Exoskeleton wing design - how carbon fiber makes it possible

Ғылым және технология

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The wing of the DarkAero 1 is strong enough to support thousands of pounds of lift load while remaining exceptionally light. Part of the secret behind this is it's made from carbon fiber composite. However, there's more to its structure than meets the eye. In this video, we discuss the design of the composite structures inside the wing of the DarkAero 1 and what makes them different.
0:00 - Intro
0:18 - Design Requirements
1:51 - Lift Load Distribution Defined
2:57 - Conventional I-Beam Wing Spars
6:11 - The DarkAero "Hollow Grid" Approach
7:32 - Advantages of "Hollow Grid"
8:52 - Advantages of Using Composites
10:15 - Physically Test or Simulate?
11:40 - Summary
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Пікірлер: 328

  • @DarkAeroInc
    @DarkAeroInc Жыл бұрын

    Learn how to design and build your own high-quality composite parts and structures! Sign up for the Aerospace Composites Course here: darkaero.com/courses/aerospace-composites Online version available here: darkaero.podia.com/aerospace-composites

  • @thegoldenatlas753

    @thegoldenatlas753

    Жыл бұрын

    Im curious will yall have a jet engine variant in the future like Sonex has done?

  • @ashsmitty2244

    @ashsmitty2244

    Жыл бұрын

    We must be getting close to take off.

  • @californiadreamin8423

    @californiadreamin8423

    4 ай бұрын

    Very impressive lecture. When you performed the load testing of the complete wing, even though the wing withstood the load, how do you know if internal damage has occurred ? Do you have inspection hatches/ holes to enable say fibre optic visual inspection, or are there other NDT testing methods available….strain gauges, ultrasound etc… Inevitably the wing will experience stress/strain reversal which in an Al structure will lead to fatigue, do these composite structures delaminate ? How do you plan to verify the structural integrity while in service ?

  • @TheClearsky88
    @TheClearsky88 Жыл бұрын

    I really like your project and your videos. As a mechanical engineer myself I like your factual, no marketing bullshit approach to your videos and also to your product itself. A breath of fresh air in the "sell pie in the sky" startup world.

  • @homomorphic

    @homomorphic

    Жыл бұрын

    Haha, yeah, no battery electric powertrain. I guess the long range requirement killed that in the first 5 seconds of analysis.

  • @deldridg

    @deldridg

    Жыл бұрын

    I would agree. Engineer here too.

  • @glennlane6599
    @glennlane6599 Жыл бұрын

    I mean this as a huge compliment. In your next life you would make a fantastic Mechanical Engineering Professor. You have the rare ability to explain complex concepts in an easy to understand presentation. Thank you.

  • @cptairwolf
    @cptairwolf Жыл бұрын

    The methodology you guys practice in researching, building and testing parts is really impressive.

  • @causewaykayak
    @causewaykayak Жыл бұрын

    Yes, this team is a breath of fresh air. Let's hope they do well after all their effort.

  • @timgarrett203
    @timgarrett203 Жыл бұрын

    Extremely good and concise presentation of the right way to do wing design! Can’t wait to see her fly!

  • @xpeterson
    @xpeterson Жыл бұрын

    I was always curious about the solid foam core vs hollow composite wings. Cool to see you guys came up with your own unique solution

  • @bradley3549
    @bradley3549 Жыл бұрын

    "Structural Divergence" is suddenly my favorite way of saying the wings broke off.

  • @DarkAeroInc

    @DarkAeroInc

    Жыл бұрын

    Add to that “thermal excursion” as a way to say the airplane started on fire.

  • @daszieher
    @daszieher Жыл бұрын

    I started watching these, because I just love fast and efficient aircraft. However, these videos provide such an in-depth insight into composite manufacturing that my engineering interest now benefits more from it than my passion for flight 😄

  • @matthayward7889
    @matthayward7889 Жыл бұрын

    I can’t stop looking at that beautiful carbon fibre 😍 fascinating discussion about why you’ve made the choices you have, and how it benefits the design.

  • @bwalker4194
    @bwalker4194 Жыл бұрын

    Excellent content and presentation, guys! You all have great skill at not only highly technical processes but also the ability to convey it down to our level without coming across as condescending or droll. Congrats! keep them coming!

