This is for sure one of the biggest reasons I have so much fun with, and love the fpv & other open-source communities! When we are able to all put our heads together, innovation comes faster, and everyone is able to learn and benefit. (thank you to MIT for showing us this design!)
@@STRIKINGFPV thanks for the explanations. Please look at the three blade vs four blade turbo prop difference in C-130 aircraft. I am confident you are aware what to expect, but it blew me away as a mechanic who flew on both. Cheers. You earned my sub.
Glad you like them! V3 and V2 are out already if you haven't seen, along with a new video explaining more of the concept with questions and suggestions from the community.
If you checked earlier than before I uploaded, there's a 40mm version of my design which might work for you. It's not perfect, it was scaled around from the 2.5 inch version I remade, but it might be viable? Let me know!
FYI: Latest video featuring frequent questions and suggestions is up: czcams.com/video/pjZaGHKQB8Y/video.html Hey all, so I've finished updating the tri-blade tri-loop toroidal designs so it ranges from as small as 40mm all the way up to 6" and I'm going to have to stop there for the next few weeks. Looking forward to seeing tests and hopefully more designs will pop up from other creators and designers soon. Just check the same Thingiverse link. No time to add more bi-blade sizes, but I hope that's not an issue. Maybe you guys can play with scaling it up and down, or someone can remix them with different hubs, etc. I'll still be commenting and replying, just won't be designing when on the road. Thanks again for the likes, encouraging comments and subs, and see you all again in maybe a couple weeks. EDIT: Ooh, ooh, apparently the newer design is lighter, produces more thrust and draws fewer amps than the last time! Check out the short video from Vlade at @QEDFPV: czcams.com/users/shortsTVZxl3116OM Bi-blades/Bi-loop 5" got airborne courtesy of Vladimir over at @maxbl4 : czcams.com/video/wAXWpmX8gcM/video.html Also, Johnny on @willitmod has some fantastic flight footage using the new design printed in Silk PLA which has fantastic material properties: czcams.com/video/UNL8KXdAggc/video.html
@@davincifpv3842 The project file or step file is a huge mess right now, compared to stuff I've done in the past - in the same way that I'd love to do a proper tutorial, I'd love to eventually release a step file when I've got a better, more consistent methodology that won't drive people up the wall wondering why the loft doesn't work or the why the cut command is glitching 😬.
I tested your first design on my 3.5 inch custom cinewhoop and it flew pretty good for the FDM standards of a printer, looking forward to testing these! Will surely do another video, thanks for taking the time to design these!
It’s great to see a project I helped work on from 2016-2019 finally go public. It honestly not a new thing, but we were a lot more comfortable going public after our patent went through in 2019. Also to clarify about MIT designing it, not everyone that’s worked on it is from MIT, it’s only because I worked on the project using their campus and their equipment, we had no choice to credit them for it, but in reality it’s a pretty big collaboration with lots of individuals from different universities.
I hope you don't mind but I've included your comment in my latest video just so that more of the community realise that even on the "MIT" side of things it was a tremendous group effort, kinda' like what we're trying to do now. @RoboticsJoe also mentioned his involvement and I asked if there was anything you guys were willing to share, I'm guessing that's more of a no, understandably, but would be cool to get more insight into what went into the project. Congratulations and thank you for the efforts you put into this concept already!
regarding the velocity-dependent lift: in the low-speed regime (as in "very sub-sonic") the airflow over a prop blade traveling forward increases with additional speed, which, being an airfoil, generates more lift.
My wife and I are blown away by your absolutely perfect English and tone of your voice . It's better than Elglang , American and Australian English. What are you language influences. I'd send every kid in America to learn how to speak perfectly from you .
Haha, funnily I have English, American and Australian influences going on. I'm half Australian, but my dad spent a lot of time in the UK so he sounded mostly English, but television and schools I went to were predominantly American/International sounding so my default neutral accent is mostly American with a few English pronunciations here and there.
Really cool work. I personally feel the two blade/complex props will be a more viable option. Another possibility is to avoid trying to get the blade tip to curve to vertical and then blend into the other blade behind it and instead just make a forward swept blade that's standalone then put a back swept blade in front of it and have their blade tips close enough to connect with a short connector. Not exactly toroidal, just the front blade supporting the wing tip of the forward swept blade tip behind it.
This was suggested by someone else I think in my last video as well, basically having the blade tip being horizontal instead of vertical, but I believe the whole point of the toroidal design is to effectively not have a blade tip, since wing/blade tips are where the most turbulence is created, which contributes to the noise created. A horizontal tip would end up being more like a regular tip, compared to the vertical. I'd like to try the idea regardless, might just make a strange prop with no other real benefits, but first I think I might try reducing the height of the vertical at the end, which might mitigate the issue of the blade getting steeper further towards the edge.
@@STRIKINGFPV you should think about minimizing the weight at the outer diameter as much as possible in future designs. This was the one big disadvantage I found in my testing. Too much weight at the outer rim hogged amps and made them very imbalanced. Otherwise I liked everything about them. Quiet, noticeably thrusty and much more safe.
@@dutchfpv7010 Yes, that's definitely what I've got going on in my head, I'm thinking of reducing the height of the vertical edge, which should hopefully also result in shallower blade angle closer to the edge. In theory that will also reduce the weight near the edge, and give these props better response. In theory 😅
Air plane designers have had lots of iterations designing blended wingtips which didn't really adversely affect cruise drag, reducing tip vortices when slow and heavy - around airports is one thing (safety), getting lower drag numbers for cruise is important... This is probably where this design is at right now, fighting the design optimisation between blended wingtips and scimitars.
I pride myself on eloquent speech when in the moment 🤣 For those wondering, blade tip airspeed is higher because it's travelling/sweeping across a longer distance in a single rotation compared to say the base of the blade at the hub. Hooray reasons and how rotation works!
I had some ideas for improvements you implemented. love to see that! I posted some of them and some accured to me later, but it looks like you had the same ideas :D I think the improvements you did are really a good step forward! I am really looking forward to how the design will improve over the next generations and might become better than traditional props in many ways.
Crossed fingers that we get there, but much like various developments in FPV's past, never know if something eventually falls by the wayside. I hope these props go the distance, but there's a good chance that they won't either. Gotta enjoy the journey though, haha.
CZcams suggested this video for me to watch. Most likely because this same subject was in a video on Major Hardware's YT channel. After MIT came out with their findings, Major Hardware guy printed one of these to try it for a PC cooling fan. So I speculate that some of your 400 new subs are like me and also sub to Major Hardware and our interests are piqued lol. I enjoyed your video today and look forward to more of your creations. Have a great day.
😅 same alghorithm victim here. I saw the video of the pc cooling fan and yesterday I get the suggest of yt for this channel and now I want to repair my 3D printer for an experiment…
All hail the algorithm I guess, haha. Cheers for stopping by and glad you dig it! Won't be posting for a bit so feel free to explore the back catalogue 😅
Found you via Will it Mod, this sort of design has grabbed lots of attention. In the late 1980's I was using 12" multiblade props with a ring on the tips. Crashed many times, props survived, everything else broke. Mechanical gyros suck.
Oh crazy, so they were like those plastic toys but actually on an RC plane? 12" is quite large for a prop, but I suppose back then materials were heavier so larger scale was the thing. I remember as a kid my dad had an RC glider which had a brushed motor with gearbox (folding prop blades for when the motor was turned off), a chunky NiCad battery and the whole thing was balsa frame covered with thin (maybe 1-2mm) plastic. Very heavy actually, but at its scale light enough to fly. Wouldn't want to get hit by it, not like these EPS foam PNP kits coming out of China these days. Now that I think of it, maybe that glider we had actually had a 12" prop 😅.
Ps, thanks for new design! I'm also excited to try this and the whole collaboration thing! :) You spelled my name great, i know how hard it is for non Slavic people
I have a few Eastern European friends here and there, and I enjoy getting pronunciations right if possible 🙃
Před rokem+1
i think everyone needs to consider the old school round circle around a 4 blade prop its an old design that every quad used in the beginning it works its quiet and doesn't cut you when it bumps into a hand or face.
I remember having toy plastic helicopters like that, hours of fun, haha. Not sure how those would stack up, though, because a big part of high performance FPV drones now is prop response, and having a ring all the way around the outside would result in a lot of added and aerodynamically useless mass which would lower prop response. I think the toroidal prop could possibly end-up being like a middle-ground between open props and the old ring ones that you mention. This being said, it would be worth doing a comparison between all three, definitely.
A couple of additions from fluid dynaics in submarine propeller blade designing: On the forward spinning half loop (meaning the "quick vertical" leading (top edge) add "Barnacles" meaning bulb-like bumps in an eroded cone (barnacle) shape along the top edge. Add the same to the rea-half-loop's trailing edge, facing down. Additionally, add micro dimples to the surfaces of the loop, like a golfball. What will result is a better pattern of the prop's eddy wash. You could add internal piping from a leading-to-trailing barnacle. but what you really want to evaluate is the eddy wash.
Just an update from my short testing. First of all was able to successfully print these props with PLA, PETG and Nylon. My testing was with a 3" Tyro 89 which is a cheap ass quad I know but it flies well, at least for me, using a default BF tune. Testing results were the same for both PLA and PETG. In both tests I was able to achieve flight and both sets of props held together just fine with no apparent deformations, stretching, etc of the props. Hover flight exhibited wobbling/stability issues that were controllable sort of. This was also true for small slow changes in direction. However normal paced flight was pretty much uncontrollable. Motors and battery were very warm to the touch at the end of the flight. When using normal props on this quad the motors and the battery are dead cold at the end of the flights. Flights were conducted in angle mode which as I am writing this I am thinking that could have exacerbated the situation as the quad was perhaps trying to self level itself instead of depending on my inputs, don't know for sure. Perhaps someone could chime in if they had seen a difference in stability between acro and angle flight modes. Finally didn't test with the nylon props due the poor results from the first two sets (PLA and PETG).
Like one of our earlier testers, they had crazy wobbliness from angle mode, but acro hovered fine - also, many people have noted that PID tuning is most likely required, with some testers lowering their D term to good effect. This being said, have you tried the V3 props yet? @WillItMod tested those and liked how they flew, they seemed the most normal-behaving design compared to the earlier two generations.
We've been doing a lot of quiet prop designs ourselves and a lot of people have sent us your video. Absolutely enjoyed both videos! Looking foward to see your own test results after you get access to your 3D printer
I don't even have a drone but for some reason I got the MIT stuff recommended and now I'm down this rabbit hole of people experimenting with toroidal propellers on drones, it's really cool to see though how the community is in this experimental phase right now, just trying out all sorts of versions of the MIT design
Just subbed because of the prop and possible use in water pumping efficiency. Three decades ago I told my students young folks had to sort out the problems of the future. Well, I was right about that. Thanks!
I loved to see such experimenting. With FDM printers have you considered Polypropylene? It also has glass-fieber composite types. Its an interesting material, more flexible than TPU, less fragile than a harder neon. Layer adhesion is exceptional. Sticking it to bed can be tricky, some manufacturers' product warp a lot, but I'm satisfied with the one I bouth from Amazone, called Braskem. What I saw from tests that these are heavy and need quite some torque to react for quick stability maneuvers, so maybe larger diameter motors with lower stator would be more beneficial.
My harebrained concept. I'd mod the two toroid design. View top down, rotation counter clockwise. Draw a line from tip to tip through the center of the hub. Cut the toroid tips. Leave the trailing half, and remove the leading half of the blade. Then duplicate the trailing halves into a 6 blade prop, with the blade looking like a forward facing scoop. Make the prop from light rigid material like carbon fiber for minimum deformation at high rpm. All performance testing should be done on bench mounted stands to compare thrust.
more lift at speed = ETL. Effective Translational Lift. A key aerodynamic of helicopters that I've always wondered the reason why wasn't really a noticeable effect on mini quadcopters. The effect is because the drone is sitting in its own vortices until it gets enough horizontal speed that each rotation of the prop is finding "clean air". I suspect it's due to the thrust to weight ratio of the drone on these props is quite low. He does appear to be flying very slowly compared to what I'd expect from a drone of this size. This suggests the props he's using are not very powerful at all. Props to you (lol) for designing them but I doubt they are anything close to aerodynamically ideal, and of course the 3D print is going to be heavy and rough compared to any injection-moulded nylon. We're just getting started on this journey. I'm really glad you knocked out a testable design so quickly, and can't wait to see where this goes.
