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FreeStyle = heavy/draggy? Not sure – FS frame needs to have space for an HD cam and be balanced well when both FPV and HD cam are mounted. Other than that, frame needs to be robust enough to crash during Evil Kneavel style manoeuvres… 🙂 Heavy? yes, but only due to HD cam. Draggy? aerodynamic profile is not a major criteria, but the lower the better still! Most importantly, COG + COT need to be centered well to allow for fast acrobatics moves…
Thanks for the insight – the draggy thing I came up with due to the fact that it seems like all the popular freestyle frames have very wide arms, but this is probably wanted for crash-ability like you said.
Wouldnt having the Lipo pointing back under the quad be more aero dynamic than having Lipo on top with camera on it? Figured depending on forward flight angle the battery might be on a 60-70* angle ,or something around there, and would be creating a snow plow bucket shape with air just complety opposing the quad?
Could be wrong though.
I know on my Merica CMM frame I stood Lipo up and mounted on the bottom like normal ,only vertically mounted it,and I felt instantly the gained speed .With it already being quite aerodynamic and having a rounded pod and stick arms weighing around 66g it must be making quite a difference if I’m noticing instantly the power increase.
That vert Lipo makes a pretty big difference tjats for sure and with frames being so liye you cant go wrong.
Been wanting a lexan rounded tube like pod made that Lipo goes in vertically and has a hole in each corner where wingnuts would hold it on to the bottom of my merica frame but this may surfice.
Might have to modify mine to accept 6s and 8s as I’m inpatient😬
It ends up being the same… theoretically. To keep the same CG/CT alignment, the motors would be inverted and I’m sure that will introduce other factors, but not enough to make a huge difference. I am just finishing up an inverted build of this frame (very easy to do using the parts in the kit) and I’ll see if I notice a difference. I’ll also have to show how it can be assembled inverted in case others want to try. Good luck with the 6S/8S modifications, I think it can be done. If you email me again in the next few days, I can at least show you how you can start the modification.
Will there be different cages for different LiPo formats? And/or different cage formats btw 4S and 6S? Maybe soft foam inserts could allow for multiple LiPo types but still hold them all in place…?
That remains to be seen. As it is, widening out the cage would make it a little too weak but I still need to revisit this. The inverted frame might be the key…
This is beautiful,thanks for the hard work!!!cannot wait to see whats to come!
Been trying to have a merica 5in pod made that is tall and holds Lipo standing up and flight stack on bottom of frame due to its great aerodynamics and strength as well as pretty lite weight .
I’m able to get around 150mph with frames not made for speed with long flat top decks so can imagine the aerodynamics of these frames will have a great increase on speed….pretty awesome man.
Interesting! How do the arms hold up in a crash? It seems like they would snap pretty easily? Very forward thinking frame design though.
The arms are stronger than you would think but they are not going to hold up like a 6mm thick arm. Generally, stronger = more rigid, but the stiffness of these arms (due to construction method) compares to a 6mm arm. It takes moderate tumbles with no problem. I also made the arms pretty easy to replace and a full set of spare arms is only $8 – hopefully that eases a little bit of the pain. I consider these more for experienced pilots that don’t do much crashing or for racers that want top acceleration. The high top speed was an unexpected byproduct. I took a look at kittyhawkfpv.com – very similar approach, also have a few notched cross arm designs too sitting around, not sure if I ever showed them in any of my project pages. The website is a disaster right now… not too worried about it right now tho, I’ll eventually get it back into shape.
That’s interesting. Never wouldve thought of bending the carbon. My only worry would be the ultracritics who want to find the perfect frame. Personally I love it though. Glad you took a look at my website!
Ultracritics and especially message boards: stay away from them and give them a deaf ear. I’ve never seen a worse place for original ideas to form, not to mention the sea of misinformation. Like Einstein said: “Every body knows that some things are impossible until someone, who doesn’t know this, makes them possible.” Learn to be your own worst critic, do your own research, and the design process will work out just fine.
I read more on your website – it is a lot of fun doing this stuff. Unfortunately, manufacturing is expensive in the US, but thats another story. I ended up going with Nick also for parts.
Yeah, completely agree. I feel like people have been made lazy their faire for conviece and simplicity — nobody likes to try new things. Nick is great. Easy to work with. Looking forward to seeing more of this frame.
Forgot to mention, I ran into the top of a pine tree today going roughly 80mph! After regaining orientation, it was still flying 🙂 I might end up putting it on youtube but my flying is no fun to watch.
Oh neat! That’s great.
Great to finally see the frames. One thing wasn’t clear to me though, the ‘specs’ mention:
“There is room between the center arm plates for a 20×20 FC or 20×20 4 in 1 ESC. windows are provided for USB/wiring access”
Does this mean it is designed for 20×20, or will old fashioned 30×30 also fit?
30×30 will fit, but not between the arm plates, but that leaves that area open for other items. A vtx and rx should fit in there together. The only reason I say “should” is that vtx’s with the old school antenna connectors might be a problem. Not home at the moment, so I can’t check… Remind me later if you need to know
Fantastic Job, glad to see it done!
