronautical engineer by background, and can apply a lot of these to my education. Absolutely love your videos, hopefully they inspire kids to become engineers.

[@PracticalEngineeringChannel]

Thanks! That's really nice!

[@aaronrenfroe5199]

Dude this is awesome. You just taught a space geek something new. That's rare for me these days.

[@Fuchswinter]

Not sure why I only found this video now, I think I watched most of your infrastructure videos by now. Thank you for explaining things so clearly for laypeople

[@SvetlinTotev]

You know someone's a good engineer when you see him play KSP :D

[@werderdley245]

The tethering trick is so ingenious. Makes you appreciate the capabilities of scientists c:

[@MrEazyE357]

Keep making cool stuff Grady! Why you don't have more subs is beyond me. Just know that the ones you do have REALLY appreciate what you're doing. Thank you!

[@Taytyaaytyat]

"except at the end you get your arms cut off" oh man you are good

[@MichaelNatrin]

Great video and demonstration. Better than textbooks and college professors.

[@Cactusworkshopchannel]

Excellent explanation and video. It all fell into place. thanks for another great episode!

[@nolan8377]

More satellite/rocket videos! I loved this one.

[@LucidTrucido]

Very cool video Grady! I really liked how you brought together the simple concepts (such as the torque bolt) from the start of the video into the construction of the model at the end.

[@roxchang8293]

That was fantastic. Great visualizations and demonstrations throughout the video.

[@frankthedrugmule8294]

This is the best explanation/demonstration of anything I've ever seen. You have a gift. Subscribed

[@PracticalEngineeringChannel]

+Frank TheDrugMule Thanks!

[@rionmotley2514]

I was honest-to-god trying to explain this to someone the other day and couldn't for the life of me find my Elements of Space Technology book to throw at them. *high five* on the timing. ;)

[@AEastrolabe]

Great video with a very clear explanation ! Came here from the KSP subreddit : it's so great to see the game used to demonstrate your claims. I may try that too in the future.

[@mikestoneadfjgs]

Very interesting video. I was on a design team for one of those CubeSats and instead of stabilizing a uniaxial spin we had to stabilize it from a full tumble. We used a designed a gravity boom and 3 low power reaction wheels to bring the satellite within .05 degree rotation per couple hundred orbits. I had no idea that this method was used for larger space equipment!

[@jacoboopy9150]

I love your use of algodoo! I've been using algodoo for a while now, to demonstrate some concepts to my family and friends, and to make prototypes of my own ideas! It's such a great way to visualise what's going on, even with complicated mechanisms and forces. Keep the videos coming!

[@sagiksp4979]

Thank you, /r/KerbalSpaceProgram, for bringing me here

[@contentdeleted2319]

me too

[@lucacapperucci8711]

Ha

[@NapoleChan]

Also due to Randy Dobson's KSP yo-yo despin video.

[@doxielain2231]

Kerbal Space Program brought me here, and now I shall stay for the excellent demonstration and explanation. Thanks!

[@MegaWiiFan]

Great video! Astonishing how these simple principles can be applied to solve huge problems.

[@JayLikesLasers]

I'd love to hear more about rocket engineering/orbital mechanics.

[@macdjord]

Neat! I knew about yo-yo despin already, but I'd always assumed they let the masses out gradually allowing the spacecraft to reach a steady state with the masses fully extended before cutting them loose, then cancelled out the residual slow spin with RCS or gyros. I didn't know you could let the masses snap forward to completely cancel spin like that!

[@merlinjanoras9157]

You're one of the youtubers whose every video is worth liking. Keep up the good work.

[@Rebecca-zr2zx]

Love that you make this easy to understand. I never knew how they stopped those satellites from spinning! Thanks, great video.

[@CalvinoBear]

Loving these videos. It's great how you not only talk about a cool engineering problem, but you actually build a model that not only shows the solution to the problem, but that often it can be done without massive budgets. So cool! Maybe you could build a control moment gyroscope next...

[@locohombre79]

Everything since the rebrand has been fantastic but this takes the cake

[@PracticalEngineeringChannel]

+locohombre79 Glad to hear it!

[@daviddupoise6443]

Sir Isaac would be proud; as he should be. I love this channel.