I did a roll on same day, check my next video :) the first vid had wrong pids. I was worried about bad balancing of props, and added too much filtering. But after checking bb, found there are no noize problems, cranked up the pids and got it flying pretty stable
I think we're all just very concerned because of how patents are often used unfairly, more-so in the software space admittedly, but it's something to be cautious of. That being said, I don't honestly think MIT would try to stop us from messing around with the concept, I think they'd only step in if a large commercial entity started spitting these out with licensing, so like DJI and other larger scale manufacturers. I do touch on this a little more in my latest video.
Awesome work! We really needed someone who would carry out precise research to improve the efficiency of the blades in the world of small aircraft. The idea on the TPU is interesting, but it makes me doubt, at high rotation speeds as well as sudden accelerations, the elasticity of the TPU could generate instability or latency, in the control of the aircraft .... I would opt for the use of much more resistant materials, at a mechanical level. Of course I'm sure I know a lot less than you about it! So I just hope you can continue with this project!
You're right, some people have already mentioned that the TPU warps too much at high speeds and acceleration so it's a no-go. I've addressed this in my latest video as well, everyone should ignore my past suggestion 😅
@@STRIKINGFPV I'm glad you're continuing the experiment! I'm off to catch up on your latest video right now. I can't help mentioning a few things I've noticed while examining some other users' tests: it seems that this toroidal design is very inefficient at low rpm, both in terms of thrust generated and in terms of noise, while it improves when it reaches high rotation levels. Of course it is a bit unbalanced to compare them directly to industrially produced propellers, which also have a smoother surface. Most likely by printing them with a 4K resin printer, using a good resin, you could have some improvements in aerodynamics...
@@lucamagni99 Oh totally, honestly resin is the only way to go to get comparable results to production props, but I love keeping FDM in mind because FDM, to me, is more the spirit of the maker and the creator, it's still the most accessible printing method for home tinkerers and so being able to produce these props on FDM and have them fly pretty-well (a la @WillItMod's tests) is very exciting, actually. Let's say we'll leave resin for the serious scientists, but we're not leaving our FDM people behind either 😁
@@STRIKINGFPV I completely agree! From an economic point of view, maintenance, and above all safety in terms of health, fdm printing is undoubtedly much ahead of the resin one. Not to mention that the main reason why I prefer it are the printing times, and you can check immediately if the printing started well! Perhaps it would be interesting to experiment with a print, using a 0.1 mm nozzle, and a carbon fiber enriched PETG filament, to keep the weight down...
Ok yeah I got it. In acro mode it can change input faster so it can correct itself faster, thus better stability. That's a little odd but not entirely unexpected. I think it's all pretty fascinating and I do like the fact that they emit less high frequency noise, but to be a game changer they really need to yield longer flight times than standard bladed props. And yep, I agree. Tri-Loop®rolls off the tongue way better than tri-toroid. 🤣 Very nice work on all this, bro. Very cool. Keep it up!
Well, it's weird because in acro, you're only using the PID loop to change the drone's orientation, but it's not actually referencing any absolute rotational positioning in the world. Angle mode, however, is using the accelerometer part of the IMU to determine where "down" actually is, and such if the PID tune isn't tight enough then the angle controller needs to give extra command to correct the situation, but with the bad PID tune it seems to overshoot and flip flop. So yeah, PID tuning in acro mode is very important before hoping for reliable angle mode performance.
Interesting - While I have no access to actual drone hardware - I used this to practice a bit of Fusion 360. My design last night also used 5 profiles - two at the root, two at the leading and trailing pieces, and the last at the tip. What I did though was make the tip still angled. This seemed to create the most consistent shape, but I can't help but wonder if the outer edge is actually causing downward thrust. My rails were purely top and bottom. EDIT: Also should probably finish watching before commenting... I was also considering TPU - it might not be able to handle the same loads, but is less likely to self-destruct. I'm just not sure how much it would deform. Could be interesting if you could get it to deform in a way that increases the angle as it speeds up. MIT patents are a pain... It makes sense, but would hinder experimentation.
You have me thinking there, I remember Koenigsegg came up with a carbon fibre rear wing which mechanically deformed to produce more downforce at higher speeds - clever because they saved weight compared to other super car makers who were all still using hydraulically controlled rear wings. Maybe there could be a clever blade design which takes into account its flex to mess with the geometry, but I'm not sure TPU is the answer anymore as I've since seen feedback suggesting it's too flexible. Need some other middle-ground material, harder than TPU but softer than ABS for example.
@@STRIKINGFPV yeah - test print I did in tpu is super floppy. Might get pulled straight with enough RPM but probably wouldn't give very stable flight. PETG might be too weak. My metallic gold/copper PLA was slightly more 'rubbery' so might be worth a try. Need to get my hands on a faster brushless though - everything I've currently got is slow stepper type stuff.
@@PyroSAJ Have a quick look at @willitmod 's latest video with the newer tri-loop, he used Silk PLA which was quite springy, and flew a few good rounds around his place. I'm tempted to grab a roll, myself.
I have printed 5" (50x3) version from ASA and tested them inside my apartment. They seem to work pretty well for some basic hovering and wobbling around. Noise profile in BBE seem to be quite decent, and they are not louder than my usual props (maybe a tad quieter, but hard to say without a meter). This is definitely promising, great job!
Daring man to test a prototype 3D printed prop indoors, in your apartment no less! I'm glad it didn't explode, and glad that they worked relatively well for you 👍.
@@STRIKINGFPV I have a relatively large hall with almost no furniture ;-). Yeah, I was little worried about the props simply exploding, because they are incredibly thin (I think that 0.4mm thicker might be better). Unfortunately it is -6ºC outside, so no hard punch testing for next couple of weeks... What's most interesting for me is the noise profile. I haven't really done much of a sanding on the surfaces where supports were touching, and I've also lost one or two bottom layers while separating supports on some spots. Yet it doesn't seem to be noisy up to 50% of throttle. What I want to try for outdoor use is either FDM print from some PC blend (I have an enclosed printer), or sent it to SLS (MJF) to get it printed from PA12.
@@MartinHapl Thickness is a tough one to work out - thinner is usually better and I'm going that direction, but of course a big problem is that we're 3D printing so the very nature of FDM is somewhat compromising strength and performance. From those who have tested and are getting good results, I think I've hit a sweet spot, at least for the smaller props. From 5" and up I believe they're not actually thick enough because the blade loading is more pronounced at the larger diameter, so thickening at least nearer the hub will definitely be needed. As for material, @willitmod discovered that Silk PLA is remarkably strong and flexible and got some decent flight performance outdoors, so maybe can give that a go before sending off for some sexy sintered parts. This being said, if you do go with some nylon laser sintering action, try flying without any sanding first, then sand and compare performance. Would love to know if the slightly rough finish does the boundary layer thing and improves performance, hehe.
Very cool! [edit] - Tuned to reduce stringing. My results are the CarbonFiber PLA (Zyltech) printed well, as did the PLA. The NinjaFlex TPU is a no go - the consistency, at this thin, is like snot. I could not efficiently create a Fusion360 part, but made a hub to fit my DJI Mini, imported the 40x3T and 50x3, cut out your hub, and combined mine into it. Printing now. I am currently printing V2 TriLobe [edit TriLoop] (yea, that is better than Tri-Blade) with similar filament that 'Will It Mod?' used (that silky shiny PLA) used. Although, I am using a 0.2mm nozzle. I haven't mastered the settings to eliminate stringing so a little bit of clean-up. This is on a Creality-10S w direct drive (MicroSwiss). I have a stock DJI-Mini that I want to try these on. I will also print with NinjaFlex (no problem with 0.4mm nozzle, haven't printed with 0.2mm), and I also will print with Nylon (prints great for me). Lastly, I'll try some CarbonFiber PLA (works very well with 0.4mm nozzle, we'll see). I have ABS/ASA, too, but don't have an enclosure. I'll report back.
@@STRIKINGFPV Agreed - first, I have to say I envy you FPV pilots! The CF-PLA is my fav. I have been spending time creating a hub model for my stock DJI Mini, importing your TriLoop, cutting out the center and merging the two. I, of course, have the free version of F360 and the TriLoops have a lot of facets and takes me a long time to convert the mesh to solid. When I get them all printed and mounted, I'll try and fly it - it has been raining this week in San Diego, CA.
@@truegret7778FYI in my latest video I also since the release of the STEP and F3D files so you can more directly modify the design and change things - should help you out with your experiments 😉
@@STRIKINGFPV Funny thing - I downloaded from the V3 pack from Thingiverse yesterday, and did not see the F3D files. Just downloaded again and they are there. Thanks! BTW - to add to your responses to the question "tri-loops don't work on planes, or why bother" .... because as hobbyist/enthusiasts, a design does not have to be practical, it is "because we can". I love what you have done/are doing, and thank you for your efforts. TY
Sounds like the perfect application for resin printing, will just need to get the right resin mix which shouldn't be too difficult. As for patent, printing for personal use should be fine :)
Oh resin is definitely the way, but I don't think anyone's found or at least have yet shared what the best mix might be. Then again, I'm not scouring the internet for answers that aggressively. Perhaps I should, haha.
@@STRIKINGFPV The couple of informative channels I have come across recommend starting with 30:70 mix of flexible:rigid and fine tune from there. And it works for the undemanding prints I do.
Forward lift is likely increasing because the propeller rim spinning is similar in profile to a frisbee-or a wing leading edge. I have been wondering if you get even better performance by ducting these props…
subscribed - definitely keeping a close eye on this one!! I can't understand how toroidal props work (math is not my strong suit) but if it turns out to be more efficient it will revolutionise transport and wind energy generation. Looking forward to testing on my DJI Mini
If you want to experience something really amazing, make a propeller in the shape of a Moebius bottle. A narrow one of course. Any further sound reduction will have to come from making quieter motors, and the lift will be insane at all angles. The thing that is really nuts about that sort of design is that it is not only nearly silent, but it also eliminates almost all downwash. It's a far better design than any of this toroidal stuff. To be clear, you don't want the entire Moebius strip to be coming from the hub. In fact you want to eliminate the hub and attach it directly to the shaft so that equal parts of it are on either side of the shaft. A hub will just get in the way and create unnecessary drag (cavitation in water). You want both the cross-section and angle of attack to be constant throughout the entire bottle. If you do not, you will get aerodynamic stalls at certain angles. If you have the shape of the strip constant throughout, a four prop unit will fly the same no matter what the attitude of the craft is. A moebius bottle design requires four props to be stable. Two or three props will just result in the thing flipping over as you apply throttle. It should be noted that we are still basically beating the air into submission. It's not real flight as the birds do. We are going to need several million years of evolution to do it ourselves, and a heck of a lot more science to accomplish it mechanically. At this point, we're not even close. And no, I'm not talking about a Klein bottle. That is not the same thing as a moebius bottle. A moebius bottle can't hold any amount of liquid, but a Klein bottle can. Also, a Kline bottle can not be made uniform throughout the entire thing. While interesting, Kline bottles do not have any useful aerodynamic properties.
Hello. For efficiency, monoblades are efficient too (but have a caveat i can't remember). Would be interesting to see a monoloop too :-) I was thinking about your symmetrical profile : maybe the "following edge of the loop" needs to have another angle than the "leading edge". steeper ?
