Can an X8 do it better?
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- čas přidán 1. 07. 2024
- www.FPVCycle.com
Table of Contents:
00:00 - Intro
01:04 - Insane concert video
03:02 - Why X8 7"
05:05 - 4S flight video - X8 7"
07:02 - Detailed review START
07:06 - Betaflight vs Emuflight
07:45 - Frame
08:16 - 6S flight video - X8 7"
10:32 - Kinda special arm spars
11:12 - Resonance issues
13:53 - Coaxial Kv variation
16:44 - Motor numbers - INTERESTING!!
20:12 - Battery considerations
Y6 video: • Can a Y6 do anything b...
Motors: fpvcycle.com/collections/motors
Frames: bit.ly/3FgiIeN
Sonicare 5" frame: bit.ly/3IEz2Z4
The flight controller: bit.ly/3HjXmPu
ND filter: bit.ly/3vsVcJN
This video is fantastically awesome!
UNTOLD festival movie: • UNTOLD Festival 2021 |...
Stay tuned to www.FPVCycle.com. We've been working extremely hard on a bunch of new things.
▼Join the FB group for more discussion: FPVCycle - Kabab FPV
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$1/mo from 1/4 of my subscribers will make me quit my job. Thank you
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www.FPVCycle.com
Table of Contents:
00:00 - Intro
01:04 - Insane concert video
03:02 - Why X8 7"
05:05 - 4S flight video - X8 7"
07:02 - Detailed review START
07:06 - Betaflight vs Emuflight
07:45 - Frame
08:16 - 6S flight video - X8 7"
10:32 - Kinda special arm spars
11:12 - Resonance issues
13:53 - Coaxial Kv variation
16:44 - Motor numbers - INTERESTING!!
20:12 - Battery considerations
Y6 video: czcams.com/video/i_RJJDsy_qs/video.html&t=
Motors: fpvcycle.com/collections/motors
Frames: bit.ly/3FgiIeN
Sonicare 5" frame: bit.ly/3IEz2Z4
The flight controller: bit.ly/3HjXmPu
ND filter: bit.ly/3vsVcJN
This video is fantastically awesome!
UNTOLD festival movie: czcams.com/video/v9Ic8u_V3Mo/video.html
Stay tuned to www.FPVCycle.com. We've been working extremely hard on a bunch of new things.
▼Join the FB group for more discussion: FPVCycle - Kabab FPV
facebook.com/groups/379155946182689/
▼ Tips?
Patreon: bit.ly/2oGLP9b
$1/mo from 1/4 of my subscribers will make me quit my job. Thank you
-PayPal: www.paypal.me/kababfpv
-Bitcoin: 1E4XZXoD4rS6MYWVWuenY7Kw2M1YgyNpoQ
-Nano: xrb_1188ek5bd7tb9kw67asnp9o65byuoaxbtpxuznx1ribf75x78awywmakj55f
-ETH: 0xD067F93811f2eC31CB1928901002dfdf9A492EF5
-LTC: La2KWYAjp4VT2Lq2M76pbjzXWvRyjpfCtG
Did you try just extend the 2nd motor straight out the arm ?
Impressed by the concert video where fpv quad being involved in production. Can't imagine Fly over a thousand ppl, fireworks, stage, that was freaking awesome ... insane skill 🔥
Always a good day when you upload! Interesting stuff
Thanks for the new video! Hope you'll have more free time to do whatever you want to do!
Yessss! We were missing you and your exploring so much. Welcome back 💪
Happy to have you back
happy to see you came back
Good to see you back Bob!! Missed your in depth videos
Nice build I like the push for innovation that's the whole idea of having a hobby aside from just flying good to see your making videos again looking forward to future videos again
Hey Bob I just wanna thank you for your hard work. I came back to hobby after couple years of break. A lot has changed since then... But I remember the times you were posting videos quite regularly. I hadn't known how much value they had until I came back to see that this channel is no logner 'as' alive. Thank you for the knowleadge you have passed in those films. Cheers mate :)
I'm working on an update to this video right now actually. I have more time now, coming back.