  • @woutermissiaen4745
    @woutermissiaen4745 Жыл бұрын

    Nice video! I'm curious to see how the fueltank works with so many compartments.

  • @Zav

    @Zav

    Жыл бұрын

    I think it's essentially gravity drain through interconnected compartments and a large reservoir between the wings to collect before sending to the engine fuel lines.

  • @ashsmitty2244

    @ashsmitty2244

    Жыл бұрын

    They act as natural baffles.

  • @divyajnana

    @divyajnana

    Жыл бұрын

    I'm with you, would like to see the fuel tank design, seems like you would need a lot more sealant, which would mean more weight.

  • @ashsmitty2244

    @ashsmitty2244

    Жыл бұрын

    @@divyajnana More sealant for what?

  • @ashsmitty2244

    @ashsmitty2244

    Жыл бұрын

    @@divyajnana Watch their videos from beginning to end and you will then know what you didn’t before. 😉

  • @Mariano.Bernacki
    @Mariano.Bernacki Жыл бұрын

    I really, really, really like that you guys are product-focused and engineering-centric. That takes care of marketing by itself, as opposed to others "sell impossible performance first, figure out how to make it close-ish enough that you are not sued later" like the Raptor fiasco.

  • @SKYHILLMIKE
    @SKYHILLMIKE Жыл бұрын

    Wow, so well explained, detailed and concise. Love the idea that you don’t need mould so you can change the design quick and easily.

  • @NeilStainton
    @NeilStainton Жыл бұрын

    Kudos. You guys are so professional and so generous with your time in sharing your knowledge and vision. If I was 40 years younger I would beg to work with you.

  • @earlgreystoke3324
    @earlgreystoke3324 Жыл бұрын

    Excellent damage tolerant design. Multiple load paths reduce the risk of single point failure. You explain complex engineering principles in a direct, easy to understand manner.

  • @doncarlson8391
    @doncarlson8391 Жыл бұрын

    Your comment about testing vs simulation is so very true and ultimately important. Simulation is only as good as the data that's entered and all too often what's thought to be complete has omissions. Empirical data from testing will fill in the simulation gaps and keep you and your passengers safe. Thanks for the video and explanation.

  • @deldridg
    @deldridg Жыл бұрын

    Great to be able to come along on your journey. Thank you for the big effort you are putting in to share your story and educate us along the way. Very exciting project! Cheers from Sydney - Dave

  • @dittilio
    @dittilio3 ай бұрын

    Damn your white board drawing/writing skills are good. Aesthetics for days.

  • @aaronkaufmann2242
    @aaronkaufmann2242 Жыл бұрын

    On the manufacturing topic, could you give us some insight into how the hollow grid is bonded to the skin? Specifically how you can count on that in a tank application.. Love these videos, incredible content. Great job guys!!!

  • @JasonKuehn

    @JasonKuehn

    Жыл бұрын

    Agreed, love the innovative ideas and think this is brilliant for things like control surfaces. But have to admit I am skeptical of that being used as a tank. There is a whole lot of bond area there and if any bit of it fails it will both leak and be inaccessible for repair.

  • @mhannan6328
    @mhannan6328 Жыл бұрын

    Terrific instruction. Clear, concise. Your flow is clear. You anticipate questions. Thanks.

  • @nitin8595
    @nitin8595 Жыл бұрын

    Awesome follow up to the last video on wing design. Loved learning about the thought process behind Hollow Grid, in depth. Great stuff!

  • @KiimiKooooo
    @KiimiKooooo Жыл бұрын

    Just amazing, thank you so much! I don't recall ever been that captivated for something that technical before

  • @javiartbarreda3851
    @javiartbarreda3851 Жыл бұрын

    Looking forward for the test flight!

  • @simonbaxter8001
    @simonbaxter8001 Жыл бұрын

    Fantastic video! Being a traditional aluminium construction kinda guy, this was extremely educational. Looking forward to the next one already.

  • @edog7059
    @edog705910 ай бұрын

    Designing and building a plane is pretty cool but the materials and structure knowledge your team has developed is even more impressive. Honestly, with your skills, you could probably be designing and building about anything!