Oooh, I've seen some weird monoblade designs in the past, so it's like a single blade and then a weight on the opposite side to keep it balanced right? I can't imagine how weird it would be to do a mono-loop toroidal prop, that would be craziness, haha. As for the having the following edge of the loop being steeper, I was actually thinking about it being a longer blade which sticks up higher into the air stream but at the same angle, though the more I think about it the more I wonder if a steeper angle would also do the trick because of how the leading blade has already partially "eaten" the air before the trailing blade got there, lol. Either way, this is more relevant to the bi-loop design, since there's no loop intersection. Something worth thinking about, definitely
We need HQPROP or gemfan to make some of these. Dalprop too. Hope you get more subs and keep making good content. Try some HQ 4x4x6 on a typical 5" drone, if you are interested in a quiet prop
I had really shallow 6" props on my Roma F6 and they were nice and quiet, but didn't quite have enough authority and thrust at full throttle so went with a more traditional blade pitch in the end. I think it was like 6x2.5 vs 6x3 - there's even a 6x3.5 I'd like to try for lifting heavier loads, potentially, hehe
Increased lift in forward flight is called "translation lift" in helicopters. It's understood to come from escaping the downdraft of the rotor and flying in "clean air".
Yes yes, I've learned about this as well, just that it appears to be more pronounced with the V2 toroidal design, as opposed to regular props, which I found interesting. Probably something to do with the upright loop edges becoming more aerodynamically relevant during forward motion, but hard to know without doing a fluid simulation I think,
The blade should transition to past vertical fully out and the vertical helix will taper outward as in a vertical helical curve. Also close to center you need a twist based on radius. The best first mod on the MIT HELIX should be oval. Second mod will be over vertical pointing in an elliptical outward curve in the furthest radial extension. Basically the tip extension should function as a conical turbine extension and be helical prop more central. The issue is drag vs thrust on the radius. I have been swimming helically for years using my hands. The issue will be seamless transition from helical thrust wing to conical blameless turbine as you progress outward and how much you do this. In swimming you can feel this transition in your hands as you feel the pull on your arms change with hand motions traveling in a figure 8 pattern.
True, guess I'm still trying to support my FDM brothers who've managed to get airborne. And obviously myself, eventually 😅. Will consider doing an SLA/SLS only design at some point
Hey man these iterations are really good! Excellent explanation too! I'm an engineering student from the UK and I'm trying to replicate or rather design my own toroidal prop design. Im currently inspired by the sharrow NX toroidal propeller and im attempting to recreate it! so far to no success... I tried doing a similar method to yours with the rails but with coils to include the 3D geometrics but I think I'm going the completely wrong direction aha. Don't suppose you could do a tutorial in attempting to recreate it? also, another challenge might be to attempt to recreate the CX-1 toroidal prop it looks simpler than the NX version but its harder than it looks when I'm trying recreate it! Thanks so much, dude! Again great work!
Actually I've been planning to do a tutorial for a while now, but just wasn't really happy with my file layout, seemed really messy so it would've been a massive headache for both me and you to try replicating, haha. In my latest video though, I do announce the release of the STEP files and my plans to finally do a tutorial on my design method - it's certainly not the best way of doing it, but it works alright and I'm sure more inspired and talented engineers can improve upon its main concepts.
My 2c and sorry for the "backseat designing" but I feel the wing should start almost vertical at the hub and gradually transition to a shallower angle of attack... finishing totally horizontal at the periphery, and then working back up towards a steeper angle after the transition. This is definitely NOT what the MIT design does, but it is quite close to the Sharrow boat prop design. Conceptually.
The outer edges of the props only create a bit of lift in purely upward relative motion, but creates quite a bit when in a diagonal relative motion Consider moving the toroids away from the center, and using a bar to connect to them
That could well be why @willitmod observed the increased lift during forward flight. I could maybe reduce the size of the tips, which might be able to resolve that effect, but maybe it could be a feature advantageous for forward cruising.
I don't have it on video but I did a roll in my lab with the very first set, line of sight. Great to see so much interest. The tribade first flew on a 5in quad as a proof of concept and I experienced similar struggles and successes. Thomas Sebastian lead the design with an intern and I worked on getting them in the air. SLA did better on the stand but I found them to be too brittle for real world temps and conditions.
Hang on, so you're part of the MIT team that worked on this? I think I have many questions, but not sure where to start. Also, I hope you guys don't mind us messing around with designs and doing this whole mass prototyping thing 😅. Did you have much input on the design or do you have much insight or recommended shapes or design methodology, by any chance?
@@STRIKINGFPV I am indeed a small part of the MIT team. To be clear I am not the designer but I am in the video and was operating some of the drones in my lab. I took part in small geometry changes to help make it printable and different materials to improve strength. I also did drone tuning/piloting, and thrust stand testing. I am actually excited to see what comes out of the FPV/open source community. I am not sure how much I can say and will try and get back to you after bringing it up to the stake holders. The tri-props were V-1 concept and designed by hand. We left a lot of headroom for geometry optimization. The V2 Bi-props were designed parametrically for the sponsor. We have alot of concepts left to explore. www.ll.mit.edu/about/facilities/autonomous-systems-development-facility
@@roboticsjoe3181 Small part but crucial part of the team, don't sell yourself short 😅. That's very cool work you do, and a cool facility as well. Had I grown up on that side of the world maybe I'd be doing something similar. I understand that you're limited in what you can share, but thank you very much anyway for that little bit of insight. Crossed fingers that your stakeholders might let you share more, but I understand if they prefer not to. If you'd like to get in contact, you can grab my email from my channel on the about page (I think). If the powers that be would allow, would be cool to get on a call or something 😅.
Checked tri-50 version. It is still too heavy. Cura says 7g per prop, and regular 5" props are 4g per prop. But bi blade version is much lighter, it's good and ua printing now. As for tpu, what i found with original 3.5" version: after some RPM they just collide and swing around motor :) for me they worked for hovering, but a bit more throttle and they turn into a mess :)
What sort of TPU did you try? The hardest I have is A95 and I feel like that would not be enough for such a thin print. I've been thinking of getting some D58 for other projects and maybe that would be good enough for these as well.
We can 3D print a mold and inject that with resin. I have done this with two part silicone to make custom gaskets. I can't figure out how many parts you are going to need but it should be possible. For another project I plan to make a mold that was a tiny bit over sized out of polysmooth. Poly smoothe is smoothed with isopropyl alcohol. It looks like blown glass when you are done. By sanding the mating edged I would remove the rounding at the seams caused by the smoothing process. You could just sand and paint it to get a smooth mold. Bolts right through the center of the loops will hold it very well. You could also reinforce it with fiber glass. I have some Kevlar roving that could be put inside the molds. Normally yon want the element of a composite that are strong under tensile load on the outside but when it is this thin I don't know how to do that.
That sounds cool, would love to see it on a plane as well. At that size I'm concerned about the blade thickness, since others have commented that the larger sizes seem to flimsy - I'm hoping my next generation will fix that with thicker profiles at the hub.
@@STRIKINGFPV I actually tried the V2 bi toroidal propeller and it worked great, when close it sounds like a loud hairdryer but it actually is much quieter and lower pitch when I fly farther away, thrust is also great but it takes a while to accelerate and decelerate
Got a new sub here. Awesome job on the prop designs. I think the tpu idea is great on the tri-loop version. On the issue of deformity, you could try to add a ring on the circumference of the propeller. Basically connecting each vertical section of the loops. In theory, that would keep them from being able to stretch apart, and keep their overall shape. A quad loop version would also be interesting to try.
There have been a number of good suggestions regarding improving rigidity for TPU, but the more I think about how it deforms under heavy torque the more I think we'll be losing out to increased weight, which then deforms more due to torque, etc, becomes a vicious circle. I think the solution is more along the lines of a more rigid material, that's still flexible. @willitmod actually found that Silk PLA is really bendy and had some great new flight footage with that. Then apparently people of the resin world can mix regular and flexible resin to tune the flex which is so cool.
I think that this loop blades will come to their full potential when used for vertical wind turbines. Just remember to put two Frisbees on both the top and the bottom.
Completed printing PLA versions of the tri blade props. Weighted them and they are within .01 gram of each other. Havnen't tried flying them as it's too windy, 30mph gusts outside. In the mean time tried printing Nylon versions but they didn't work so well. Now in the process of printing some with clear PETG and they look promising. Will try to fly tomorrow weather permitting. I guess the best place to report results is in the comments here?
That's interesting that nylon didn't work out, since nylon is one of those unicorn-y materials that one would expect to do well, assuming you've got your print settings dialed-in and the filament adequately dried. It's one of the reasons why early on I settled with PETG, since it was a little less finicky (but still finicky) than nylon but also quite strong. May I ask more specifically how the nylon prints failed? For results, feel free to comment here, or like upload your own video and tag me, since I'd love to see flight tests and it's just weird and fun seeing my props working on other people's drones 😅.
@@STRIKINGFPV regarding printing with nylon the main issue was that the trailing edges of the prop were warped and uneven. The prop also seemed to have too much flex to work but that is just a observation at this point. I did dry my nylon for about 8 hours at 55c. I'm going to try again later once my PETG prints are completed. Have been doing additional drying of the nylon in preparation for that just in case that is the problem. I will let you know if I have any success with that material. Also thinking of printing with some lightweight PLA that I have laying around. It's supposed to be as strong as normal PLA. The surface isn't as glossy/smooth as normal PLA but don't think that will matter much since the layer lines are present in the prints anyway.
As this design is right now, it is not moldable with the 2-part mold that is typically used to manufacture props. I think it can be modified in a few areas.
From what I've read about injection moulding and having seen in person actual moulds of various items, I do believe that it is more or less impossible, certain for the tri-loop design. The bi-loop may have potential, if done in a split process, perhaps, but the more the shape is refined the more complex it would be to manufacture I think. This could well be part of the challenge, in fact, now that I think of it, maybe the next step for the team is to develop a practical way to mass-produce props of this design (and probably patent said method, which is also fair enough).
Aero engineer here, I was wondering how it would react if you were to design the prop to have the blade rotate to a horizontal non cambered aerofoil at the furthest point. Rather than having it go vertial. As im just thinking there could be some weird aero effects caused by the portion of the blade thats tranistioning between main lift generating secion of the arc to the verital edge section of the arc.
I was wondering about this and I also made a mention of this in my latest video, but my general concern with that idea is that I feel like it then results in creating a blade tip, which is sort of what we're trying to remove? But either way, all ideas are fair, I'm not sure I'll try it out myself, but hopefully more people will get a chance to do so as more people start to design their own. Hopefully I can help with that when I release a design tutorial.
That's the big question mark, how much further out do I want to "delay" the "uprightening". And can I butcher the language regarding toroidal prop design more 😅. Have to think about that for the next iteration, absolutely.
I don't have any ABS around to give that a shot but maybe someone else does. Print a pair from ABS then Vapor smooth them to get a smooth shape to test with. I'd love to try to print and fly a 5" prop.
I do dig that idea, I completely forgot about acetone vapour baths - feel slightly ashamed because back in the day I used to print in ABS for motorcycle parts, but the most exotic thing I print with nowadays is PETG-Carbon.
I think you need to make the very outside profile have an angle so its a lot sharper and decrease the drag. atm the vertical profile will increase drag at a minimum when you are turning
I've considered angling it inwards and outwards, but it always negates one of the joining edges in some way such that the best thing to do for now is to just shorten it much much more which improves the blade angle further out too. Check out my latest post and design where I've done this. Still WIP and not all the sizes are uploaded, but getting there.
The design is very interesting, I'm trying to use this design for computer cooling. The standard fans have an inner diameter of 110 mm / 4.33 inches and an outer diameter / housing of 120mm. It would be great if these fans could also be used for PC water cooling and more power could be produced at a lower volume. I'm trying to adapt the designs at Thingiverse and make a fan like this. Many Thanks for your inspiration and also The Video.
Building it is one thing. But _optimizing_ it could be a major challenge unless you have access to desktop computer with seriously high-end computing power (maybe!) or better yet, getting time to access a real supercomputer. Reason: the mathematics in propeller blade design is extremely complex, to say the least.