I hear ya on being so busy I have a brand-new success set up with all of your parts on and it’s been built for two months now with being snowy in Michigan and busy at work I just haven’t been able to fly like I would want to but the days are getting longer and warmer. I’m glad to see some content back up as I always like seeing your views on our flying toys
Incredibly cool Bob. That concert footage was out of this world as well.
Long time since you have posted. Glad to see you posting again
Nice to have you back Bob!
Always a treat to see a new Kabab video posted! 👍🙏
More, more, more! Love your videos!!!
Very interesting. Had to stop what I was doing to watch the video. Looking forward on the next one.
I have missed your videos great to see one again
Was very pleasantly surprised to see this pop up in my feed 😁
Glad to know you doin aight & Sall good man everyone gets busy; These fancy GPVCycle motors ain't free shitttttttt we all been busy grinding hahahahaha
You really know how to do testing! Thanks for sharing the knowledge with us!!!
Great to see some new 7 inch development after your first venture into the 7 unch frame I super excited with this. Really hope you have this 7inch available I've missed every one since the orginal that was robbed from me. Good to see you posting 👌
I have quite an interesting concept I'm going to test in a couple months for 7"
Yeees finally a discussion video:) Missed it
More Kababble. :D Yes, Bob does tend to rattle on here and there, but it's usually entertaining. While I don't always agree with his conclusions, I can't argue with his determination to experiment and improve. He certainly has refined his designs to a high degree. This has resulted in my favorite quad in my fleet being my ToothFairy which is solid as a rock and nimble too.
Keep it up Bob, I'm still watching and waiting to see what's next. :)
Great seeing you ripping at our old spot. Man, that thing is fast 👊🏻
It sounds really good... excellent attention to detail here, thank you for your work. Very interesting and engaging, I am interested to follow this project and see how it turns out. Personally, I think you are onto something here.
This is very interesting! Thanks for the video it is helpful as I scope out adding 7" options to my working fleet.
Very impressed with this whole video. The frame is beautiful, the knowledge is insane and ability to make such a smooth and fast flight is astonishing. Well done sir.. You may have tempted me to make this 5" im looking to buid to become a 7" lol
Was wondering where you've been, hope you're doing ok, very interesting video as always :)
Love the innovation! Thanks Kabab!
Instagram photo has come to life! Really excited to see where this goes. I'll end up needing something like this for work, so you've already got yourself a buyer lol
Excellent video thanks
Fantastic flying, Bob! 😃
Really interesting quads! And... Flying things, I guess. 😬
Anyway, stay safe there with your family! 🖖😊
I miss our talks :) Hmmm all very interesting ... I have to say though, recently started flying 8" stuff with the ultra high pitch props that are available in that segment and don't think I'll ever really go back to 7" until something similar is available perhaps. 8" on 2810 or bigger is just so fantastic, fun, fast, and still can be nimble. If you get a simple stout bottom mount frame that's light you can really mount a huge variety of packs and you end up with impressive agility and if you want just something that can fly forever by comparison to 5/7" stuff while maintaining a stupendous pace.
Glad you keep experimenting with this. Very good information.
I am surprised how much difference having offset kv top and bottom make.
Gotta try it.
FE has its limits, true that!
It is NO surprise that differential motors helped.
Years ago I did some experiments in coaxial props where did differential prop pitches and diameters. Since top or lead prop accelerates laminar flow to trail prop.
Also the tip vorticies are a factor. My goal was to cancel noise (resonance) and optimize CFM to amp draw. Two get a two speed , high / low switch I halves the voltage. Tests were done with 12V computer fans on a super wicking evaporative cooling unit, which we used in our gyrocopters to fly in Arizona summer heat. Hope this gives you food for thought? Loved this content and your passion R&D. GREAT WORK!
