Heavy Lift Carbon Fiber Drone

We begin a series of videos describing the design, construction and performance of large multi rotor drones.

[@ThePhillipnielsen]

Listening to you talk is like hearing the essence of all physics classes I've ever had through school, and later. It's just so relaxing not having to question what you say, and just nodd in acceptance every time you make a statement. So true.

[@FishAdvisor]

This is one of my favorite videos thus far. All of the information and thorough explanations captivate me! Reading through the comment section is also a breath of fresh air. It's great to see people inspired with science and engineering.

[@TheDRAGONFLITE]

Having studied some of these concepts in school, I have to say you have an amazing knack for technical communication. Much better than some of my professors. Great video.

[@mboland69]

As a designer and builder of commercial drones I was very impressed, as always, with you presentation. Considering your in depth analysis with everything you do I was a little let down right at the end when you opted for closed DJI flight control system. Are you aware of the Ardupilot project, currently being used by such big names as NASA and Boeing? This is a fully featured open source autopilot source involving software, firmware and hardware. Everything you do you are making open source with your detailed content which enhances us all. I just thought this would place your flight controller, the most critical component in any multi rotor, and the only thing that makes them controllable in the air, as open source as everything else you are doing. For your consideration. Keep up the great content.

Spot on.

[@stefengullicksen314]

Great points!

[@freedomfightereric9064]

OUTSTANDING VIDEO! You have clearly put a lot of analytical thought into this project! Well done, looking forward to the next video. Thank you!

[@Flightstar]

Really like your channel, it's rich in technical nomenclature. Like the way your explanations go beyond just the objects themselves and into the material and technical sciences that make up their design. One day, please do a video on your aircraft construction experience regarding carbon fiber. Sounds fascinating. What do you think of weight reductions schemes such as using aluminum wiring and fasteners, Copper wire and steel bolts are so passe' Hollow shank 7075/ 2024 bolts would be the cats ass for these ships. Every oz carried aloft costs billions of electrons.

[@TechIngredients]

Thanks! The balance we are striving for is useful information without extrapolating from dogma. If the viewer comes away thinking "now I get it, it's not really complicated and I bet I could do something even better if I just tried..." Perfect. Your suggestion about the bolts is excellent. Explain the engineering principal of mechanical modulus, find an elegant way to drill out existing aluminum hardware, test the practical balance of strength vs lightness and that would be the kind of video we would do.

[@weatherphobia]

nomenclature? wtf iz that? he never mentioned it.

[@ruburtoe1]

@@weatherphobia lol, the irony. It's the lexicon used in a domain

[@alannormand9384]

In my growing years there was on TV most Saturdays / Sundays a science show. It was I remember (Mr. Wizard) you pick up where he left off. Getting some of we older folks to think of what is out in the world. Thank you, Alan

[@TechIngredients]

Sure. The motivation is the same.

[@myrandacollins9025]

draganfly is undoubtedly the best drone company! It is providing support in ukraine by supplying ukrainian people with medicines, insulin and much more. with this it is increasing its visibility and brand awareness. has an experienced team and unique technology, currently very underestimated based on its potential!

[@lorriecarrel9962]

Yes the world needs more of you...I genuinely thank you for these great videos you do and hope for much more to come

[@timmylassie6763]

I love your videos - I am a retired aero engineer with lot's of aircraft and drone experience. I wish I had the ability to explain things the way you do. Your explanations of things do require some engineering and mechanical skills on the part of the listener which cannot be avoided without making it TOO simplified. When I watch your presentations I can follow the technical flow of what you are telling me usually on the first pass no matter how complicated the subject. Keep up the great videos....

[@navinsingh1730]

I have a question, how do you make the least amount of supersonic drag?

[@tomaszkoszela8433]

I can't even imagine how you can have so much passion, patience, knowledge and determination to implement such complex projects from A to Z. All your videos are amazing

[@TechIngredients]

Wow, thank you!

[@therealgaragegirls]

I'm in awe at the depth of your knowledge in all these videos.