Have you ever designed wings before? There is a lot of science that goes into the shape and thicness of the foil, I would think it would take some incredible math to just understand the most efficient straight propeller designs, in order to meet the needs of what it is designed for. But what you are dealing with here is not a foil on one axis, with the center being that which will be fastest, but also it will slow down as it generates the thrust, then because od the blade curl under, there is going to be pressure from the outside loop, and how that air is moved over the blade will mean everything, but then you have to consider the backside pressure which directly affects that flow speed and direction on the interior. I like what you are doing here, but you could look at this like a fancy paddleboat vs the MIT thing which is super advanced research and mat5h going into calculating the speed and density of the fluid of a screw on a modern day submarine. Fluid dynamics is fascinating, and perhaps you can gather the relevant data, but I would say the person that won that award has probably been hard at work on that for quite a while. The patent and implications of this technology are huge! Hopefully you and your community will be able to derive something producable. I would guess it would need to be some kind of casting process though. Or maybe liquid printing? Not sure. They do have one of these for boats and they cnc an alloy. OFC it is a much more aggressive leaning loop, for more thrust at lower speeds.
In future iterations I think I'll probably end up researching more traditional blade/wing designs and try using them as loft profiles, potentially. The big headache for me now is getting good enough at designing in Fusion 360 such that we can simplify the design process so that more people can try their own versions and see what really sticks. Would love to pick the brains of the MIT guys somewhat, maybe see if they can offer guidance, maybe even share their process in the spirit of open source (despite the patent 😅).
@@STRIKINGFPV OK well, I subbed to hang along. I notice there is a playlist for MIT fluid mechanics, and as you should know air is just a less dense fluid, so plenty to research out there! Not so much about a 3-d application of it in a propulsion sense. Fascinating stuff!
It is a 2 dimensional thrust vector over 5 Positions of thrust counter rotating 360° from 10 angular momentums = 24 Dimensions for 12 Attitudes Drags 2/5√360√10=24 Five blades, not three
This is super interesting. What if instead of taking the leading and trailing edges vertical, they become horizontal and the upper edge on the front becomes the lower edge on the trailing half of the loop? Does that make sense? That would mimic the shape of props now that reduce drag on the tips by flattening out.
Yes, so a more horizontal profile - I've considered this and I do also outline in my latest video why I probably won't be trying that soon, since the horizontal edge profile may end up creating a wing-tip, which sort-of negates the whole concept of eliminating the wing tip by looping it. I'm also uncertain of the geometry that would be generated between the leading blade's trailing edge and the trailing blade's leading edge (now that's a confusing sentence, haha), I feel like it results in just a single blade with a hole in the middle.
You might be able to compare different designs simply on the basis of hover - carrying known weights. Until people compare measurements, not just personal impressions and videos of things without scale, I do not see you ever getting the global prototyping and collaborative design world you think will help. Share models, share measurements on prototypes, share detailed recordings of precisely reproducible tests, share the algorithms, share the flight data and control signals, inertial measurements, and flow measurements. I think you can use that laser air ionization to inject tracers into the flow at precise times and locations. The laser focus can be programmed to match the needs and scale of the test. Tethered hover tests (known weights) and local power, will allow testing for hours or days, not limited by batteries. Fewer parts on board - focus on the lift and small small control changes. You do not have to make big movements to test, You just need finer and finer measurements. A whole test rig might fit over a table top. Yes it matters have fast you print. If you check laser cutting, plasma cutting, 3D thermal printing, and many other 3D fabrication methods -- they ALL are art, not science, yet. That means small changes in the way something is "printed" make a lot of difference to surface, strength, internal acoustic resonances and strains. Flow is something that goes down to atomic scale. You can modulate flows to make them easier to measure and easier to modify and control. If you tether and do not have to worry about weight, then you can use powerful computers and sensors first - and iteratively converge to high value and interesting combinations (designs). You are doing good things. I suggest you add $Thanks so people can support and encourage you. If you have specific needs tell people. Be sure to write more, because the words are what the search engines find, not what is in the video (now, maybe one day...) Richard Collins, The Internet Foundation
That's a lot to absorb, but you are correct. I think at this early stage though part of the main challenge is not so much the fine design changes but more the print quality, as this type of development is heavily reliant on consistent and good manufacturing, which is still difficult and basically impossible for FDM, so part of this is to get people excited in being able to print their own and test them out to begin with. The people with access to higher quality equipment and finer resources are the ones who will really take this and run with it, in fact I've had some university students mention to me as well that they'd love to work on the concept more, asking for the design files which I've now released along with my latest V3 tri-loop and V2 bi-loop designs. And in the future I will also release a tutorial on creating the design in CAD. At that point, with more people able to modify the design themselves, those people would be able to do more intricate and meaningful testing, and I have hopes that they will share their findings with all of us. Or maybe this will all fizzle out when the hype dies down 😅. It's the internet, after all, and we have limited attention spans sometimes. Plus I don't do this for a living, haha.
Nice job, but it might just be me, but I think there is a principle error in the design where the loop blade the front and rear part are in the same plane, i would make the rear part below the front. This way you can easier get a more constant shallow going to 0 AoA over the tip, instead of going vertical at the tip which is just pure drag.
This could get very interesting in sets of counter rotation blades. Tuning for noise cancelling perhaps? Iterations combining triloop and biloop. Very promising for ductless/ propguardless cinewhoop use.
Yes, I think I didn't emphasize that Johnny's surprise was by how much more transitional lift the toroidals seemed to get vs standard props. I now think that the V2 design's very tall vertical section had something to do with it. I had a feeling that my V3 tri-loop design's would behave more normally, and I believe I've achieved that, having seen the V3s tested by @MoppelMat and flying quite comparably to a regular 5" tri-blade.
@@STRIKINGFPV Could it simply be that there's more blade surface area than on a traditional prop? I watched that video as well, and I wonder if the same effect could explain why he was losing so much lift in turns, because the resulting airspeed over the prop (especially the props on the inside of the turn) is lower, given the lower free-stream airspeed. What I'm getting at is that that prop may be taking more advantage of the free-stream airspeed. Perhaps a prop that is more optimized for hovering would make it more like traditional props in that regard.
@@sthomas6369 Very possibly yeah, but if that were the case you might also expect 5- 6- 8-blade props to exhibit similar behaviour compared to a tri-blade, but I haven't yet seen anecdotes of that type. Would be interesting to test actually.
czcams.com/video/wAXWpmX8gcM/video.html tested 5" bi blades. 1. Flight quality is totally like normal props. Good grip, propwash all stuff. Balance is acceptable, was flying on BF 4.4 default pids and filters 2. Low efficiency probably 50-70% efficiency of good regular props 3. Noise is pretty high, probably higher than regular tri blade, but the pitch is much lower. Maybe this will it less intrusive in the distance 4. Did not explode under around 70% throttle on a 6s 5" quad :)
Your analysis re drag.. A "tricky" part of designing props for multicopters, they are "optimised" for the flight regime of hover- ie, we wold like to see max efficiency for zero blade advance ratio - minimum drag in the rotational plane is a task to achieve. (thinned loop tips are likely to produce lower drag). Then one can redesign for a range of advance ratios - to test for different flight styles from camera ship through to freestyle or race (high advance ratio).. The intersecting loops are doing some complex intersection drag type of thing - that has downsides. A nonintersecting "bi-loop" (or tri) could also be made in VP fairly trivially, potentially suited to full size aviation applications - or is a really aggressive scimitar tip a better choice?
I wonder about the non-intersecting tri-loop as well, actually. I dig the intersecting one because of its overall more rounded shape, so it's definitely more suited to indoor drones with proximity to people and things, but I figure the current bi-loop design is more efficient, so I imagine a similar looking non-intersecting tri-loop would actually perform better, but be a bit more slicey. I should look into simulation actually, I would be fascinated to see what weird fluid dynamics of actually occurring at the edge of the loop, behind the leading blade of the loops and also the intersection points. Must be really weird looking.
It's pretty steep - honestly, even the way I modelled mine is kinda' janky, still not satisfied with how I've done it, but it works. Eventually I'd like to make a tutorial on designing props like these, but I'd like to get a method which works well, otherwise the tutorial might raise more questions than it answers 😂
Hi, one comment : why did you put the external shape vertical? You should try to put it vertical, it would reduce the drag at the external part of the propeller. And seen from the front of the propeller, the back part of the loop would be higher than the front part of the loop, so they might disturb each other less (not sure of that as the flow should be more or less horizontal...)
I was also wondering about this sightly philosophical question 😅. This is why I quite like the term bi-loop and tri-loop, which maybe should become the standard way to reference parts of a toroidal prop.
What has MIT actually patented? My light reading on the topic has discovered that this is not a new technology or design. The previous limitation was materials and manufacturing complexity. These drone up cost, so more cost-effective designs took the lead.
I tackle this in my latest video actually, but I believe one of the novel ideas as mentioned to me by another commenter, is the intersection of the blades in the tri-loop design, which apparently hasn't been written-about before. But I would agree with you in that these props will up the cost due to their difficult manufacturing, and their benefit currently doesn't really outweigh the cost increase I think.
That mass prototyping, experimenting and collaborating thing is the best thing i saw on youtube
This is for sure one of the biggest reasons I have so much fun with, and love the fpv & other open-source communities! When we are able to all put our heads together, innovation comes faster, and everyone is able to learn and benefit. (thank you to MIT for showing us this design!)
How everyone is jumping on it. Thats just insane
This is the kind of thing that builds community. Love it.
The more the merrier!
@@STRIKINGFPV thanks for the explanations. Please look at the three blade vs four blade turbo prop difference in C-130 aircraft. I am confident you are aware what to expect, but it blew me away as a mechanic who flew on both. Cheers. You earned my sub.
Congratulations on the subs, and thanks for the mention / shout out! :)
No problem, your testing was awesome and pretty bold, definitely deserves some traffic your way 👍
@STRIKING FPV I appreciate it. New tri-loop props printing out tonight in PLA+, testing tomorrow. 😀
Awesome, glad to hear you’re getting some of the recognition you deserve, great work man
I printed and tested a set of these. Some minor drawbacks but lots of potential. And they look super cool. Thanks for sharing!
Glad you like them! V3 and V2 are out already if you haven't seen, along with a new video explaining more of the concept with questions and suggestions from the community.
Once I can make a 40mm prop, I’m going to print it with some tough resin! Can’t wait to test 😎
If you checked earlier than before I uploaded, there's a 40mm version of my design which might work for you. It's not perfect, it was scaled around from the 2.5 inch version I remade, but it might be viable? Let me know!
use tenacious resin it's a tough but slightly flexible it's awesome
@@MrDangle1125 the tests that I’ve done so far using Siraya Tech Blu have been too flexible. I think the challenge will be making them stiffer
FYI: Latest video featuring frequent questions and suggestions is up:
czcams.com/video/pjZaGHKQB8Y/video.html
Hey all, so I've finished updating the tri-blade tri-loop toroidal designs so it ranges from as small as 40mm all the way up to 6" and I'm going to have to stop there for the next few weeks. Looking forward to seeing tests and hopefully more designs will pop up from other creators and designers soon. Just check the same Thingiverse link. No time to add more bi-blade sizes, but I hope that's not an issue. Maybe you guys can play with scaling it up and down, or someone can remix them with different hubs, etc.
I'll still be commenting and replying, just won't be designing when on the road. Thanks again for the likes, encouraging comments and subs, and see you all again in maybe a couple weeks.