[@dt28469]

Kerbal Space Program and Algodoo! nice. I love both of those

[@encellon]

Excellent summary. There are three more major impediments ...1) Assuming workable materials, there's the practical problem of assembly -- how to actually put the thing in place, 2) Costs that are likely in the hundreds of billions (or more), and 3) Random space junk and active satellites ready to slice the cable within weeks or months of its emplacement (a 100% no-hand-waving show-stopper).

[@ProstetnicVogonJeltz]

Fantastic stuff! A solution to a problem I never even knew existed, simply explained. Very well done sir!

[@justinfiaschetti]

awesome video!! i am 17 and a junior taking AP physics at my high school. we just finished up the torque unit so this video was perfect timing!! its nice to see the stuff i learned in the classroom have real world applications.

[@festerbestertester2232]

Great video - you've found a way to explain a complex problem at a level that my 11 year old son can understand and now he's juiced to build his next rocket. Thanks for this.

[@PracticalEngineeringChannel]

+Fester Bestertester So happy to hear this. Thanks!

[@MarkChapnell]

I wish I'd had you as a science teacher at school. so well explained I took it all in

[@ugasmallsatlab1120]

Great video! I have actually worked at NASA on the Orion project and we have engineers at our Small Sat Lab who love this video! Great channel - keep it up!

[@PracticalEngineeringChannel]

+UGASmallSatLab Very cool! Thanks!

[@mikechu01]

This aggravates my Kessler Syndrome.

[@Sander_Datema]

The weights will brobably be in a low orbit or an elliptic one that intercepts the atmosphere. In either case, the orbit will decay quickly due to drag.

[@gavinjenkins899]

Sander Datema There's not going to be enough precision to guarantee that in what is intentionally a dumb, low tech system. If you got extremely lucky and happened to release them perfectly radial and antiradial, maybe (even then only if you're doing this in very low orbit), but if you screw up the timing by a tiny fraction of a second, then you end up releasing them normal and antinormal, then they will remain at the same altitude you are at, just as circular, but simply with different inclinations, and could even come back and hit the same ship that released them...

[@Buddie21341255612351]

Would they fall back to earth if you release them in suborbital trajectory (speed), and after that you can burn yourself to an orbital flight

[@adamfra64]

@@Sander_Datema just lithobrake.

[@eeelmane]

this channels great i dont think you need fancy animations the practical examples you make are far better

[@alexbv475]

Algodoo and kerbal space program, + engineering, i think i found a new channel to watch.

[@GlennHamblin]

Another great simple demonstration. Thanks Grady.

[@franktoffel]

Just discovered your channel! Engineering, prototypes, arduino, simulations... love it!

[@PracticalEngineeringChannel]

+Franz Navarro Glad to hear it!

[@spdecoy]

this demo is really great. makes me want to build one just to give it a try and experiment with lengths and timing.

[@DenysVitali]

Really great home made realization! congrats!

[@stefanstoian6196]

This was a great video!Keep making videos on aerospace engineering. I really love your style.

[@CheeseWithMold]

I LOVE LOVE LOVE these types of videos! It would be absolutely amazing if you can make more videos based off of concepts in aerospace engineering! Especially in the style that you have done this one in!! But did you really have to bring back bad memories of CRS-7? :P

[@theSuitMusic]

This is one of those channels you just binge-watch until you're starved for more. Great stuff!

[@nelumbonucifera7537]

Another great video. You do a great job making these concepts approachable. Combining simulations and physical models really brings it home.

[@MGOCinema]

Really well explained and I loved the physical examples.

[@Daniel_D_556]

Plus one for KSP examples. Jeb would be proud!

[@briangingerich7632]

Awsome, very informative, my son has taken a rocket project in 4-h for three years now and this will help him add to it!

[@brindians]

Very informative. Worth every minute. Thanks a lot for making such videos.

[@RandomGuy0987]

Hmm that yo yo despin method for spacecraft seems so obvious in hindsight but I've never heard about it before this video. Nice.

[@waltherbert]

I like that you show equations with your videos. Also, the software you have access to makes for some great video and easy to understand visuals. Thanks for posting! Keep it up please.

[@PracticalEngineeringChannel]

+Walt Herbert Thanks! The only software I used was Algodoo (free) and Kerbal Space Program which is a video game. :)

[@hiphopanonymous9859]

You took way too long to get to the point but when you finally did you did it well.