That's a good try but yeah wasn't going to work. Getting computer fans to stop making noise is extremely difficult.
I was just wondering about you yesterday and here you are..
Concert video was EPIC!
powerful flight 👏👏
I will visit often ~!!
Can’t tell you how much I appreciate your real world testing. Have to agree on BF defaults, thankfully the new presets tab is incredibly useful and I actually like 4.3. Having said that I find it easier to run Emuflight on some quads, so I do. Easier is better. I think some people choose to ignore that tuning software is more than its PID’s, there is more going on under the hood.
Wow, insane video bro : )
Good info!!! Thanks.
He timed it with the streamers and fireworks so perfectly
If there’s only one thing I consistently do ever since I started following you it’s floss. I recently had extensive dental work done and now all the gaps between my teeth are so large flossing five times a day between anything I eat is ridiculously necessary... you officially have a convert!
🎉
Keep up the videos man badass man....
woh00 finally a video great !
Very cool stuff. Got emu downloaded and flashed yesterday. Can’t wait to give it a go. Was also wondering if the sonicare performs ok on 2306? I have a few sets laying around, and don’t have the dough to buy the imperials, and the frame at this time.
Yeah 2306 is completely fine. I always advocate to use what you have first.
Great work Bob! The trials of tribulation is the hardest part I could only guess and hours of time put into your research and development is amazingly exciting for all to learn and apply by. I still have the floss v1 frame but need a new bottom plate due to it splitting by an arm strut section. Does your company still carry these frame parts? I ended up using a set of 6” arms on the 5” frame. Helps with stability and movability. Actually it’s my fastest rig I own at the moment. Gods speed buddy. Thank you for all that you do for us and yourself in this hobby. ;) 🤓
Sick flights and freaking fast. I would be scared to death of someone surprising me and walking in my flight path. Nail biter.
Middle of the day in the height of traffic. I knew everyone there and nobody is coming. Was a safe area. I fly here often.
Almost a year ago, I had the same thought:
"Wouldn't it be a lot more efficient and faster responding when the bottom motors of an X8 would be higher kV?"
So glad that an experienced and dedicated man like you had the same idea and is actually testing it. And even better, that our thoughts seemed to be right.
For the x mounting problem, you could cut a bit of the mounting end of the arm horizontally an have a similar shaped 2 or 3mm plate. Countersunk screws on both motors, then screw the parts together with 3 screws and pressnuts.
Maybe not the easiest mount to work with, but would be pretty compact and same shape as X4 layout
The next craft is close and very exciting
awesome info. thanks for your ongoing research. vertical fov of your flying footage seems quite low. is that a gopro 10? new hypersmooth cropping hard?
It's a hero 8 with the minimum amount of anything reelsteady does. I like the lens rectification reelsteady does and I also can't edit the footage without preprocessing with something. Two birds with one stone.
Can confirm over crowds and around the stage at a concert is 100% one of the most intense gigs. I've done flights with Rezz and Nghtmre.
This is awesome! I’m working on a GoPro specific x8 as well! I think my approach is a bit different than yours but this is giving me ideas…. Your 31mm motor is my go to for 7”!!! Thank you!!!
For a light X8 to drag a GoPro around, I can soundly say the setup I have in this video is significantly better than any 3106.5 quad setup I've ever flown. Super intesting already
@@Kabab what’s the endurance/flight time you’re aiming for?
@@javagadro I'm hoping for 5min of fast cruise with a 1900mah 6s
7:30 I am late, but I will say, those shakes are from the higher than needed I gains, or low PD gains. BF stock tune is for the light racing rig, you need to drag the sliders a bit for other types of the rigs, I had the same issue on 7 inch, and on 3inch cinewhoop too, thats a common thing for their stock tune.
freakin awesome!!! watching with itnerest and peasure. what kv on 2306 can you advice for 4s x 8 7 inch?