[@rigilchrist]

You are so good at explaining everything. I do wish you'd been my teacher - or dad!

[@charadremur333]

Ask for adoption?

[@imbabyface]

Very intelligent explanations on the reasons for the choices made. Wow

[@Electronics61]

Great video again. Thanks Great Topic

[@BarefootBeekeeper]

Excellent explanations of some basic engineering concepts. Looking forward to seeing that thing fly!

[@AaronSchwarz42]

"Dihedral looks sexier & I like that too " says the polymath genius :) Earned a favorite video spot on my list! Cheers buddy!

[@guloguloguy]

IMHO: Your FANTASTIC VIDEOS ARE AWESOME, INFORMATIVE, and BETTER THAN ANYONE ELSE'S!!!! WOW!!!!! VERY INTERESTING, and INFORMATIVE!!!! YOU'RE LIVING THE DREAM!!!

[@MarkBTomlinson]

Informed intelligent articulate and entertaining presentation, thank you!

[@anchorbait6662]

Wow. 20mins, I don't think I even blinked once. Fascinating stuff. You are a wealth of information and experience. Who are you? Do you have any other ways I can follow your projects?

[@brucesearl4407]

Ok. I stumbled across your channel somehow... but now I'm hooked. Love your deep knowledge of all the engineering details. It's like you were born with an erector set in your hands and just kept building and creating for the rest of your life! ;-) Great Work!

[@russellcole3549]

You are just about the best science teacher I have ever seen, and I had 24 years of education before I was through, although I ended up with degrees in "political science" (which isn't a science at all) and law. Please tell me that you don't merely make KZbin Videos. You do teach at some college, right? You have a talent that, unfortunately, is far too rare in my profession as a lawyer, which is that you explain complex concepts in plain English without wasting a lot of time or words.

[@TechIngredients]

Thanks! I assume the viewer genuinely wants to understand and is able to understand. All I have to do is link principles to what is already known.

[@antonnym214]

I had to look up what an ESC is (Electronic Speed Control), just in case anyone else had the same question. all good wishes.

[@among-us-99999]

Your Videos really help me to design my own stuff!

[@TechIngredients]

Great!

[@Xfactor7430]

I agree.. this guy for president.. hell world leader for all I care. An overload of skills.. its stunning

[@lorriecarrel9962]

I'm so entertained by his videos,such good education and knowledge explained in a understandable way

[@timcollins3484]

Cant wait for the next video - this is exactly what we need for a delivery system, thanks

[@VoltageGuy2000]

For anyone wondering, ESC= Electronic speed controller, and is required to drive brushless motors.

[@morkovija]

holy moly the knowledge depth! thank you

[@Duncanwg7]

Do you have a website with more of the technical specs and parts?

[@basspig]

That message is angling the rotors slightly off of vertical also prevents a condition during rapid descent known as Vortex ring State. This is a dangerous condition which can cause the aircraft crash.

[@pedzsan]

Request: please add web links to the products that you pick or web sites that you find useful. Some people put this in the description but I gather that that has problems and so other sites put the information in a comment and then "pin" the comment so it stays on top. I just discovered this channel a week or so ago and I'm poking around going through the various topics. Excellent work. I hope you are still making videos.

[@TechIngredients]

Thanks for the suggestion. We're working on several new ones right now.

[@andrewbeaton3302]

YOU'RE A GENIUS!!!

[@TechIngredients]

I keep saying that! My family just rolls their eyes.😕

[@clist9406]

Those are some serious motors

[@alpinerobotics6420]

very nice construction, modular thoughts, very nice design, exactly as I would have wanted it !

[@freeelectron8261]

Another quality video from TI. Thanks!

[@Prop-A]

Thank you for sharing all this knowledge.