[@movax20h]

Interesting. Never realized that just that small amount of mass is needed to achieve so big change in rotation. I always was thinking more is needed, and that would make it impractical. But it is a function of mass and length of the tethers, and these can be easily and cheaply controlled.

[@markbroome2187]

first video I watched and probably the first account I've ever subbed to after a single video. Keep it up, please.

[@ziknik7795]

I had the same thought about space junk that you mentioned near the end of the video about halfway through myself. However, I think it wouldn't be too problematic to use the yoyo de-spin shortly after exiting atmosphere, but before achieving an orbit. This would allow the masses to fall back into atmosphere and presumably be eaten away by ablation. This puts you back in the same problem you had before, which is being at the mercy of small imbalances in your craft, but once out of the atmosphere my understanding is that the avionics would be capable of counteracting the forces using angular velocity sensors and maneuvering thrusters, which have limited efficiency in atmosphere. A fringe benefit of not madly spinning about.

[@MinecraftAddict32]

Keep it up man. Im new but the amount of work you put in your videos is not going unnoticed. With such quality you will see a random spike in subscribers some day. Best of luck, and thank you for teaching me something new.

[@nolan20expert]

R.I.P. all the kerbals who perished in his demonstrations. Your sacrifice will not be forgotten

[@Fungamerplays]

THANK YOU! I have always been wondering what these strings are that the spacecrafts release after the burn!

[@MegaKilt]

Oh no. I have an exam in mechanics tomorrow morning. I was trying to relax, not obsess over the radius of gyration of that blob.

[@george27121984]

That's very very simple and clever. Nice video. Great!

[@Sander_Datema]

Looks like you've reached the awesome KSP community. That should get you some subscribers.

[@nuttynathan]

This is the first video I've seen on this channel. Awesome stuff. I'll be back for more! Also, cool build!

[@brandongaines1731]

Dang, you've come a long way since these early videos! Love this channel, keep up the good work!

[@BrianSu]

this is why ballet dancers move their limbs away from their core while spinning to slow down and vice versa.

[@GroovyVideo2]

saw despin on a satellite vid a few days ago - good explanation how it works -Thanks

[@andrewsobotka]

Very cool video. Great explanation!

[@chawkzero]

Fantastic video! Please make more stuff. Make a video about ALL the engineering things!

[@thecosmy1]

so we could technically stop earth from spinning ?

[@PracticalEngineeringChannel]

Give me a long enough tethered mass and a big enough quick-release mechanism... ;)

[@pabloraez767]

It´s not the best thing to do tho X)

[@Sander_Datema]

Problem: gravity. The centrifugal force isn´t strong enough...

[@allanrichardson1468]

We do have quite a few yoyos we don't need! LOL But why would you want to stop its spinning anyway?

[@99wins]

The problem would be that when we release the mechanisms, nothing would happen. Even though the earth is spinning, its like magic that this actually wouldn't work. It is the same magic that keeps the moon inside earths orbit and not get sucked into the suns orbit and all the other planets. Nasa told me so.

[@PaulgoesFibo]

I love it Grady!

[@zulucharlie5244]

Outstanding tutorial!! Great job!

[@bratislavpetkovic929]

hey small idea! just repeat the process of extending the weights once the top starts to spin the other way

[@gregknipe8772]

excellent. thank you. enjoy digging back into your archive.

[@actiontom]

This reminds me figure skating, when the person spinning pull his hands to his body to spin faster. Yo-Yo trick seems to be an oposite of that.

[@AflacMan13]

"The world is full of inspiration... if you just know what direction to look." Imma need you to T-Shirt that please.

[@Happy-sk7zp]

I got to know about this Channel from INSIDER. This is the first video I've watched & I really loved it. You've explained being so simple & deeply. I've never seen such kind of simple & meaningful video. I've subscribed this channel & will feel honour to share this channel. Thanx alot for giving such beautiful knowledge to us :)

[@hjwiser]

This is great - I learn so much on your channel. Thanks for putting these videos together!

[@gregorka9]

Keep up the great work. You definitely have a gift for making these things easier to digest

[@calebburnett]

Learned something new today.

[@landynpethrus8930]

Great video. Really enjoyed it!