  • @Grarder
    @Grarder Жыл бұрын

    This was incredibly well explained and you're a very good speaker! I'd heard of the DarkAero but wasn't really following it, I watched this out of pure engineering curiosity. Definitely interested in hearing more.

  • @onethousandtwonortheast8848
    @onethousandtwonortheast8848 Жыл бұрын

    I always look forward to your new releases. These videos are great for educating and building confidence in your design. I’ve always wondered however why are you teaching building classes to people who are not necessarily interested in building your aircraft?

  • @Jack-ne8vm

    @Jack-ne8vm

    Жыл бұрын

    Diversified income, fresh ideas brought up by students, future employees...

  • @Michallote

    @Michallote

    Жыл бұрын

    This channel is a Gem for the engineering community, it doesn't has to be applied on building specifically their aircraft in order to be useful for us. Knowledge is always useful

  • @michaelspunich7273

    @michaelspunich7273

    Жыл бұрын

    For the same reason you and I watch their videos

  • @roweboatracing2606
    @roweboatracing2606 Жыл бұрын

    Phenomenal video! I wish I had seen this one year ago before I designed the airfoils structure on our FSAE car. Going to pass this video on to my classmates.

  • @Mrsournotes
    @Mrsournotes Жыл бұрын

    Big Burt Rutan fan here. This generation it’s Dark Aero. Nicely done fellas.👍🏽👍🏽

  • @parrotraiser6541
    @parrotraiser6541 Жыл бұрын

    It's always nice to see machines being built as embedded thought, taking maximum advantage of the properties of the materials. Relates to "Zen and the Art of Motorcycle Maintenance.

  • @JH-tc3yu
    @JH-tc3yu Жыл бұрын

    You guys are absolutely killing it

  • @davidstrong7854
    @davidstrong7854 Жыл бұрын

    not sure why Im watching this , but you sure make it interesting to see all you put into it. can't wait to see the final product.

  • @telakos
    @telakos Жыл бұрын

    Great explanation, I undestood most of it and I'm not an engineer.

  • @plmarshall30
    @plmarshall30 Жыл бұрын

    I would love to know if you guys have been surprised by anything you've learned yet while building this very coot plane? Is there anything that you just didn't even think about or is the building and design process calculated to the last detail and you haven't been surprised by anything? Keep up the cool videos, I get excited when I see a new one.

  • @DarkAeroInc

    @DarkAeroInc

    Жыл бұрын

    Hi Paul! Thanks for checking out our videos and thanks for the great question. Yes, lots of surprising challenges popped up along the way. A big one was canopy manufacturing, which turned out to be much more involved than expected. We spent too much time on that before we ultimately outsourced the process. We might try to bring it back in-house at some point. Making large honeycomb sandwich panels to meet our own standards turned out to be hard as well. We figured out how to do it at a small scale pretty quickly, but scaling it up was difficult.

  • @francisunderwood9998
    @francisunderwood9998 Жыл бұрын

    Love you guys. Because of you I can understand how to make a good design as a erospace engineer student

  • @jlunde35
    @jlunde35 Жыл бұрын

    Love this content. Thank you. I heard about galvanic corrosion problems joining carbon fiber to metal. So many issues. Great job.

  • @Datamining101
    @Datamining101 Жыл бұрын

    This is interesting. Love to know more about the testing and simulation, in particular higher energy dynamics, heating, impact, electricity, etc.

  • @SuperYellowsubmarin
    @SuperYellowsubmarin Жыл бұрын

    That was a treat. Lately, I too am using carbon fiber (foam cored) sandich panels, CNC cut to manufacture the internal structure of an aircraft. I second that the benefits of that approach being no-tool, large stock, easy design change, are extremely undervalued.

  • @theonlyari
    @theonlyari Жыл бұрын

    I really appreciate your hand drawn stuff.

  • @LoanwordEggcorn
    @LoanwordEggcorn Жыл бұрын

    Thanks for a very clear explanation. You're an excellent teacher. Definitely want to hear how you're building this. Subscribed.

  • @mcanderson0
    @mcanderson0 Жыл бұрын

    your presentation is getting better! Much more prone to keep watching; doesnt feel too slow as some have felt

  • @EllipsisAircraft
    @EllipsisAircraftАй бұрын

    Brilliantly concise explanation!