[@AaronSchwarz42]

This is a compliment, I think you can make an autoclave // or buy a used one to fix & upgrade it // given that you can design & make controllers & are familiar with vacuum pumps & vacuum bagging / & metal fab / you could probably make a propane heated, nitrogen purged, steel tube with hydraulic door & oilless compressor // DIY orbital welding & DIY NDT camera for testing analysis for safety to make sure its welded without defects so it does not turn into a pipe bomb when operating // You can buy the larger steel ring sections prefab & have then sent on a flatbed/ Premake the foundation & then mount it & finish it, then cover with a shed or steel building /// the heat from the autoclave will warm the building // then you can DIY some dope custom carbon fiber stuff //

[@NikoxD93]

Learned a lot, love the detailed explanations

[@danik321123]

Amazing! Thank you so much for your videos

[@TechIngredients]

Thank you for watching and for your support.

[@AaronSchwarz42]

I am really curious what this guy was doing before he started making educational youtube videos / he sounds like a physics professor crossed with a gifted mechanic & machinist with a spirited teacher talent & gifting & very articulate & intelligent! I would be honored to meet him in first person!

[@charlesklein7232]

LEARNED ALOT! and i have basically given up on trying to build a quad-copter! i was going to use 12 double same motors as your but if that fails with double props its pointless. unless again you can build a bigger motor! but again their is the cost of the prop!

[@patrickdubois7997]

Hi i'm a composites technician and your explaination are very good and very interesting project.

[@totherarf]

Really good video! There are two points that occur to me (and you may have looked at and discounted them) 1. Carbon conducts electricity! Why not use it as a return path for your motors / batteries reducing the wiring needed! 2. The propellers you have seem to be almost uniform in depth of materiel. This would simply have the effect of pushing the air in one direction. If you look at the cross section of any lifting body (plane propeller, wing, windfarm blade etc) you see there is a more complex form where the lift is generated by the paths of air above and below having different lengths causing a partial vacuum being formed at certain speeds! This lift is actually greater than the force of the air being pushed downwards! As I have said they may have already been discounted for good reason!

[@keantoken6433]

Carbon is conductive, but not very much. That means it is very efficient at turning electricity into heat. The energy lost would almost certainly be more than the weight savings of some wire.

[@takeyoshix]

What an awesome explanation. I feel like I can start trying to build one myself now.

[@TheoSmith249]

the best description of dihedral yet!.. thanks

[@TechIngredients]

Thanks. Have you taken a look at some of our other videos?

[@TheoSmith249]

I will be, your edification rate sync's nicely with my receptors.

[@shahabkhodadoust7152]

How nice of you. Thank for great video.

[@moshet842]

Have you looked into the arducopter platform? I think it is a more mature flight system than what DJI has. Especially with the new Pixhawk 4.

[@MichaelGustavsonArchitect]

The arms on this drone look exactly the same length diameter and material as a modern day carbon fiber hockey stick! Using the hockey stick tech, you might be able to get these even lighter.

[@nickfitz9800]

Why are these types of videos not the most popular on You tube. I love watching your videos. I learn a lot. Learning and passing on what we learn has to be one of the most important aspects of human life. Thank you. What did you do for a career?

[@MrRipplefix]

I shared this on Facebook!!!

[@rapfuelpodcast336]

That is a huge drone!

[@quadspeedfpv]

Hello my name is Justin Wilkes better known in the drone community as Swoop I am a freestyle pilot and Ariel videographer as well as Rc aircraft designer and engineer and from the perspective of someone who has been in the RC community for 20 years you are doing some really good work I really like the direction you are taking your research what grows the technology that advances us farther are people that are not afraid to experiment in the unknown keep up the good work.

[@TechIngredients]

Thank you, that means a lot!

[@basspig]

I've used my Phantom 4 Pro to erect a 90 foot vertical antenna. It's my best antenna on 160m.

[@letmelooktv]

keep thinking im watching Cody from the future :D

[@TheHermitHacker]

Bring medical supplies to remote areas where roads are impassable much of the year.

[@photojunkysdronezonevlog]

Great video and you are my idol :-) there is however one thing I disagree with in your design. I would not charge the batteries on board. About a year ago, I had a battery fire for no apparent reason. There was no damage to the area around the battery since I had it in a fireproof bag, but with your design if you were to have a fire, it would take out part of your creation. Other than that I love everything about your drone. You just got another subscriber.