EDIT: Ooh, ooh, apparently the newer design is lighter, produces more thrust and draws fewer amps than the last time! Check out the short video from Vlade at @QEDFPV:
czcams.com/users/shortsTVZxl3116OM
Bi-blades/Bi-loop 5" got airborne courtesy of Vladimir over at @maxbl4 :
czcams.com/video/wAXWpmX8gcM/video.html
Also, Johnny on @willitmod has some fantastic flight footage using the new design printed in Silk PLA which has fantastic material properties: czcams.com/video/UNL8KXdAggc/video.html
could you release the fusion360 files? That would be awesome. I would like to do some testing and modife your versions =)
@@davincifpv3842 The project file or step file is a huge mess right now, compared to stuff I've done in the past - in the same way that I'd love to do a proper tutorial, I'd love to eventually release a step file when I've got a better, more consistent methodology that won't drive people up the wall wondering why the loft doesn't work or the why the cut command is glitching 😬.
I tested your first design on my 3.5 inch custom cinewhoop and it flew pretty good for the FDM standards of a printer, looking forward to testing these! Will surely do another video, thanks for taking the time to design these!
That's awesome, looking forward to see results with the newer design!
I’m one of 400+ new subscribers 👌 cheers mate awesome ,glad I’ve found ya 👏👏👏👏
Awesome! Thank you!
It’s great to see a project I helped work on from 2016-2019 finally go public. It honestly not a new thing, but we were a lot more comfortable going public after our patent went through in 2019.
Also to clarify about MIT designing it, not everyone that’s worked on it is from MIT, it’s only because I worked on the project using their campus and their equipment, we had no choice to credit them for it, but in reality it’s a pretty big collaboration with lots of individuals from different universities.
I hope you don't mind but I've included your comment in my latest video just so that more of the community realise that even on the "MIT" side of things it was a tremendous group effort, kinda' like what we're trying to do now.
@RoboticsJoe also mentioned his involvement and I asked if there was anything you guys were willing to share, I'm guessing that's more of a no, understandably, but would be cool to get more insight into what went into the project.
Congratulations and thank you for the efforts you put into this concept already!
regarding the velocity-dependent lift:
in the low-speed regime (as in "very sub-sonic") the airflow over a prop blade traveling forward increases with additional speed, which, being an airfoil, generates more lift.
My wife and I are blown away by your absolutely perfect English and tone of your voice . It's better than Elglang , American and Australian English. What are you language influences. I'd send every kid in America to learn how to speak perfectly from you .
Haha, funnily I have English, American and Australian influences going on. I'm half Australian, but my dad spent a lot of time in the UK so he sounded mostly English, but television and schools I went to were predominantly American/International sounding so my default neutral accent is mostly American with a few English pronunciations here and there.
Really cool work. I personally feel the two blade/complex props will be a more viable option. Another possibility is to avoid trying to get the blade tip to curve to vertical and then blend into the other blade behind it and instead just make a forward swept blade that's standalone then put a back swept blade in front of it and have their blade tips close enough to connect with a short connector. Not exactly toroidal, just the front blade supporting the wing tip of the forward swept blade tip behind it.
This was suggested by someone else I think in my last video as well, basically having the blade tip being horizontal instead of vertical, but I believe the whole point of the toroidal design is to effectively not have a blade tip, since wing/blade tips are where the most turbulence is created, which contributes to the noise created. A horizontal tip would end up being more like a regular tip, compared to the vertical.
I'd like to try the idea regardless, might just make a strange prop with no other real benefits, but first I think I might try reducing the height of the vertical at the end, which might mitigate the issue of the blade getting steeper further towards the edge.
@@STRIKINGFPV you should think about minimizing the weight at the outer diameter as much as possible in future designs. This was the one big disadvantage I found in my testing. Too much weight at the outer rim hogged amps and made them very imbalanced. Otherwise I liked everything about them. Quiet, noticeably thrusty and much more safe.
Evade the patent game woohoo that never happens. Visit inline skates and the Rollerblade history.
@@dutchfpv7010 Yes, that's definitely what I've got going on in my head, I'm thinking of reducing the height of the vertical edge, which should hopefully also result in shallower blade angle closer to the edge. In theory that will also reduce the weight near the edge, and give these props better response.
In theory 😅
Air plane designers have had lots of iterations designing blended wingtips which didn't really adversely affect cruise drag, reducing tip vortices when slow and heavy - around airports is one thing (safety), getting lower drag numbers for cruise is important... This is probably where this design is at right now, fighting the design optimisation between blended wingtips and scimitars.
I don't know where your channel is going to be at in a couple months, but keep it going, you're a natural.
I appreciate that!
"for reasons"
"because of how rotation works"
This kind of science really speaks to me
I pride myself on eloquent speech when in the moment 🤣
For those wondering, blade tip airspeed is higher because it's travelling/sweeping across a longer distance in a single rotation compared to say the base of the blade at the hub. Hooray reasons and how rotation works!
I had some ideas for improvements you implemented. love to see that!
I posted some of them and some accured to me later, but it looks like you had the same ideas :D
I think the improvements you did are really a good step forward!
I am really looking forward to how the design will improve over the next generations and might become better than traditional props in many ways.
Crossed fingers that we get there, but much like various developments in FPV's past, never know if something eventually falls by the wayside. I hope these props go the distance, but there's a good chance that they won't either. Gotta enjoy the journey though, haha.
“Mass prototyping” I love that word
I’m diligently sharing this everywhere I can
Mass testing, mass prototyping, when we want stuff done it makes sense to be all hive-mindy, haha
This channel gonna blow
Here's hoping ?
CZcams suggested this video for me to watch. Most likely because this same subject was in a video on Major Hardware's YT channel. After MIT came out with their findings, Major Hardware guy printed one of these to try it for a PC cooling fan. So I speculate that some of your 400 new subs are like me and also sub to Major Hardware and our interests are piqued lol. I enjoyed your video today and look forward to more of your creations. Have a great day.
😅 same alghorithm victim here. I saw the video of the pc cooling fan and yesterday I get the suggest of yt for this channel and now I want to repair my 3D printer for an experiment…
All hail the algorithm I guess, haha. Cheers for stopping by and glad you dig it! Won't be posting for a bit so feel free to explore the back catalogue 😅
Can’t wait for HQ selling such amazing loops.
Found you via Will it Mod, this sort of design has grabbed lots of attention. In the late 1980's I was using 12" multiblade props with a ring on the tips. Crashed many times, props survived, everything else broke. Mechanical gyros suck.
Oh crazy, so they were like those plastic toys but actually on an RC plane? 12" is quite large for a prop, but I suppose back then materials were heavier so larger scale was the thing. I remember as a kid my dad had an RC glider which had a brushed motor with gearbox (folding prop blades for when the motor was turned off), a chunky NiCad battery and the whole thing was balsa frame covered with thin (maybe 1-2mm) plastic. Very heavy actually, but at its scale light enough to fly. Wouldn't want to get hit by it, not like these EPS foam PNP kits coming out of China these days.
Now that I think of it, maybe that glider we had actually had a 12" prop 😅.
I'm printing 5" bi blade version! Looks great! :)
Ps, thanks for new design! I'm also excited to try this and the whole collaboration thing! :) You spelled my name great, i know how hard it is for non Slavic people
I have a few Eastern European friends here and there, and I enjoy getting pronunciations right if possible 🙃
i think everyone needs to consider the old school round circle around a 4 blade prop its an old design that every quad used in the beginning it works its quiet and doesn't cut you when it bumps into a hand or face.
I remember having toy plastic helicopters like that, hours of fun, haha. Not sure how those would stack up, though, because a big part of high performance FPV drones now is prop response, and having a ring all the way around the outside would result in a lot of added and aerodynamically useless mass which would lower prop response.
I think the toroidal prop could possibly end-up being like a middle-ground between open props and the old ring ones that you mention.
This being said, it would be worth doing a comparison between all three, definitely.
A couple of additions from fluid dynaics in submarine propeller blade designing:
On the forward spinning half loop (meaning the "quick vertical" leading (top edge) add "Barnacles" meaning bulb-like bumps in an eroded cone (barnacle) shape along the top edge. Add the same to the rea-half-loop's trailing edge, facing down.
Additionally, add micro dimples to the surfaces of the loop, like a golfball.
What will result is a better pattern of the prop's eddy wash.
You could add internal piping from a leading-to-trailing barnacle.
but what you really want to evaluate is the eddy wash.
Thank you so much sharing. I will print them and try them out and report back to you. Again thanks.
safe travels. Great work!
Cheers!
First time I've heard of these props here, and I really like the idea of it being quiet 👍👍
And I can't help but feel like you're destined to use such props because your channel name seems so appropriate 😅.
Just an update from my short testing. First of all was able to successfully print these props with PLA, PETG and Nylon. My testing was with a 3" Tyro 89 which is a cheap ass quad I know but it flies well, at least for me, using a default BF tune. Testing results were the same for both PLA and PETG. In both tests I was able to achieve flight and both sets of props held together just fine with no apparent deformations, stretching, etc of the props. Hover flight exhibited wobbling/stability issues that were controllable sort of. This was also true for small slow changes in direction. However normal paced flight was pretty much uncontrollable. Motors and battery were very warm to the touch at the end of the flight. When using normal props on this quad the motors and the battery are dead cold at the end of the flights. Flights were conducted in angle mode which as I am writing this I am thinking that could have exacerbated the situation as the quad was perhaps trying to self level itself instead of depending on my inputs, don't know for sure. Perhaps someone could chime in if they had seen a difference in stability between acro and angle flight modes. Finally didn't test with the nylon props due the poor results from the first two sets (PLA and PETG).
Like one of our earlier testers, they had crazy wobbliness from angle mode, but acro hovered fine - also, many people have noted that PID tuning is most likely required, with some testers lowering their D term to good effect. This being said, have you tried the V3 props yet? @WillItMod tested those and liked how they flew, they seemed the most normal-behaving design compared to the earlier two generations.
@@STRIKINGFPV No I haven't tried V3's when did they come out? Are they on thingiverse?
We've been doing a lot of quiet prop designs ourselves and a lot of people have sent us your video. Absolutely enjoyed both videos! Looking foward to see your own test results after you get access to your 3D printer
Cheers for the kind words, hoping we can all make bigger strides with this, or die trying 😅
Do you have any quiet props? What do they look like?
I don't even have a drone but for some reason I got the MIT stuff recommended and now I'm down this rabbit hole of people experimenting with toroidal propellers on drones, it's really cool to see though how the community is in this experimental phase right now, just trying out all sorts of versions of the MIT design
Just subbed because of the prop and possible use in water pumping efficiency. Three decades ago I told my students young folks had to sort out the problems of the future. Well, I was right about that. Thanks!
As a drone pilot and hearing that its quiter and your doing a great job. So that's why I am here.
I loved to see such experimenting. With FDM printers have you considered Polypropylene? It also has glass-fieber composite types. Its an interesting material, more flexible than TPU, less fragile than a harder neon. Layer adhesion is exceptional. Sticking it to bed can be tricky, some manufacturers' product warp a lot, but I'm satisfied with the one I bouth from Amazone, called Braskem. What I saw from tests that these are heavy and need quite some torque to react for quick stability maneuvers, so maybe larger diameter motors with lower stator would be more beneficial.
My harebrained concept. I'd mod the two toroid design. View top down, rotation counter clockwise. Draw a line from tip to tip through the center of the hub. Cut the toroid tips. Leave the trailing half, and remove the leading half of the blade. Then duplicate the trailing halves into a 6 blade prop, with the blade looking like a forward facing scoop. Make the prop from light rigid material like carbon fiber for minimum deformation at high rpm.
All performance testing should be done on bench mounted stands to compare thrust.
more lift at speed = ETL. Effective Translational Lift. A key aerodynamic of helicopters that I've always wondered the reason why wasn't really a noticeable effect on mini quadcopters. The effect is because the drone is sitting in its own vortices until it gets enough horizontal speed that each rotation of the prop is finding "clean air". I suspect it's due to the thrust to weight ratio of the drone on these props is quite low. He does appear to be flying very slowly compared to what I'd expect from a drone of this size. This suggests the props he's using are not very powerful at all. Props to you (lol) for designing them but I doubt they are anything close to aerodynamically ideal, and of course the 3D print is going to be heavy and rough compared to any injection-moulded nylon. We're just getting started on this journey. I'm really glad you knocked out a testable design so quickly, and can't wait to see where this goes.