  • @thebogy
    @thebogy Жыл бұрын

    I love the videos. Would love to get some updates on testing. Like what's the progress, is there rough timeline for first flight, etc.

  • @sardcanada2640
    @sardcanada26407 ай бұрын

    Very intelligent engineering related to manufacturing simplicity. That was your biggest achievement. Smooth and deliberate presentation of information. I love the hollow grid design, it is more organic and this should be the direction taken psychologically with all engineering and architectural thought processes. Well done gentleman, I will take your course as it sounds like great FUN ! And it may give me new insight to precast, aerated concrete panels inlaid with an organic matrix. Thankyou.

  • @vmpgsc
    @vmpgsc Жыл бұрын

    Great content, love your clean whiteboard sketches.

  • @jbrownson
    @jbrownson Жыл бұрын

    Loving these videos, thanks for digging into the engineering

  • @royvreeland1609
    @royvreeland1609 Жыл бұрын

    Absolutely love watching your new videos. Can’t wait to see this thing fly. 🎉❤😊

  • @michaelguy7168
    @michaelguy7168 Жыл бұрын

    Great information, really enjoy the technical side of design.

  • @AJ-zj4ml
    @AJ-zj4ml Жыл бұрын

    Absolutely excellent video. Your methods and design techniques are very impressive.

  • @terrancestodolka4829
    @terrancestodolka4829 Жыл бұрын

    Wow, Carbon Composite magic... Nice to see you in the future of aircraft being done this way.

  • @nwbackcountry5327
    @nwbackcountry5327 Жыл бұрын

    I need one. Can't wait to place an order.

  • @SteelDogFab
    @SteelDogFab Жыл бұрын

    Fascinating. Love your guys work

  • @troygiampietro9570
    @troygiampietro9570 Жыл бұрын

    Awesome video, great explanation. How are you bonding the ribs/shear webs back to the skin with the distributed spar?

  • @WPGinfo
    @WPGinfo Жыл бұрын

    Great content, well structured and presented! Excellent!

  • @DarkAeroInc

    @DarkAeroInc

    Жыл бұрын

    “well structured”…I see what you did there ;)

  • @janbergendahl
    @janbergendahl Жыл бұрын

    You guys are amazing! Cant wait to see this fly.. 🙂

  • @brighambaker3381
    @brighambaker3381 Жыл бұрын

    Fantastic video! Thank you for sharing!

  • @Humble_Electronic_Musician
    @Humble_Electronic_Musician Жыл бұрын

    Chances are low that i will build my own airplane (except a small one out of paper) , but i really enjoy your vids. Very informative and a joy to watch. Well done!

  • @Johnny-Too-Bad
    @Johnny-Too-Bad Жыл бұрын

    excellent info and you manage to fit it all on one whiteboard!

  • @felixcat9318
    @felixcat9318 Жыл бұрын

    Outstanding presentation and narration, clear, concise explanations of technical, engineering and fabrication matters. Subscribed.

  • @DarkAeroInc

    @DarkAeroInc

    Жыл бұрын

    Thank you for checking out the video! We appreciate the kind words too. :)

  • @benjaminschaefer6757
    @benjaminschaefer6757 Жыл бұрын

    Brilliant work and excellent video.

  • @johnelliott4521
    @johnelliott4521 Жыл бұрын

    Great approach to strength weight ratio

  • @strugglingengineer1465
    @strugglingengineer1465 Жыл бұрын

    You finally answered my question with this video.

  • @stanislav770
    @stanislav770 Жыл бұрын

    Apprendre comment construire son propre avion est bien . Compliments pour le cours très instructif

  • @asteriskman
    @asteriskman Жыл бұрын

    Never before appreciated the nuance of an I-beam the way you describe.

  • @compspace
    @compspace Жыл бұрын

    Can’t wait for the manufacturering video, great video 👍

  • @PatrikHlebecStor
    @PatrikHlebecStor4 ай бұрын

    Amazing explanation!

  • @Pawe-mx9wc
    @Pawe-mx9wc Жыл бұрын

    Wow this is very interesting, thank you for your educational videos.