[@denniskatinas]

On drone charging is the future. Roll with it.

[@freejulianassange3143]

Yeah, drop and roll.

[@skuzlebut82]

You have motherboard boxes, looks like external hard drive boxes but you've got a couple of spools of carbon fiber. All things I love. "-)

[@TechIngredients]

My son builds the computers, I just glue things together.

[@skuzlebut82]

Tech Ingredients Could you email me at shawnpwest at gmail dot com please? I tried contacting you via Facebook but it doesn't look like you use it much.

[@adriansalustri5558]

I love everything about this guy.

[@TechIngredients]

Thanks!

[@PrestonK92]

This guy is a legend!!

[@AaronSchwarz42]

Good point about the directional strength of carbon fiber when you lay it up in the direction where the strength needed. BMW did this in their hot glue fast hot cold press manufacturing of the i3 body shell // for low cost vs autoclave baking aerospace // lots of that PAN cooked in Washington State over in Grant county where electricity only $0.023 per kWh // cheapest in the world // from abundant hydropower DAM output //

[@richardgshields]

I just learned a shitload! Nice job man!

[@TechIngredients]

Thanks!

[@RevAldea]

An English aircraft maker has found that when placing two propellers close to each other that these pair must rotate oppositly this then adds to the propellers total out to a greater amount than two single rotating propellers side by side. this is because the first prop slide the air along with it somewhat and when the second prop hits the sliding airflow effectively increases the attack of the second propeller then has greater output of thrust, making the total greater than the whole added singerly.

[@TechIngredients]

I didn't find this to be the case. Counter rotation was superior to simply adding blades to an existing propeller, but I have not seen that claimed increase in effeciency. It may also be dependent on the radial velocity of the blades or the forward velocity of the aircraft. All my tests were static and done at moderate RPMs as well.

[@MadScientist267]

Man you're who I imagine my dad would have been had he made it to see all this and had all the toys to play with at his disposal... Maybe something to that lol.. I found you on recommendation for the speakers, my dad was heavy into audio, I just restored an Akai R2R for my rig, blame him for that as well... Anyway, haha all this nostalgia aside... To say, you're great man. Every one of these videos is not only comprehensive and in depth but other than minor errors (verbal typos lol) and the occasional glitch we all make... Has been spot on. Hands down this is one of the best resources on KZbin for a curious electrophysichemichanical (new term, just made that up right here lol) DIYer there is. Thanks for all the great info and reminders of a great man in my life. Much appreciated.

[@35oz19g]

So you just restored an akai R2R, but you cant put your own thoughts into words? I call BS! Your daddy must be proud of his little soilder in the YT comments flatulating hot air AND typing on a keyboard at the same time! I think i see him looking down on us right now....wow....wait....i think thats just santa clause. My bad buddy. ✌

[@ronroberts110]

In the oversized bolt discussion at 11:00, you might consider on future projects to bond an aluminum cylinder through the hollow spar for the bolt to ride in. I think this would be stronger enough that you could use a smaller bolt to achieve the same weight as before, but much stronger than the current arrangement. Excellent videos, good details as to the choices made. I learn something new every time...

[@TechIngredients]

Thanks! You're suggestion might be a little lighter, but it probably won't be stronger. The spar can't accommodate a larger diameter aluminum tube, bolt etc.

[@arloc_official]

i learned more from this video than from a whole school year

[@SevenDeMagnus]

The pre-made carbon fiber brands are Rock West and DragonPlate.

[@lionlinux]

He does love this things obviosly!

[@renzotoglia]

thank you

[@BenJaminLongTime]

I really like how technical you get, I imagine you are probably an engineer by profession just based on your detail and nerdy-ness lol (sure you might not be, but if you arent you should be). Much appreciate it as an engineering student myself who likes to know specifics of design.

[@TechIngredients]

Thanks!