Or is it creating lift from the drone's forward motion?
I am printing polycarbonate, ASA, Nylon-G, Nylon-X and will print a set and test on my Phantom 4.
Sounds great, let us know which material works the best!
I did a roll on same day, check my next video :) the first vid had wrong pids. I was worried about bad balancing of props, and added too much filtering. But after checking bb, found there are no noize problems, cranked up the pids and got it flying pretty stable
Wkd update. Thanks for sharing.
Patents are not meant to block research. If you can improve the design, you can also file for an improvement patent.
I think we're all just very concerned because of how patents are often used unfairly, more-so in the software space admittedly, but it's something to be cautious of. That being said, I don't honestly think MIT would try to stop us from messing around with the concept, I think they'd only step in if a large commercial entity started spitting these out with licensing, so like DJI and other larger scale manufacturers. I do touch on this a little more in my latest video.
Thank you, seems it's worth the investigation of the most efficient design and use case. Please CFD this!
Awesome work! We really needed someone who would carry out precise research to improve the efficiency of the blades in the world of small aircraft. The idea on the TPU is interesting, but it makes me doubt, at high rotation speeds as well as sudden accelerations, the elasticity of the TPU could generate instability or latency, in the control of the aircraft .... I would opt for the use of much more resistant materials, at a mechanical level. Of course I'm sure I know a lot less than you about it! So I just hope you can continue with this project!
You're right, some people have already mentioned that the TPU warps too much at high speeds and acceleration so it's a no-go. I've addressed this in my latest video as well, everyone should ignore my past suggestion 😅
@@STRIKINGFPV I'm glad you're continuing the experiment! I'm off to catch up on your latest video right now. I can't help mentioning a few things I've noticed while examining some other users' tests: it seems that this toroidal design is very inefficient at low rpm, both in terms of thrust generated and in terms of noise, while it improves when it reaches high rotation levels. Of course it is a bit unbalanced to compare them directly to industrially produced propellers, which also have a smoother surface. Most likely by printing them with a 4K resin printer, using a good resin, you could have some improvements in aerodynamics...
@@lucamagni99 Oh totally, honestly resin is the only way to go to get comparable results to production props, but I love keeping FDM in mind because FDM, to me, is more the spirit of the maker and the creator, it's still the most accessible printing method for home tinkerers and so being able to produce these props on FDM and have them fly pretty-well (a la @WillItMod's tests) is very exciting, actually.
Let's say we'll leave resin for the serious scientists, but we're not leaving our FDM people behind either 😁
@@STRIKINGFPV I completely agree! From an economic point of view, maintenance, and above all safety in terms of health, fdm printing is undoubtedly much ahead of the resin one. Not to mention that the main reason why I prefer it are the printing times, and you can check immediately if the printing started well! Perhaps it would be interesting to experiment with a print, using a 0.1 mm nozzle, and a carbon fiber enriched PETG filament, to keep the weight down...
Ok yeah I got it. In acro mode it can change input faster so it can correct itself faster, thus better stability. That's a little odd but not entirely unexpected.
I think it's all pretty fascinating and I do like the fact that they emit less high frequency noise, but to be a game changer they really need to yield longer flight times than standard bladed props.
And yep, I agree. Tri-Loop®rolls off the tongue way better than tri-toroid. 🤣 Very nice work on all this, bro. Very cool. Keep it up!
Well, it's weird because in acro, you're only using the PID loop to change the drone's orientation, but it's not actually referencing any absolute rotational positioning in the world. Angle mode, however, is using the accelerometer part of the IMU to determine where "down" actually is, and such if the PID tune isn't tight enough then the angle controller needs to give extra command to correct the situation, but with the bad PID tune it seems to overshoot and flip flop.
So yeah, PID tuning in acro mode is very important before hoping for reliable angle mode performance.
I love where this is going!
cheers !
Interesting - While I have no access to actual drone hardware - I used this to practice a bit of Fusion 360.
My design last night also used 5 profiles - two at the root, two at the leading and trailing pieces, and the last at the tip. What I did though was make the tip still angled.
This seemed to create the most consistent shape, but I can't help but wonder if the outer edge is actually causing downward thrust.
My rails were purely top and bottom.
EDIT: Also should probably finish watching before commenting...
I was also considering TPU - it might not be able to handle the same loads, but is less likely to self-destruct. I'm just not sure how much it would deform. Could be interesting if you could get it to deform in a way that increases the angle as it speeds up.
MIT patents are a pain... It makes sense, but would hinder experimentation.
You have me thinking there, I remember Koenigsegg came up with a carbon fibre rear wing which mechanically deformed to produce more downforce at higher speeds - clever because they saved weight compared to other super car makers who were all still using hydraulically controlled rear wings.
Maybe there could be a clever blade design which takes into account its flex to mess with the geometry, but I'm not sure TPU is the answer anymore as I've since seen feedback suggesting it's too flexible.
Need some other middle-ground material, harder than TPU but softer than ABS for example.
@@STRIKINGFPV yeah - test print I did in tpu is super floppy. Might get pulled straight with enough RPM but probably wouldn't give very stable flight.
PETG might be too weak. My metallic gold/copper PLA was slightly more 'rubbery' so might be worth a try.
Need to get my hands on a faster brushless though - everything I've currently got is slow stepper type stuff.
@@PyroSAJ Have a quick look at @willitmod 's latest video with the newer tri-loop, he used Silk PLA which was quite springy, and flew a few good rounds around his place. I'm tempted to grab a roll, myself.
Very cool, thank you for the explination
My pleasure!
I have printed 5" (50x3) version from ASA and tested them inside my apartment. They seem to work pretty well for some basic hovering and wobbling around. Noise profile in BBE seem to be quite decent, and they are not louder than my usual props (maybe a tad quieter, but hard to say without a meter). This is definitely promising, great job!
Daring man to test a prototype 3D printed prop indoors, in your apartment no less! I'm glad it didn't explode, and glad that they worked relatively well for you 👍.
@@STRIKINGFPV I have a relatively large hall with almost no furniture ;-). Yeah, I was little worried about the props simply exploding, because they are incredibly thin (I think that 0.4mm thicker might be better). Unfortunately it is -6ºC outside, so no hard punch testing for next couple of weeks... What's most interesting for me is the noise profile. I haven't really done much of a sanding on the surfaces where supports were touching, and I've also lost one or two bottom layers while separating supports on some spots. Yet it doesn't seem to be noisy up to 50% of throttle. What I want to try for outdoor use is either FDM print from some PC blend (I have an enclosed printer), or sent it to SLS (MJF) to get it printed from PA12.
@@MartinHapl Thickness is a tough one to work out - thinner is usually better and I'm going that direction, but of course a big problem is that we're 3D printing so the very nature of FDM is somewhat compromising strength and performance. From those who have tested and are getting good results, I think I've hit a sweet spot, at least for the smaller props. From 5" and up I believe they're not actually thick enough because the blade loading is more pronounced at the larger diameter, so thickening at least nearer the hub will definitely be needed.
As for material, @willitmod discovered that Silk PLA is remarkably strong and flexible and got some decent flight performance outdoors, so maybe can give that a go before sending off for some sexy sintered parts.
This being said, if you do go with some nylon laser sintering action, try flying without any sanding first, then sand and compare performance. Would love to know if the slightly rough finish does the boundary layer thing and improves performance, hehe.
Very cool!
[edit] - Tuned to reduce stringing. My results are the CarbonFiber PLA (Zyltech) printed well, as did the PLA. The NinjaFlex TPU is a no go - the consistency, at this thin, is like snot. I could not efficiently create a Fusion360 part, but made a hub to fit my DJI Mini, imported the 40x3T and 50x3, cut out your hub, and combined mine into it. Printing now.
I am currently printing V2 TriLobe [edit TriLoop] (yea, that is better than Tri-Blade) with similar filament that 'Will It Mod?' used (that silky shiny PLA) used. Although, I am using a 0.2mm nozzle. I haven't mastered the settings to eliminate stringing so a little bit of clean-up. This is on a Creality-10S w direct drive (MicroSwiss). I have a stock DJI-Mini that I want to try these on. I will also print with NinjaFlex (no problem with 0.4mm nozzle, haven't printed with 0.2mm), and I also will print with Nylon (prints great for me). Lastly, I'll try some CarbonFiber PLA (works very well with 0.4mm nozzle, we'll see). I have ABS/ASA, too, but don't have an enclosure. I'll report back.
Oooh, would love to know how you got on, what material you liked the most, maybe even some flight footage would be nice to see.
@@STRIKINGFPV Agreed - first, I have to say I envy you FPV pilots! The CF-PLA is my fav. I have been spending time creating a hub model for my stock DJI Mini, importing your TriLoop, cutting out the center and merging the two. I, of course, have the free version of F360 and the TriLoops have a lot of facets and takes me a long time to convert the mesh to solid. When I get them all printed and mounted, I'll try and fly it - it has been raining this week in San Diego, CA.
@@truegret7778FYI in my latest video I also since the release of the STEP and F3D files so you can more directly modify the design and change things - should help you out with your experiments 😉
@@STRIKINGFPV Funny thing - I downloaded from the V3 pack from Thingiverse yesterday, and did not see the F3D files. Just downloaded again and they are there. Thanks!
BTW - to add to your responses to the question "tri-loops don't work on planes, or why bother" .... because as hobbyist/enthusiasts, a design does not have to be practical, it is "because we can". I love what you have done/are doing, and thank you for your efforts. TY
Sounds like the perfect application for resin printing, will just need to get the right resin mix which shouldn't be too difficult.
As for patent, printing for personal use should be fine :)
Oh resin is definitely the way, but I don't think anyone's found or at least have yet shared what the best mix might be. Then again, I'm not scouring the internet for answers that aggressively. Perhaps I should, haha.
@@STRIKINGFPV The couple of informative channels I have come across recommend starting with 30:70 mix of flexible:rigid and fine tune from there. And it works for the undemanding prints I do.
Looks amazing! Post it on printables as well please!
Away from the computer at the moment, but yes I probably should spread it over there, good reminder 😅
Forward lift is likely increasing because the propeller rim spinning is similar in profile to a frisbee-or a wing leading edge.
I have been wondering if you get even better performance by ducting these props…
Or use it for even more lift since it seems to do this well.
Brilliant. I will try in my phantom 3
subscribed - definitely keeping a close eye on this one!!
I can't understand how toroidal props work (math is not my strong suit) but if it turns out to be more efficient it will revolutionise transport and wind energy generation. Looking forward to testing on my DJI Mini
If you want to experience something really amazing, make a propeller in the shape of a Moebius bottle. A narrow one of course. Any further sound reduction will have to come from making quieter motors, and the lift will be insane at all angles. The thing that is really nuts about that sort of design is that it is not only nearly silent, but it also eliminates almost all downwash. It's a far better design than any of this toroidal stuff.
To be clear, you don't want the entire Moebius strip to be coming from the hub. In fact you want to eliminate the hub and attach it directly to the shaft so that equal parts of it are on either side of the shaft. A hub will just get in the way and create unnecessary drag (cavitation in water). You want both the cross-section and angle of attack to be constant throughout the entire bottle. If you do not, you will get aerodynamic stalls at certain angles. If you have the shape of the strip constant throughout, a four prop unit will fly the same no matter what the attitude of the craft is. A moebius bottle design requires four props to be stable. Two or three props will just result in the thing flipping over as you apply throttle.
It should be noted that we are still basically beating the air into submission. It's not real flight as the birds do. We are going to need several million years of evolution to do it ourselves, and a heck of a lot more science to accomplish it mechanically. At this point, we're not even close.
And no, I'm not talking about a Klein bottle. That is not the same thing as a moebius bottle. A moebius bottle can't hold any amount of liquid, but a Klein bottle can. Also, a Kline bottle can not be made uniform throughout the entire thing. While interesting, Kline bottles do not have any useful aerodynamic properties.