I’ve been following you for more than one year and you’ve been such an inspiration so far, you really sparked my interest for quads.
However, atlthough the arms look very ingenious indeed, I am a bit surprised by the absence of any form of aerodynamic fairing like there was on your previous speed projects (XLR, VXR …), especially considering those frames were not heavier.
I’m quite curious as to why you got rid of all that nice and innovative fairing ? Is it a cost problem ? or is it due to more practical aspects (i.e. accessibility of components, vertical take-off and landing…).
If it’s only the latter surely a compromised can be reached.
Anyway, good job still and best of luck for the rest !
I knew people were expecting a fairing. I couldn’t include one due to all the reasons you listed. However, it provides a good framework for one to design and print their own fairing. Even without the fairing, it hit an average of 163.4mph on 5s (only 2.4mph slower than the streamlined 5s VXR-1 project)! Also, going fast in a straight line gets boring. So this frame gives the best of both worlds with the ability to be modified in simple ways that could EASILY break the 5S speed set by the VXR. I do have plans in the works to sell fairings but that might take a little while.
Yes, I suppose it makes sense.
My only grippe with this approach would be that the fairing inevitably increases the weight (potentially reducing the top speed) as opposed to your previous projects were the fairing itself is the working body (in a modern airplane fashion).
But yeah, I suppose this increase in weight can remain acceptable (2-3g tops) with a clever choice of material (bluefoam, mylar…) so I’m nitpicking at this point.
One last thing: On the first frame version (top of the page), is the battery located underneath the frame (as with most modern “aerodynamic-ish” miniquads, e.g Karearea Talon) or is it fitted between the vertical pylons on top of the FC ?
If it’s the latter, well done, it’s a lot safer than the traditional landing gear battery configuration !
Nitpicking is fine, it helps to clarify things: when concerning top speed only, weight has an insanely small effect on top speed. This is mostly due to the fact that the thrust to weight ratio (on just about any quad) is super high. You can see the effect in the spreadsheet I made by typing in different weight and this has been verified by former Boeing R&D and an aerodynamicist.
Yes, the battery goes above the flight controller and stands on end inside of the battery “cage” . I will have to post a picture with a battery in it. Currently I am making a new build that just needs to be wired up.
However, I will admit that there are about 3.7 dozen things on this frame that are so different that it might take some time for people to see that it works – the brave few that buy the first batch will be important, and yes, I am nervous!
Thanks for the picture, looks realy good actually !
From the way I see it, it looks like the camera mount could slide on top of the battery but maybe it’s just because I don’t have the full picture.
Also, as I suspected the arms are so thin that you have to put the wires on the side which might mess up the airflow a little. Perhaps covering the entire wired arm with tape or even better a streamlined piece (3D printed or hot wired out of foam to minimize weight) would fix that, but again, nipticking (sorry about that ;p).
I understand your nervousness but frankly, fairing or not, you came up with the BIGGEST breakthrough in frame design in YEARS, arguably since the beginning of the hobby, so I wouldn’t worry too much. The moment it wins even a few mildly important races, and it WILL in the right hands, the popularity of the frame will snowball, there’s just no other frame out there like this one (there are a few aerodynamic ones but probably not to that extent and they’re at least twice as heavy anyway).
Beside the price is actually very good as well, again a lot cheaper than other high speed frames (IMHO 40-45$ would be ideal but I suppose it wouldn’t be profitable anymore).
And you’re exagerating, the build in itself doesn’t look that different, sure the FC looks a bit cramped (but it’s not new), the camera mount is a bit unorthodox and I don’t see where the VTX antenna will be yet but it’s nothing people can’t turn they head arround.
Perhaps getting in touch with Stu from UAVfutures
(https://www.youtube.com/channel/UC3ioIOr3tH6Yz8qzr418R-g) or any similar chanel would help, I’m sure he’d have a blast reviewing your frame and it might give you a helpful headstart, who knows !
Thanks! The camera mount – that’s a perfect example of a “Hmmm, I’m not so sure about that…”. It works much better than it looks and I’ve never had the camera move at all. And while on the subject, o-rings are ridiculously resistant to cuts and wear, I was very surprised.
The wiring on the arms: there are much better ways to do this but I don’t want it to look like a specialized build. One method I like: cover some 16ga magnet wire in shrink tube and lay them on the leading and trailing edge of the arms. 2 on one side, 1 on the leading edge of the other side and cover with monokote.
About winning races: According to KababFPV, it doesn’t slow down when you let off the throttle so there might be a little learning curve when it comes to flying a frame like this. I’ll have to post the video of me trying to do quick maneuvers when I get a chance. It really is awful footage though.
I’m glad the price is decent, I tried the best I could while still keeping the fabrication in North America. I might have to hike up the shipping a little though :/ but it would only be $1-2.
I should have the frame fully wired up later today and will post pictures. The way I did it, the FC won’t be cramped at all and it is actually super easy to work on.