[@BrendaEM]

Excellent design and build. Making the top and bottom plates of unequal thickness was a good call. It's a great drone! You might be able to save a little weight for free by using larger radii for the tube brackets, but you may have to be a but more careful with it while it is folded. Seeing that you have carbon sheet goods, perhaps you could make some carbon washers for many of the places, where galling might not be an issue. Stover (ovalized) might be lighter than the Nylock nuts, though would only be appropriate for the fasteners which remain fastened. Bicyclists and motorcyclists have made titanium fasteners more common, but they lack in toughness compared to steel. [If you ever do make another you might use Grade 8/ Class 12.9 fasteners of smaller diameter.] Because the props are close to the tube it might be a bit more efficient to use a symmetrical airfoil near the motor, with the trailing edge facing down. If the props were higher from the tubes it would lessen the difference, but spacers would cost weight. If the motor drivers get hot, could they be moved under the props? Good videos. Thanks.

[@TechIngredients]

Boy, you have a lot of interesting ideas. Some we have considered, but many we have not. Larger radii? Do you mean larger outboard positioning of the aluminum folding brackets, larger spacing of the pivot screws or larger tube diameters. There are trade offs for each of these decisions, but maybe you meant something else. For the larger and many of the smaller Nylocks we have converted to aluminum. This was an EASY improvement...many are not. Strength is rarely an issue with fasteners for these craft, but point loading is. Load distribution with the lightest fasteners that are practical is often preferable. Titanium is not likely to be an advantage unless we wanted to sell this project and we needed to make the brochure sexier. The large rotors we built in subsequent videos were much easier to construct with a flat lower surface. A different construction method might allow this degree of freedom. Why would airfoil symmetry vs say AOA be useful near the motors?

[@BrendaEM]

Well, sometimes the obvious eludes the genius? I should think that the point of diminishing returns is not far off from your design, but are a few grams here and there that might be saved, which add up, and add up to a few more seconds of flight--or a slower decent on a hard landing. I meant a larger radius on the metal bracket, which holds long carbon spars/struts (which hold the motors.) Sometimes, when I draw up things, I ask myself: what has the right and justification to be here. I haven’t seen aluminum Nylocks. Interesting, thanks. Yes, I should think that point-loading / stress concentration is difficult because-not only because carbon fiber a little brittle, but it is so stiff elsewhere which yields little. I’ve worked with fiberglass a fair bit, but that’s much more forgiving. I thought that the spars/struts could be given a symmetrical airfoil shape to let the air pass around, to minimize the stagnation around the sides of the tube. Merging in with your box attachment idea, I drew up this quickie Rhino3D drawing. I’ve tried to keep the faired airfoil shape constant to the edge of the prop. www.dropbox.com/s/advi8vwf804woqw/Quad%20End.jpg?dl=0 Cheers P.S. Some free stuff: openfoam.org www.salome-platform.org/ code-aster-windows.com/ www.code-saturne.org/cms/ www.paraview.org/

[@TechIngredients]

Remember the old adage, "A good tool is one you can't add anything to and a great tool is one you can't take anything from". I appreciate your approach. You might find it interesting to take a look at the history of the development of the early Lotus automotive racing team. They carried this philosophy literally to destruction! Nice CAD. Now, I understand your comment about the arms, interesting, but remember the greatest impact will be where the rotor-wash velocity is greatest. Also, keep in mind that the arms have to resist torsional forces to prevent the discs from oscillating when maneuvering. They will need an increased cord length to compensate for the narrower profile. Still don't understand about the brackets. They are more massive than the arms and the central plate is heavier than both.

[@jaysonlee8625]

I believe that your reasoning for having the Dihedral is similar to the pendulum rocket fallacy. I used to think that way with plane wings too, however the force vector doesn't affect the roll of a plane. it's the difference in forces between the 2 wings that causes the correcting roll and this force is created because of the effect of dihedral on the angle of attack of the wing. Ps, sorry 3 years late

[@TechIngredients]

I disagree. Unlike a wing where the angle of atack is affected by the roll, the rotor's lift is not. Only the vector of its force changes.