Not sure right now.....I wouldn't recommend 4S for 7" in general however. It's just not enough voltage and the batteries will struggle to supply the amperage to manage a craft of that size unless it's a middle or low performance craft. If you're just hovering around, it's completely fine.
You're a wizard, my god.
I have exactly the same sort of random bumping on bf and my 7" with 2306 Motors. I already ordere new motors because I thought they haven't enough volume to spin the props... You definitely encouraged me to try emuflight!!
What is your opinion on motor size on normal 5"?
I am still running some 2204 on one of my 5" and Beginn to wonder how much is just hype on running crazy motor sizes like 2505 on 5".
Also it's great to see content from you, sad that it's gotten so rare lately :(
For 5", I haven't used another motor that begins to compare to the fpvcycle 25mm imperial. Especially the new version we've got in manufacturing. It's a 2506.2 in true 1870kv. Sure smaller motors work fine on 5" but this motor is the intersection where it doesn't really make sense to use a heavier or bigger motor. Also, our 25mm motor is lighter than many 2306 motors so it doesn't really make sense to go with something smaller.
Anyway, I think 2306-2506.2 is the correct range for 5".
As for the bump/tick problem, it's not the motor. It's the resonance feedback in the system. Apply damping grease to the motor base between the base and carbon if you have some and run default emuflight.
The top added piece thats added the additional oscillation you mentioned, is that due to the motors making the same power with same torsion but more forward because of its flat strength? Causing the props to not spin flat like the bottoms would?
Hard to describe but my best guess is that because the motors are somewhat around the same RPM a lot of the time, the rotations match up and in this case, because of the motor offset, the resulting oscillations are oblique and unpredictable. This is why the FC is having so much trouble. Oblique oscillations are the absolute worst to deal with.
The coaxial group with different kv is my personal logical reasoning too. with this coaxial engine offset, even more than vibration problems, it is offset gyroscopic torque problems that create problems
Great analysis of your coaxial setup's handling! Instead of a Kv differential between the upper and lower sets of motors, have you tried running steeper pitched props on the lower set with similar Kv ratings? APC tends to be heavier but they've got a good selection of 5" and 7" bi-blade pitch options. 7x4 + 7x5 or 6 combos could be worth a try to help accelerate the initial thrust from the upper set instead of hitting rpm limits.
I tried different props but it's really hard to find a matching pair of props that would work well together. APC props tend to be rather inefficient for the task at hand. They're really good for speed but not so much for control and efficiency. Other props also are deceiving in their function. It's more difficult to find a matching pair rather than just upping the Kv. It's even more difficult to find a matching pair of twins and if you do find a matching set, you can't fine tune it. That being said, this may be the direction that we need to go if my theories about how the FC functions are incorrect.
Something I've noticed about the 7035 Gemfan biblades is they come really out of balance. Maybe I just got a bad batch, but on my light 7" build with 1870kv imperial motors on 4s, swapping those out for the triblade version reduced vibrations a ton. Might be worth looking into a different 7" biblade if they still have balance issues so you don't need as much frame mass to counter the vibrations.
It's not specifically that blade, it's twin blades in general. When you have a tri-blade, you just have a better counterbalance on the blade so even if it is out of balance, it's not noticed. Twin blades will almost always be somewhat out of balance and because we are so sensitive to vibrations in our video feed, we see everything. Thankfully, in this situation, having so many blades seems to improve things quite a bit and I'm seeing very little issues in that department
Great video!! I to am trying to make a living chasing cars on track. Finding a quad that can keep up while also getting above 3 min of flight time has proven difficult. I'm excited to see you findings! Currently flying a 9" with 2816 motors and a 7" with 2810 1500 kV motors. Really interested in the x8 setup!
This is exactly the situation I'm trying to resolve and I feel is the most obvious use for our FPV crafts.
@@Kabab Ya I feel the same way, I can't wait to see what you come up with!!
my quad from 2019 just went up in flames. I want to replace the elctronics. what is the best 4 in 1 ESCs and FC for 6s that you recomend?