  • @jphillips5576
    @jphillips5576 Жыл бұрын

    Another amazing and informative video! 👏👏

  • @michaelstadnikfilm
    @michaelstadnikfilm Жыл бұрын

    Thanks for sharing your work, it's really interesting!

  • @OliverFlying
    @OliverFlying Жыл бұрын

    Awesome video once again guys !! Thank you 🙏

  • @rschaffer8
    @rschaffer8 Жыл бұрын

    Excellent presentation.

  • @noonehere1793
    @noonehere1793 Жыл бұрын

    Excellent presentation !

  • @FlyingInEurope
    @FlyingInEurope Жыл бұрын

    Lovely explanation!

  • @air-headedaviator1805
    @air-headedaviator1805 Жыл бұрын

    This is really sick stuff, innovative, different. Interesting thing I noted about y’alls hollow core concept is that something similar is has been used in some 3D printing RC airplane designs too, going as far as to place stingers at angles to the width span of the wings. Its all fascinating

  • @EllipsisAircraft

    @EllipsisAircraft

    Ай бұрын

    A similar design is used in fighter jet wings also. One that comes to mind, is the F-104. Where compressed bleed air from the engine was sent outboard through the wing, and emerged from ports precisely located to blow air over the flaps when deployed. "Blown flaps" as they were called, reduced approach speeds significantly as long as the engine was kept spooled up and compressing plenty of bleed air. Losing the engine in this configuration, when landing, was unrecoverable. Such were the 1950s.

  • @CraigVanSickleAK
    @CraigVanSickleAK Жыл бұрын

    Great video guys, keep up the good work.

  • @rcnfo1197
    @rcnfo1197 Жыл бұрын

    Thanks for a great overview of your design. How does an all composite structure handle a lightning strike without shattering?

  • @daverobinsonTnT
    @daverobinsonTnT Жыл бұрын

    Love the progress you guys have made over the years I’ve been following your project. Great stuff 👏 Just a couple of questions :- (i) - Have you evaluated fuel flow, migration and fuel bubble criteria for your ‘wet wing’ design ? (ii) - Do you anticipate having to be able to inspect the internal spaces within the wing periodically and if so, does the ‘hollow grid’ construction make provisioning easier or more difficult ? Looking forward to seeing you progress to a successful first flight and beyond 👍 Cheers, dave

  • @scott_aero3915
    @scott_aero3915 Жыл бұрын

    Another great video!

  • @lattermd1457
    @lattermd145710 күн бұрын

    Fun topic. Would also love to see how the fatigue load test is designed and conducted. - formal aeronautical engineer.

  • @juicyriffs805
    @juicyriffs8056 күн бұрын

    Thank you, kind sir!

  • @michaelklepacz
    @michaelklepacz Жыл бұрын

    I love this channel. You’re a bunch of nerds!! Thank you.

  • @DarkAeroInc

    @DarkAeroInc

    Жыл бұрын

    🤓 Happy to hear you are enjoying our channel!

  • @francescomolfetta8053
    @francescomolfetta80535 ай бұрын

    Excellent! I believe in all this.. 👏🏼

  • @wrightjustin08
    @wrightjustin08 Жыл бұрын

    Very interesting design! I thouroughly enjoy watching the process, and the airplane is a work of art! One question though, is there an inspection plan to ensure the integrity of the wing's internal rib structure? For disbonding, delamination, fuel migration into the honeycomb grid structure.

  • @edgararturogomezmeisel2217
    @edgararturogomezmeisel2217 Жыл бұрын

    Nice video. I got interested about your hollow grid concept. Did you analyze the possible failure modes associated to having such a thin sandwich shear webs. I'm particularly worried about debonding in the T joint (between shear web and skin). How did you address this problem.

  • @BuschMarco
    @BuschMarco Жыл бұрын

    Loving the technical explanations. I have a question: if I test a wing like you did, can I fly it later, or would a have to build a new one? Thank you!