[@blueshygaming5190]

@@TechIngredients Jayson is right, in stable air adding tilt to the arms does absolutely nothing for stability. There is no pendulum effect by tilting the arms, weight does not "hang" anywhere on the body of the quadcopter, gravity only acts through the center of mass. If you draw a free body diagram and the accompanying forces you will see this .

[@alisioardiona727]

@@TechIngredients13:25 In your explanation in the video you talk about the vertical component of the thrust vector, but you forget to mention the horizontal component. The rotor that is higher has a bigger horizontal component than the lower one, which exactly compensate the vertical vector component you talked about in the video. I'm afraid my favorit material physics professor fell for the pendulum fallacy.

[@gravelydon7072]

One thing, while this may be a 1.0 version ( or even a 0.7 to 0.9 ) in version 2.0 I would expect to see the wires to the motors moved either inside the tubes or to the bottom of the tubes. Reason being is that it would get them out of the rotor wash. I would also expect to see some sort of change to tubes that were only square at the ends with a triangular section in the middle. While it might take a slightly thicker material, the weight would stay about the same by the drag over the tubes from the prop wash would be decreased. In fact, a tear drop shape might be even better with the round part down. You mentioned the use of an autoclave in the making of the carbon fiber material. In the use of it, it really should be done with a vacuum on it first and then the pressure.The use of a vacuum would draw out any trapped air and then the use of pressure would force the materials together.

[@TechIngredients]

We did advance this design and ran the wires within the tubes. Only rectangular and circular tubes are available at a reasonable cost. You are correct, neither shape is aerodynamiclly optimal.

[@gravelydon7072]

@@TechIngredients With your making of the blades, it shouldn't be too hard to get the foam company to make you the foam shapes that would work the best. I have been enjoying your series.

[@arkiefyler]

Glad I've finally found your vids! Not all that familiar with multi-rotor copters but it took me several minutes to figure out what you are calling "rotors" were actually what I call propellers. In my ignorance, a "multi-rotor" drone is simply one that has 2 or more arms, each with some kind of thrust device. That "device" currently seems to be a propeller with one or more "blades". I will have to be careful in reading about "multiple rotors" having nothing do with the number of blades on the props! ;+) Perhaps this is the standard terminology for these kinds of 'flying devices. Look forward to seeing more of your exercises/experiments!

[@adriaan7627]

Nice to have these followups :-)

[@latergator3367]

Drone On ! I am ready to take flight !

[@Bobbylegs37]

Additionally, a foam or plastic fairing could be added to the arms to reduce drag and weigh almost nothing.

[@TechIngredients]

True.

[@calmatosport]

Your reasoning for dihedral is not really right. Thrust doesn't care about the direction of gravity, neither does lift when talking about a wing. Airplane roll stability works on sideslip angle together with dihedral and crossflow from the fuselage. I like your design tough, high level of engineering detail!

[@per.kallberg]

Ron S The unequal trust vectors in combination with an offset center of gravity gives a torque that ads stability. I found the message rather clear but might of course have miss understood.?

[@calmatosport]

Excuse me for the confusion, I'll try to explain clearly. You can make multiple drawings of the forces acting on a multirotor in different orientations. Here two factors are important: 1) Lift on a wing works perpendicular to the surface, thus thrust from a propeller works in line with the motor shaft. 2) All the masses can be simplified to one centre of gravity (when using dihedral the CG will be below the motors!) When you add the motor thrust and draw the resultant force, you will see that it is in line with the CG: thus no torque is created. Tough there is an asymmetry in thrust when a multirotor with dihedral moves sideways. The relative wind creates a difference in angle of attack on the propellers resulting in a correcting torque and an opposite sideways thrust component. Note that this is a delayed stability effect because it only works when the mutirotor is already moving sideways, it can even cause dampend occilations. Dihedral makes for a less direct and 'true' response and is less efficient in hover and forward flight. No reason to use it for stability reasons when our modern flight controllers have functions such as GPS hold. So dihedral works, but in a different way than explaned.