For the wiring on the arms, have you considered Race Wire? https://www.amazon.com/WhitenoiseFPV-Race-Wire-Set-6/dp/B078TKXDZ4
The main issue I wonder about would be if the arms bend and the race wire board doesn’t. Thoughts?
I like this idea. As far as the race wire not bending, I guess that would essentially mean that they would help strengthen the arms. It’s a win win
Ryan, I love my frame even without electronics yet. Went together so nice.
I wanted to post this here as I think this will be leaps and bounds better than the runcam offering.
For the 147 mph on a 4s did you use cobra 2207 2600kv’s or 2206?
They were the Cobra Champion 2207 2600kv motors
Be sure to try both APC 5045 BN and APC 5150 props. It’s quite a bit to explain why, but a higher pitch prop won’t always translate into higher speed. This depends on the angle of attack of the prop which is dependent on the coefficient of lift (of the prop) to the coefficient of drag (of the prop) ratio (Cl/Cd) . To make it more complicated, this ratio is dependent on the coefficient of drag of the quad. In other words, the ratio of incoming air velocity vs angular velocity of the prop needs to be at a certain value.
Interesting. It would be neat to write a program or excel sheet that could optimize a prop based on the various factors of drag from the frame. The cL/cD is dependent on the frame’s drag because of the effect the airflow moving around the frame has on the prop?
Have another question 🙂
I’m curious why something like the shendrones flaco would not be able to match the same speeds as this frame? Seems to have a very low profile and low weight (something like 60g). Is it because of the battery mounting?
Weight to thrust ratio on just about any quad is through the roof. Weight barely affects top speed – you would be shocked at how little effect it has. An increase of 20g affects top speed by less than 1mph. Acceleration is a different story.
Battery mounting and overall cross section is also a huge factor.
Many things I see wrong with aerodynamic FPV camera canopies is that they are slotted to allow camera angle adjustment. This creates a pocket and actually destroys any aerodynamic benefit – it is better to either have a hole just big enough for the camera lens at a set angle or just leave it off all together.
Lastly, CG/CT alignment is a factor. When unbalanced, more energy is spent keeping the quad stabilized.
Interesting. So the battery is the main issue. I’ll talk to Andy about the pod because he has made on with just a slot for the camera. CG alignment is very true as well.
Tell him to do a test though – most of this stuff has not been tested. For all I know, the slot might end up costing only a few mph. It might be worth it (to some) that they keep the cam adjustable. Another thing he could do is to give an exit for the air that is entering the slot. That might be the way to go.
Yeah. Very interesting. I will talk to him about it!
Hmm. End-product disappointing. Where is the complex and subtle aerodynamic form??? At this speed you lose at least 405 of energy because of the shitty air-resistance. Pffff
I’m glad you asked! I knew some would be disappointed. The aerodynamic shape will hopefully happen, but first, a good foundation has to be established. If I made a frame like the XLR, people would throw it in the trash when it takes 5 hours to repair an arm. Also, the XLR frame is too specialized for drag racing and would only appeal to a small amount of people. If somebody bought it thinking it would be a good racer, again they would throw it in the trash. I am unsure of how an aerodynamic frame would be done successfully. As of now, I think a 3D printed shell of some kind would be best since the underlying structure is there and all it needs is a cover. Again, the problem arises of specialization: trying to accommodate different ESCs and camera lens sizes – compromises cannot be made or else you get half assed aerodynamics. For example, on the XLR, I mounted my ESCs behind the motors – a very vulnerable place to put them. And for the camera, there cannot be an adjustable angle and the lens opening must be just large enough to allow for whatever lens is being used. To sum it up, it is not simple to make a production XLR type frame. As far as I see now, any attempt would only cause people frustration and the frame would end up in the trash. I am trying, but I have to proceed one step at a time – right now, a base structure that can go 263kmh average on a 5S is a good start.
What would you reccomend i get? The 5r or the lr? which one is newer/faster when using cobra 2207 2600 motors?
I just got the new frame parts (the – IR) a couple days ago so I still need to build one up and see what it can do. However, there is very little difference between the two since both frames can be built “upright” like the – 5R frame or inverted like the – IR. All that has to be done is move the cam mount to the other side of the frame. I’ll have a picture of this up tomorrow. Speedwise, I don’t think there will be any difference between the 2. More than likely, I won’t get to try it out until Monday – lots to do this weekend including making assembly instructions…
I’m looking to buy a couple of your frames…my setups will be a foxeer micro, small vtx and xsr rx, finx23 and finx30 motors inverted, with battery underneath. A 30×30 fc/esc for up to 6s and between 850mah 4s and 1050mah 6s. My question is will this be possible with battery underneath, inverted motors and a 30×30 stack? I can fabricate and make things work if you think it’s even possible. Thank you for all your hard work and sharing so openly with everyone
Easily possible. It shouldn’t be a problem. With the battery underneath, the stack will be up on top. Basically you take the “standard” vertical layout, invert the whole frame and put the cam on the stack. I’ll be FINALLY finishing the assembly instructions late tonight so you can see it a bit better.
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