Hello. For efficiency, monoblades are efficient too (but have a caveat i can't remember). Would be interesting to see a monoloop too :-)
I was thinking about your symmetrical profile : maybe the "following edge of the loop" needs to have another angle than the "leading edge". steeper ?
Oooh, I've seen some weird monoblade designs in the past, so it's like a single blade and then a weight on the opposite side to keep it balanced right? I can't imagine how weird it would be to do a mono-loop toroidal prop, that would be craziness, haha.
As for the having the following edge of the loop being steeper, I was actually thinking about it being a longer blade which sticks up higher into the air stream but at the same angle, though the more I think about it the more I wonder if a steeper angle would also do the trick because of how the leading blade has already partially "eaten" the air before the trailing blade got there, lol.
Either way, this is more relevant to the bi-loop design, since there's no loop intersection. Something worth thinking about, definitely
Yes, single blade and a balance.
I can't wait to see what you'll do next!
"Getting stuck in trees" is why freestyle pilots always end up sticking with good ole tri blade props
We need HQPROP or gemfan to make some of these. Dalprop too.
Hope you get more subs and keep making good content. Try some HQ 4x4x6 on a typical 5" drone, if you are interested in a quiet prop
I had really shallow 6" props on my Roma F6 and they were nice and quiet, but didn't quite have enough authority and thrust at full throttle so went with a more traditional blade pitch in the end. I think it was like 6x2.5 vs 6x3 - there's even a 6x3.5 I'd like to try for lifting heavier loads, potentially, hehe
@@STRIKINGFPV the Roma f6 has typical 5" motors. If you're looking for thrust, you need 2807 1500kv motors and high pitch 6" props.
excellent job
Thank you very much!
Seriously, you’re based in Phuket?? Totally cool. I look forward to watching your tests of these loop designs.
Yes I am! Lived here for 21 years or so.
Increased lift in forward flight is called "translation lift" in helicopters. It's understood to come from escaping the downdraft of the rotor and flying in "clean air".
Yes yes, I've learned about this as well, just that it appears to be more pronounced with the V2 toroidal design, as opposed to regular props, which I found interesting. Probably something to do with the upright loop edges becoming more aerodynamically relevant during forward motion, but hard to know without doing a fluid simulation I think,
The blade should transition to past vertical fully out and the vertical helix will taper outward as in a vertical helical curve. Also close to center you need a twist based on radius. The best first mod on the MIT HELIX should be oval. Second mod will be over vertical pointing in an elliptical outward curve in the furthest radial extension. Basically the tip extension should function as a conical turbine extension and be helical prop more central. The issue is drag vs thrust on the radius.
I have been swimming helically for years using my hands. The issue will be seamless transition from helical thrust wing to conical blameless turbine as you progress outward and how much you do this.
In swimming you can feel this transition in your hands as you feel the pull on your arms change with hand motions traveling in a figure 8 pattern.
Really cool, appreciate the work you've put into this.
My pleasure!
love this video. love your work. thank you! keep it going!!! 🙏
I think you should remove the flat face on the bottom. For SLA it’s not necessary and will make a more efficient propeller
True, guess I'm still trying to support my FDM brothers who've managed to get airborne. And obviously myself, eventually 😅.
Will consider doing an SLA/SLS only design at some point
Hey man these iterations are really good! Excellent explanation too! I'm an engineering student from the UK and I'm trying to replicate or rather design my own toroidal prop design. Im currently inspired by the sharrow NX toroidal propeller and im attempting to recreate it! so far to no success... I tried doing a similar method to yours with the rails but with coils to include the 3D geometrics but I think I'm going the completely wrong direction aha. Don't suppose you could do a tutorial in attempting to recreate it? also, another challenge might be to attempt to recreate the CX-1 toroidal prop it looks simpler than the NX version but its harder than it looks when I'm trying recreate it! Thanks so much, dude! Again great work!
Actually I've been planning to do a tutorial for a while now, but just wasn't really happy with my file layout, seemed really messy so it would've been a massive headache for both me and you to try replicating, haha. In my latest video though, I do announce the release of the STEP files and my plans to finally do a tutorial on my design method - it's certainly not the best way of doing it, but it works alright and I'm sure more inspired and talented engineers can improve upon its main concepts.
super interesting. just heard of this a few days ago
I wonder how the design would perform in counter rotational arrangements..hmm .I have a couple of y4s laying about I may have to test..
If CZcams supported GIF comments, I'd totally put up an Arnold Schwarzenegger "Do it, do it now!" GIF
My 2c and sorry for the "backseat designing" but I feel the wing should start almost vertical at the hub and gradually transition to a shallower angle of attack... finishing totally horizontal at the periphery, and then working back up towards a steeper angle after the transition. This is definitely NOT what the MIT design does, but it is quite close to the Sharrow boat prop design. Conceptually.
The outer edges of the props only create a bit of lift in purely upward relative motion, but creates quite a bit when in a diagonal relative motion
Consider moving the toroids away from the center, and using a bar to connect to them
That could well be why @willitmod observed the increased lift during forward flight. I could maybe reduce the size of the tips, which might be able to resolve that effect, but maybe it could be a feature advantageous for forward cruising.
Your newest ones made work fantastic. I used them on my nazgul 5 4s.
I don't have it on video but I did a roll in my lab with the very first set, line of sight. Great to see so much interest. The tribade first flew on a 5in quad as a proof of concept and I experienced similar struggles and successes. Thomas Sebastian lead the design with an intern and I worked on getting them in the air. SLA did better on the stand but I found them to be too brittle for real world temps and conditions.
Hang on, so you're part of the MIT team that worked on this? I think I have many questions, but not sure where to start. Also, I hope you guys don't mind us messing around with designs and doing this whole mass prototyping thing 😅.
Did you have much input on the design or do you have much insight or recommended shapes or design methodology, by any chance?
@@STRIKINGFPV I am indeed a small part of the MIT team. To be clear I am not the designer but I am in the video and was operating some of the drones in my lab. I took part in small geometry changes to help make it printable and different materials to improve strength. I also did drone tuning/piloting, and thrust stand testing. I am actually excited to see what comes out of the FPV/open source community. I am not sure how much I can say and will try and get back to you after bringing it up to the stake holders. The tri-props were V-1 concept and designed by hand. We left a lot of headroom for geometry optimization. The V2 Bi-props were designed parametrically for the sponsor. We have alot of concepts left to explore. www.ll.mit.edu/about/facilities/autonomous-systems-development-facility
@@roboticsjoe3181 Small part but crucial part of the team, don't sell yourself short 😅. That's very cool work you do, and a cool facility as well. Had I grown up on that side of the world maybe I'd be doing something similar.
I understand that you're limited in what you can share, but thank you very much anyway for that little bit of insight. Crossed fingers that your stakeholders might let you share more, but I understand if they prefer not to.
If you'd like to get in contact, you can grab my email from my channel on the about page (I think). If the powers that be would allow, would be cool to get on a call or something 😅.
Checked tri-50 version. It is still too heavy. Cura says 7g per prop, and regular 5" props are 4g per prop. But bi blade version is much lighter, it's good and ua printing now. As for tpu, what i found with original 3.5" version: after some RPM they just collide and swing around motor :) for me they worked for hovering, but a bit more throttle and they turn into a mess :)
Okay, so tri-blade needs even more of a diet 😅, but looking forward to the bi-blade test 😁
What sort of TPU did you try? The hardest I have is A95 and I feel like that would not be enough for such a thin print. I've been thinking of getting some D58 for other projects and maybe that would be good enough for these as well.
@@Qwarzz considering tpu is by far the strongest material. I think any prop of tpu will unbreakable. But too thin will not work, just twist
@@Maxbl4 Yep. But not all TPU are equal. Some will be more flexible than others.
We can 3D print a mold and inject that with resin. I have done this with two part silicone to make custom gaskets. I can't figure out how many parts you are going to need but it should be possible. For another project I plan to make a mold that was a tiny bit over sized out of polysmooth. Poly smoothe is smoothed with isopropyl alcohol. It looks like blown glass when you are done. By sanding the mating edged I would remove the rounding at the seams caused by the smoothing process. You could just sand and paint it to get a smooth mold. Bolts right through the center of the loops will hold it very well. You could also reinforce it with fiber glass. I have some Kevlar roving that could be put inside the molds. Normally yon want the element of a composite that are strong under tensile load on the outside but when it is this thin I don't know how to do that.
Awesome work, I don't have a Fpv drone (yet), so im planing to scale it up to 7 inch and test it on my flying wing
That sounds cool, would love to see it on a plane as well. At that size I'm concerned about the blade thickness, since others have commented that the larger sizes seem to flimsy - I'm hoping my next generation will fix that with thicker profiles at the hub.
@@STRIKINGFPV Ill keep you updated, will probably fly on the weekend but for now it seems to hold up well enough and produce sufficient thrust.
@@STRIKINGFPV I actually tried the V2 bi toroidal propeller and it worked great, when close it sounds like a loud hairdryer but it actually is much quieter and lower pitch when I fly farther away, thrust is also great but it takes a while to accelerate and decelerate
Got a new sub here. Awesome job on the prop designs. I think the tpu idea is great on the tri-loop version. On the issue of deformity, you could try to add a ring on the circumference of the propeller. Basically connecting each vertical section of the loops. In theory, that would keep them from being able to stretch apart, and keep their overall shape. A quad loop version would also be interesting to try.
There have been a number of good suggestions regarding improving rigidity for TPU, but the more I think about how it deforms under heavy torque the more I think we'll be losing out to increased weight, which then deforms more due to torque, etc, becomes a vicious circle.
I think the solution is more along the lines of a more rigid material, that's still flexible. @willitmod actually found that Silk PLA is really bendy and had some great new flight footage with that. Then apparently people of the resin world can mix regular and flexible resin to tune the flex which is so cool.
I think that this loop blades will come to their full potential when used for vertical wind turbines. Just remember to put two Frisbees on both the top and the bottom.
Completed printing PLA versions of the tri blade props. Weighted them and they are within .01 gram of each other. Havnen't tried flying them as it's too windy, 30mph gusts outside. In the mean time tried printing Nylon versions but they didn't work so well. Now in the process of printing some with clear PETG and they look promising. Will try to fly tomorrow weather permitting. I guess the best place to report results is in the comments here?
That's interesting that nylon didn't work out, since nylon is one of those unicorn-y materials that one would expect to do well, assuming you've got your print settings dialed-in and the filament adequately dried. It's one of the reasons why early on I settled with PETG, since it was a little less finicky (but still finicky) than nylon but also quite strong. May I ask more specifically how the nylon prints failed?
For results, feel free to comment here, or like upload your own video and tag me, since I'd love to see flight tests and it's just weird and fun seeing my props working on other people's drones 😅.
@@STRIKINGFPV regarding printing with nylon the main issue was that the trailing edges of the prop were warped and uneven. The prop also seemed to have too much flex to work but that is just a observation at this point. I did dry my nylon for about 8 hours at 55c. I'm going to try again later once my PETG prints are completed. Have been doing additional drying of the nylon in preparation for that just in case that is the problem. I will let you know if I have any success with that material. Also thinking of printing with some lightweight PLA that I have laying around. It's supposed to be as strong as normal PLA. The surface isn't as glossy/smooth as normal PLA but don't think that will matter much since the layer lines are present in the prints anyway.
As this design is right now, it is not moldable with the 2-part mold that is typically used to manufacture props. I think it can be modified in a few areas.
From what I've read about injection moulding and having seen in person actual moulds of various items, I do believe that it is more or less impossible, certain for the tri-loop design. The bi-loop may have potential, if done in a split process, perhaps, but the more the shape is refined the more complex it would be to manufacture I think.
This could well be part of the challenge, in fact, now that I think of it, maybe the next step for the team is to develop a practical way to mass-produce props of this design (and probably patent said method, which is also fair enough).