[@dmendia]

But in this case what makes the drone fly is lift and not thrust, correct?

[@quentincampbell5865]

A bit late to the party (I only discovered this excellent channel today). true that dihedral wings have a total different affect due to airflow. Where as on having rotors on the end has a different affect. But something to consider is that multi rotors got gyroscopes build in, so it will automatically change the speed in the motors anyway to stabilize the craft. I would think even before any diherdral affect comes in to play.

[@frqgrenade]

I wanted to write exactly the same thing. Might add it's just a pendulum rocket fallacy all over again.

[@atomipi]

Quick hint, the square booms add significant resistance to the prop airflow. We made an aerodynamic boom under the prop, and found 65 percent increase in lift. The flat sides didnt make any difference in side wind resistance. In fact the prop thrust over ruled the wind speed, or craft speed at 70k, so there was no side wind seen to impact performance on the side of the boom arm - we also did testing in a wind tunnel, with fog to show wind was massively thrust downwards under the prop.

[@TechIngredients]

A 65 % increase in lift by changing only the aerodynamics of the boom is difficult to understand. This would suggest that if a bench test of your propeller was done without any boom at all, the increase would be at least 65%. Alternatively, if that same bench test was performed and an obstruction was inserted with the same dimensions and spacing of your original boom, the force against that obstruction would equal 65% of the propeller's thrust. I am skeptical.

[@deividasabrutis7248]

So add 15inch long triangles made out of styrofoam they weight nothing but booms will be aerodynamic. But 65% is BS

[@RupertBruce]

I like the Modest Mouse😎

[@DragonTheta]

Great information!

[@williamhinelsey9742]

If you look at gain distribution tubes used at grain elevators (farms), you will see wires (under tension) on four sides of the tubes keeping them straight. This may be a good way to further reduce the weight of the rotor arms and still keep the rigidity needed for the rotors.

[@TechIngredients]

Typically those elevators are constructed from concrete segments and concrete has good compressive strength, but very poor tensile strength. This is the principle that underlies pre stressed concrete engineering. Carbon fiber has balanced compressive and tensile strength and the value of additional stringers would be low.

[@williamhinelsey9742]

​@@TechIngredients I was referring to the grain tubes that feed the grain from the leg, to the top of the silos. Without the tension wires, they would fold under their own weight.

[@madbikerwolf8664]

Wow, almost like a remote controlled helicopter.

[@peetre]

I love your videos, I would like to see you stick to using a lapel mic. I know there is a bit more effort in syncing and editing, but the professionalism is far better. Thanks

[@TechIngredients]

We are now. This video is several years old.

[@SurvivalHunterNM]

Good video. I'm wondering if there would be an advantage to horizontally offsetting the rotors or simply adding four more rotors in an inner circle on the same struts. If you could control 12 rotors at once, it seems like you could fit the additional four on the same horizontal plane, just closer to the center.

[@TechIngredients]

Maybe, but the additional lift would be significantly less due to the diameter of the inner rotors.

[@LuideMulumba]

Did you ever come around to doing the setup video for this drone? I'm really curious to see the build progress.

[@pauld1241]

Awesome thanks

[@onehumanwasted4228]

Main parts: 9225-160KV Turnigy Multistar Brushless Multi-Rotor Motor Dynam 30x5.5 Carbon Fiber Propellers for Multirotors (I guess) Hobbywing Platinum Pro 50A V3 ESC Carbon Fibre Square Tube 20 x 20mm (I guess) 4S Batteries

[@VoltageGuy2000]

Great drone!

[@wizzardrincewind9458]

You can have a propeller with "1" blade and you can make the square tube aerodynamic better with very light foam-material.

[@MrSurok]

very good! good luck !

[@anthaltie]

they could be used for spraying if combined infrared to see the problem spots in the crops and stop problems before they start you could even control pollination which if timed perfectly you could increase per acre production. the next big thing is the collection and sale of pollen.