  • @P51
    @P51 Жыл бұрын

    really good stuff. thanks

  • @bengeurts6806
    @bengeurts6806 Жыл бұрын

    Interesting concept! Was wondering how did you come to the conclusion about the weight saving of 10lbs? Great content as always well done

  • @johnfitzpatrick2469
    @johnfitzpatrick2469 Жыл бұрын

    G,day Riley, River and Keagan from Sydney Australia. I was wondering how you design structures (aerospace). I knew the components; ribs, spars, struts etc. I now have a idea of testing to resist G force loading. So... one could purchase plans with specified materials or "build and carry out testing to "with a coupon calculations measurement system recognised by the FAA" On the other hand; completely experimental categories. Then there's materials; * Wood, fabric, aluminium, composite material such as fibreglass, carbon fibre in moulds etc. "Speed, just a matter of money, how fast do you want to go?" That was was a great lecture sir, you got my brain to spark on two cylinders. 🍏🇭🇲

  • @tnk.2033
    @tnk.2033 Жыл бұрын

    Keep doing more educational videos ⚡🙏🏻

  • @PeakTorque
    @PeakTorque Жыл бұрын

    Great video, and you are selfless in what you share. Another reason we should be moving away from ribs and spars, is that they are an outdated function. They were needed to take mechanical loads when we had cloth wing skins! Now we have wing skins with serious stiffness/weight properties, we really don't need them so much! Yes theres shear to deal with and face collapse, but i love your design. Be really interested to know how you connect the cell spars to the upper wing skin when you close the structure, how do you know the glue is touching? :) Cheers from UK

  • @nickolayjelev6077
    @nickolayjelev6077 Жыл бұрын

    Nice one guys, what you have achieved so far is brilliant! Keep it up! Quick question: How do you ensure that any ethanol content in the fuel does not attack the sandwich pannel epoxy exposed to fuel in the fuel tank?

  • @willhibbard3137
    @willhibbard3137 Жыл бұрын

    Another stellar presentation... We know engineers by their spelling. Schrenk as opposed to shrink is very clever... German: from Middle High German schrenk 'slanting crossed' (from schrenken 'to put across to lay diagonally') Schrenk happens to be very applicable to observed stresses of webbing the weave directionally of carbon fiber material. Thanks for sharing how exactly you guys arrived to the targets of DarkAero's mission plan with carbon fiber material construction. I'm not recalling the fuel system design at this juncture??? Is this a wet wing?

  • @kris2435
    @kris2435 Жыл бұрын

    Thanks for sharing

  • @paulslevinsky580
    @paulslevinsky580 Жыл бұрын

    Love your work. I would think you have a significant gain in torsional stiffness with your hollow mold wing construction because of the multiple closed box sections it creates. I'd be nervous about using any kind of honeycomb core material in a wet wing. A small crack or pinhole will result in tankering unusable fuel.

  • @asharma9345
    @asharma9345 Жыл бұрын

    Dude you guys are Awesome. I will E mail you shortly.

  • @3SM20Pilot
    @3SM20Pilot Жыл бұрын

    Great video. I even knew some of the words.

  • @billmeldrum2509
    @billmeldrum2509 Жыл бұрын

    Fantastic. Very interesting. 🇨🇦

  • @roberttrussell1010
    @roberttrussell1010 Жыл бұрын

    I really enjoy the videos of your progress. I do understand your reason for your design; however, do you guys think that you might design a slightly slower plane with a lower stall speed in the future? I think it would be awesome if you could use the same format with interchangeable wings to keep your cost down. Just a thought. I'm a new pilot and have no business in a plane with thin wings and a high stall speed. I'm sure a lot of new pilots would agree (or at least should agree) you could hit both sides of the sales. just a thought. I can't wait to see the final product. Good Luck!!

  • @DanFrederiksen
    @DanFrederiksen Жыл бұрын

    You have very satisfying engineering and manufacture discipline. Where you might have opportunities is in simplicity. Have you considered a completely hollow closed shell wing? I believe Elixir does this. Because carbon fiber is stiff, it might hold its shape well enough with little weight penalty if any. And the shear forces transferred diagonally on the shell. And such a design avoids any bonding that could reasonably crack. Any presumably lends itself to fast and reliable manufacture. Cost effective. Similar might be possible for the fuselage although you use a somewhat boxy cross section. but let's say you could do the fuselage as a one piece shell or only one bulkhead for a penalty of only 2kg, it might well be very worth it.

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