With the Glide and Terraplane... Ive never had to tune on BF and 4.3 just makes setup easier. Ive never really used anything else though.
Did you ever get a chance to test same kV on top and bottom as a control to compare to? With 8-9" coaxial X8 I found with 900kV on top and 1115kV on bottom performance didn't change much and I actually lost a bit of efficiency. The "freeing" feeling you described I was able to achieve by running triblades on top and biblades on bottom. Maybe with much larger heavier builds these things don't always scale like expected...
interesting. This thing definitely feels much more 'free' than any other coaxial setup I've flown but it's entirely possible it's a result of the favorable disk loading proportions too. I'll know with the next test. Triblades on top and twins on bottom or vice versa is really a total unknown. twins can spin faster because of less drag so maybe they were picking up in the RPM vs the thrust being produced from the top as opposed to the forward advancement ratio on top vs bottom?....so hard to tell....and yes, as I've learned first hand and explain at the end, just because what I'm doing here might work doesn't mean it'll work on a full weight cinelifter. We don't totally know what's going on still.
Hi, i know you tested different kinds of motors for your toothpick builds. In your opinion which motor will work better for a 1s 2.5 inches toothpick between 1102 18000kv and 1202.5 11500kv? ( If you have other options let me know) thank you 👍
1202.5 will absolutely 100% without exception perform better with respect to control. The 1102 might be slightly faster overall but won't be as enjoyable to fly because of the limited control.
How am I supposed to remember to floss if you go this long between videos?
Thanks for all the interesting content.
And don't worry, I've flossing even though you haven't been reminding me lately.
interesting about using different motors kv on the top and bottom.
Here we goooo
Hey Bob I’m binge listening to your channel while I’m at work welding, I’m planning on buying some motors as a treat to myself lol. But have you ever tried using the master slider only in betaflight? I just set mine to 1.3 and it makes a huge difference. Anyway no criticism from here. I don’t know enough to criticize lol just a thought
I actually attempt to use their simplified tuning across at least one full pack before giving up and moving to emu
@@Kabab I’m sure you know more than I do.. Either way these a long form educational Videos you post are a lifesaver during a long Night at work I personally appreciate them
@@lordhenrix1510 I may or may not know more but that doesn't really matter. My goal is to do as little work as possible in order to get things flying at 90% of Max capability. I cannot stress how little I strive to do in order to get the best performance per unit of time spent. This is one matter that betaflight seems to not care at all about. They expect you to spend hours tuning each thing you build to get something that actually works let alone flies good
Whats your fav setup for sub250g for lightweight cams like the caddx peanuts (other than 5")?
That's the tooth fairy 2 with your choice of motors. The 21mm is the lightest for 5" but I'd recommend the 5mm arms on the tooth fairy 2 with the 23mm tall motors
Hey Bob. Did you consider removing the bell from the lower motors and stripping the threads and screwing from inside the bottom motor to the top motor? This will be a solution that would make a lighter less vibration prone craft. The bell securing screw being missing, shouldn't cause any issues.
That's sort of a lot of work. I'm not trying to make a one off craft. Also can't quite put the bell back on once the two motors are mounted to the frame.
Maybe not a bad idea, should still work, even without screwing back the bell on the bottom motor, since the magnets are more than strong enough to hold it in place while not flying and while flying, the lift of the props is pushing the bell up against the stator...🤔
Hey great video! Will you be coming to UNTOLD this year? :)
My gosh it's my dream to go to that festival. 2023 if I'm lucky I'll make it there.
@@Kabab it was really great! Too bad you missed it but maybe next year 😊
Yeah I've noticed the same thing with BF over the last few years.. I've spent hours trying to get it tuned to no avail.. EF is definitely better but I still find KISS just feels / fly's better than both for me. That said BF 4.3 + the new BLH32 firmware definitely seems better at least on the few quad's I've tried it on!