[@robertonegrin9001]

Thanks

[@twbrkfd1733]

Just found this old video. Very nice! See mine from 2013 at Rockford Quadcopter; SQUARE tubing! What happened to the detail on construction? You go from this video to a flying machine and that's it! How about doing an upgrade; rather that the A2 canned controller; use state-of-the-art parts like the iFlight F7 TwinG (has dual ICM gyro chips) and Advanced Power Devices ESC and PDB. What is the size of the square CF tube? You mention the throttle headroom; an important point is your low-speed application where you don't need high airspeed; high KV motors and voltage, but sustainable voltage. Additionally, why go to the expense of a non-homogeneous square tubing when you could have just added plates to the top and sides at the high stress areas. Are the motor bolts supported by solid material through the tubes to prevent crushing/ripping on impact? Finally, it's inevitable that this will crash and be smashed to bits in a catastrophic failure; be realistic and true to reality and try a drop test from 20 feet onto concrete. Ouch!. Much shorter arms would be more crash worthy. Thanks for informative video!

[@TechIngredients]

Our more recent videos are filmed from this platform. Why crash test this intentionally when as you say it's inevitable? The tube's length is mandated by the rotor diameter which is in turn large to improve lifting effeciency. There are anti crush bushings in the bracket/arm interface. The tubes are about as thin as they get from commercially available stock. They are plenty strong for flight, but in a crash (we have had more than a few, but from less than 20 feet) even a much thicker arm will crack because CF is very brittle and their fragility saved the brackets from damage. We did discover that the large rotors and small, light weight motors were problematic re quick response and maneuvering and at the cost of some effeciency loss they were reduced to 24".

[@caroljeansmith9105]

very educational... Thanks

[@Hellsong89]

Heres a idea: How about adding second set of motors and bladed middle of the arms doubling the carrying capacity? Control system should not be issue, just reduce control values with certain % and slave one controller to another if there is no space for extra motors. This does create wingtip vortexes, but should not adding foldable ring around the blade (essentially making it ducted fan) remove some of this? Or just increase arm length bit more, so each blades vortex wont cause issues. I'm amateur when it comes to RC or anything flying, but with my limited knowledge i believe this should work.

[@TechIngredients]

The second set of motors will have limited clearance and therefore the propellers will have to be smaller and therefore much less efficient. Another option would be to use interspersed large and very large propellers on the end of each arm. If you can visualize what I'm describing, this arrangement allows for larger props on the same frame size, increasing efficiency. The use of ducts is a trade off. They increase efficiency, but they add weight. Generally, they aren't worth it.

[@Guds777]

Big legs like this can store a lot of batteries. Or better cram a small RC nitro engine in there with a 12v generator. ( i did see your drone generator video :D )

[@p39483]

The discussion on dihedral needs elaboration. I see many large drones have it but I don't understand why. The drone is already actively stabilized and dihedral would make a drone respond adversely in gusts while GPS station-keeping. Wouldn't it be better to have slight negative static stability so that the drone would immediately sideslip into crosswind gusts rather than with them, thus staying on station?

[@TechIngredients]

Active stabilization is not instantaneous and has control limits. Establishing a basic passive stability reduces the demands on the active system.

[@caioqwerty1]

Holy crap, this channel is neat.

[@alpinerobotics6420]

If I would have the money I would instantly hire you !

[@mccc4559]

Alpine Robotics, nice comment...what would you hire him to do and what is the rate you would want to pay (if you had maximum funds)?

[@alpinerobotics6420]

140 000 CHF a year,, developing heavy lifting drones as well as R&D

[@mccc4559]

Alpine Robotics, why don't you send him a message and see about working together on projects that could be mutually beneficial? You may have just as much to offer as he does. Sometimes matches are made via random paths that are actually neatly laid out using chaotic algorithms. See how much sense that sentence made? My point is, give it a chance..... sky is the limit. Thanks for replying and best wishes to all.