Aero engineer here, I was wondering how it would react if you were to design the prop to have the blade rotate to a horizontal non cambered aerofoil at the furthest point. Rather than having it go vertial. As im just thinking there could be some weird aero effects caused by the portion of the blade thats tranistioning between main lift generating secion of the arc to the verital edge section of the arc.
Totally
Totally agreed! I just made the same remark without seeing yours 😉
I was wondering about this and I also made a mention of this in my latest video, but my general concern with that idea is that I feel like it then results in creating a blade tip, which is sort of what we're trying to remove? But either way, all ideas are fair, I'm not sure I'll try it out myself, but hopefully more people will get a chance to do so as more people start to design their own. Hopefully I can help with that when I release a design tutorial.
7:36 the outside still looks quite steep, maybe you could try and tilt the outer profile forward to reduce that...
also congrats to 50% more subs ;)
That's the big question mark, how much further out do I want to "delay" the "uprightening". And can I butcher the language regarding toroidal prop design more 😅.
Have to think about that for the next iteration, absolutely.
I don't have any ABS around to give that a shot but maybe someone else does. Print a pair from ABS then Vapor smooth them to get a smooth shape to test with. I'd love to try to print and fly a 5" prop.
I do dig that idea, I completely forgot about acetone vapour baths - feel slightly ashamed because back in the day I used to print in ABS for motorcycle parts, but the most exotic thing I print with nowadays is PETG-Carbon.
I think you need to make the very outside profile have an angle so its a lot sharper and decrease the drag. atm the vertical profile will increase drag at a minimum when you are turning
I've considered angling it inwards and outwards, but it always negates one of the joining edges in some way such that the best thing to do for now is to just shorten it much much more which improves the blade angle further out too. Check out my latest post and design where I've done this. Still WIP and not all the sizes are uploaded, but getting there.
The design is very interesting, I'm trying to use this design for computer cooling. The standard fans have an inner diameter of 110 mm / 4.33 inches and an outer diameter / housing of 120mm. It would be great if these fans could also be used for PC water cooling and more power could be produced at a lower volume. I'm trying to adapt the designs at Thingiverse and make a fan like this. Many Thanks for your inspiration and also The Video.
Building it is one thing. But _optimizing_ it could be a major challenge unless you have access to desktop computer with seriously high-end computing power (maybe!) or better yet, getting time to access a real supercomputer. Reason: the mathematics in propeller blade design is extremely complex, to say the least.
Have you ever designed wings before? There is a lot of science that goes into the shape and thicness of the foil, I would think it would take some incredible math to just understand the most efficient straight propeller designs, in order to meet the needs of what it is designed for. But what you are dealing with here is not a foil on one axis, with the center being that which will be fastest, but also it will slow down as it generates the thrust, then because od the blade curl under, there is going to be pressure from the outside loop, and how that air is moved over the blade will mean everything, but then you have to consider the backside pressure which directly affects that flow speed and direction on the interior. I like what you are doing here, but you could look at this like a fancy paddleboat vs the MIT thing which is super advanced research and mat5h going into calculating the speed and density of the fluid of a screw on a modern day submarine. Fluid dynamics is fascinating, and perhaps you can gather the relevant data, but I would say the person that won that award has probably been hard at work on that for quite a while.
The patent and implications of this technology are huge! Hopefully you and your community will be able to derive something producable. I would guess it would need to be some kind of casting process though. Or maybe liquid printing? Not sure. They do have one of these for boats and they cnc an alloy. OFC it is a much more aggressive leaning loop, for more thrust at lower speeds.
In future iterations I think I'll probably end up researching more traditional blade/wing designs and try using them as loft profiles, potentially.
The big headache for me now is getting good enough at designing in Fusion 360 such that we can simplify the design process so that more people can try their own versions and see what really sticks.
Would love to pick the brains of the MIT guys somewhat, maybe see if they can offer guidance, maybe even share their process in the spirit of open source (despite the patent 😅).
@@STRIKINGFPV OK well, I subbed to hang along. I notice there is a playlist for MIT fluid mechanics, and as you should know air is just a less dense fluid, so plenty to research out there! Not so much about a 3-d application of it in a propulsion sense. Fascinating stuff!
It is a 2 dimensional thrust vector over 5 Positions of thrust counter rotating 360° from 10 angular momentums = 24 Dimensions for 12 Attitudes Drags 2/5√360√10=24
Five blades, not three
This is super interesting. What if instead of taking the leading and trailing edges vertical, they become horizontal and the upper edge on the front becomes the lower edge on the trailing half of the loop? Does that make sense? That would mimic the shape of props now that reduce drag on the tips by flattening out.
Yes, so a more horizontal profile - I've considered this and I do also outline in my latest video why I probably won't be trying that soon, since the horizontal edge profile may end up creating a wing-tip, which sort-of negates the whole concept of eliminating the wing tip by looping it. I'm also uncertain of the geometry that would be generated between the leading blade's trailing edge and the trailing blade's leading edge (now that's a confusing sentence, haha), I feel like it results in just a single blade with a hole in the middle.
You might be able to compare different designs simply on the basis of hover - carrying known weights. Until people compare measurements, not just personal impressions and videos of things without scale, I do not see you ever getting the global prototyping and collaborative design world you think will help. Share models, share measurements on prototypes, share detailed recordings of precisely reproducible tests, share the algorithms, share the flight data and control signals, inertial measurements, and flow measurements. I think you can use that laser air ionization to inject tracers into the flow at precise times and locations. The laser focus can be programmed to match the needs and scale of the test.
Tethered hover tests (known weights) and local power, will allow testing for hours or days, not limited by batteries. Fewer parts on board - focus on the lift and small small control changes. You do not have to make big movements to test, You just need finer and finer measurements. A whole test rig might fit over a table top.
Yes it matters have fast you print. If you check laser cutting, plasma cutting, 3D thermal printing, and many other 3D fabrication methods -- they ALL are art, not science, yet. That means small changes in the way something is "printed" make a lot of difference to surface, strength, internal acoustic resonances and strains. Flow is something that goes down to atomic scale. You can modulate flows to make them easier to measure and easier to modify and control. If you tether and do not have to worry about weight, then you can use powerful computers and sensors first - and iteratively converge to high value and interesting combinations (designs).
You are doing good things. I suggest you add $Thanks so people can support and encourage you. If you have specific needs tell people. Be sure to write more, because the words are what the search engines find, not what is in the video (now, maybe one day...)
Richard Collins, The Internet Foundation
That's a lot to absorb, but you are correct. I think at this early stage though part of the main challenge is not so much the fine design changes but more the print quality, as this type of development is heavily reliant on consistent and good manufacturing, which is still difficult and basically impossible for FDM, so part of this is to get people excited in being able to print their own and test them out to begin with.
The people with access to higher quality equipment and finer resources are the ones who will really take this and run with it, in fact I've had some university students mention to me as well that they'd love to work on the concept more, asking for the design files which I've now released along with my latest V3 tri-loop and V2 bi-loop designs. And in the future I will also release a tutorial on creating the design in CAD.
At that point, with more people able to modify the design themselves, those people would be able to do more intricate and meaningful testing, and I have hopes that they will share their findings with all of us.
Or maybe this will all fizzle out when the hype dies down 😅. It's the internet, after all, and we have limited attention spans sometimes. Plus I don't do this for a living, haha.
Nice job, but it might just be me, but I think there is a principle error in the design where the loop blade the front and rear part are in the same plane, i would make the rear part below the front. This way you can easier get a more constant shallow going to 0 AoA over the tip, instead of going vertical at the tip which is just pure drag.
This could get very interesting in sets of counter rotation blades.
Tuning for noise cancelling
perhaps? Iterations combining triloop and biloop. Very promising for ductless/ propguardless cinewhoop use.
Heyo, maybe even quad-loop 🤣
The triloop copper set was my fave. The biloop really tamed the whole of DJI FPV
Adding forward airspeed should increase lift because the airspeed over the advancing blades will increase.
Yes, I think I didn't emphasize that Johnny's surprise was by how much more transitional lift the toroidals seemed to get vs standard props. I now think that the V2 design's very tall vertical section had something to do with it. I had a feeling that my V3 tri-loop design's would behave more normally, and I believe I've achieved that, having seen the V3s tested by @MoppelMat and flying quite comparably to a regular 5" tri-blade.
@@STRIKINGFPV Could it simply be that there's more blade surface area than on a traditional prop?
I watched that video as well, and I wonder if the same effect could explain why he was losing so much lift in turns, because the resulting airspeed over the prop (especially the props on the inside of the turn) is lower, given the lower free-stream airspeed. What I'm getting at is that that prop may be taking more advantage of the free-stream airspeed. Perhaps a prop that is more optimized for hovering would make it more like traditional props in that regard.
@@sthomas6369 Very possibly yeah, but if that were the case you might also expect 5- 6- 8-blade props to exhibit similar behaviour compared to a tri-blade, but I haven't yet seen anecdotes of that type. Would be interesting to test actually.
czcams.com/video/wAXWpmX8gcM/video.html tested 5" bi blades.
1. Flight quality is totally like normal props. Good grip, propwash all stuff. Balance is acceptable, was flying on BF 4.4 default pids and filters
2. Low efficiency probably 50-70% efficiency of good regular props
3. Noise is pretty high, probably higher than regular tri blade, but the pitch is much lower. Maybe this will it less intrusive in the distance
4. Did not explode under around 70% throttle on a 6s 5" quad :)
Good stuff!
Your analysis re drag.. A "tricky" part of designing props for multicopters, they are "optimised" for the flight regime of hover- ie, we wold like to see max efficiency for zero blade advance ratio - minimum drag in the rotational plane is a task to achieve. (thinned loop tips are likely to produce lower drag).
Then one can redesign for a range of advance ratios - to test for different flight styles from camera ship through to freestyle or race (high advance ratio)..
The intersecting loops are doing some complex intersection drag type of thing - that has downsides. A nonintersecting "bi-loop" (or tri) could also be made in VP fairly trivially, potentially suited to full size aviation applications - or is a really aggressive scimitar tip a better choice?
I wonder about the non-intersecting tri-loop as well, actually. I dig the intersecting one because of its overall more rounded shape, so it's definitely more suited to indoor drones with proximity to people and things, but I figure the current bi-loop design is more efficient, so I imagine a similar looking non-intersecting tri-loop would actually perform better, but be a bit more slicey.
I should look into simulation actually, I would be fascinated to see what weird fluid dynamics of actually occurring at the edge of the loop, behind the leading blade of the loops and also the intersection points. Must be really weird looking.
I’ve been trying to model these myself but I think I have a lot to learn in fusion lol
It's pretty steep - honestly, even the way I modelled mine is kinda' janky, still not satisfied with how I've done it, but it works. Eventually I'd like to make a tutorial on designing props like these, but I'd like to get a method which works well, otherwise the tutorial might raise more questions than it answers 😂
Hi, one comment : why did you put the external shape vertical? You should try to put it vertical, it would reduce the drag at the external part of the propeller. And seen from the front of the propeller, the back part of the loop would be higher than the front part of the loop, so they might disturb each other less (not sure of that as the flow should be more or less horizontal...)
Doesn't the biblade technically have 4 blades just they are close together
I was also wondering about this sightly philosophical question 😅. This is why I quite like the term bi-loop and tri-loop, which maybe should become the standard way to reference parts of a toroidal prop.
Your doing such great work.
What has MIT actually patented? My light reading on the topic has discovered that this is not a new technology or design. The previous limitation was materials and manufacturing complexity. These drone up cost, so more cost-effective designs took the lead.
I tackle this in my latest video actually, but I believe one of the novel ideas as mentioned to me by another commenter, is the intersection of the blades in the tri-loop design, which apparently hasn't been written-about before. But I would agree with you in that these props will up the cost due to their difficult manufacturing, and their benefit currently doesn't really outweigh the cost increase I think.
For the tpu you should account for the flex so that under load they stay at correct attack angel