Try the emax nanohawk x its basically a babytooth but bnf
Very interesting how despite having so many motors and props spinning it is getting similar flight times with the same batteries! I can recommend the CNHL 6S 70C lipo, I've had good luck with that one personally if you are looking for a 2200mah 6s. Also the Hobbyking Rhino 2200mah 6S 50C is not bad either.
CNHL packs are fine but tend to be larger and overweight for their performance. They're cheap but the loss in value is greater than the reduced price imo. GNB packs under 2000mah are very good. I'm going to try and get the 1900mah high C GNB 6S pack to work for this craft.
Are we gonna get a vid about all the new motors + setup recommendations?:)
Once I figure it all out. Yeah
What is the key to your amazing motion-blur? Is it because you absulutly rip at proximity to the ground? Or is it more the right settings and ND filter? My guess is that's an ND32 you're using?
The ND filter we have in the store. I developed it to look as close to invisable as possible on a budget. It's as clear as much more expensive filters and it's an nd16. I run the cam on auto and I think give it a max or min shutter speed or something. One obvious setting when you look at the menus.
Just looked. I set it to max iso 1600, min 100 and shutter speed of 1/60. That way the blur is consistent and the can is only shifting iso to compensate
@@Kabab thanks a bunch!
does hanging the top motor off along the arm change anything? and not to the side?
i'll have to give emuflight another go
electronic circuits deliver the most power, when load resistance matches internal resistance of the supply
that is usable power, the one put to work over the load
so for finding the right motor kv for the battery you are using, you could look at the resistance through the motors, that the specific kv produces
but i'm not so sure how to extend that to multiple motors and to which throttle setting to tune that to
is that something new whooping in the garden? felt small
All these questions are correct but the industry is generally a fair bit past these questions. Figuring out how to deal with the motor EMF and managing resonance is more of a problem today than anything else. The EMF issue isn't as big of a deal.
I’m glad you reminded me to floss! 😆 I have crooked wisdom teeth that I need to get removed. Is it bad that I just left them in and I’m 27 years old now?
21:45 "GNB kinda seems to drop a cell on packs that are about larger than 2000 milliamps, for some reason their cells above 2000 milliamps are problematic..."
Oh... last week I received two 9000mAh GNB packs, a 3S & 4S which I'll be wiring in series to get 7S to re-cell my ebike battery. I hope I don't have any problems with them!
U should try the ovonic 1000mah 6s super lightweight I run them on everything from 4" to 10" been flying them for about 2 years now
I've got lots of those. I've had them for over 3ys and they're still going strong. Really good packs. Minimal degradation after a WHOLE LOTTA charge cycles. Those and my Pulse packs.
Man, It's great to see a video from you! @13:00 in, have you considered centering the coaxial offset, rather than having one motor centered and one motor offset? (and rather than having them both centered, like a traditional coaxial.) Newtons 3rd law can be a bitch! Just curious if the motors are offset an equal amount off the arm, both top and bottom, maybe it would even out that torsional flex/harmonic? I don't know, just a thought. I hope all is well Bob!
Yeah I talk about that in the resonance section too. In hindsight, my idea to offset is just stupid mechanically but it does make sense aerodynamically. I just didn't realize which was more important until I made the mistake
I've made a 5 inch x8 and it flies very good, I have a short test flight video of it.it has apex 2207 1850kv, radix2 and 2 hobbywing 60A esc set to 48k. I had to edit this to say I avg about 7 min on a 1600mah,session5. auw is close to 700gms and flies like on rails. I built it to keep up with wings for more than 10 seconds. The frame is a custom cut by me with staggared mounts inline with arms,arms top motors can have up to 6.5 inch and bottom could go up to 5.5inch. Props in on top ,out on bottom.
The staggered mount worked fine for me too until I got to 7". Then it became an issue. Figures that 7" would be a problem. Everything on a 7" is a PITA.
i think mounting motors on top of each other introduces unpredictable turbulances because the props will be aligned at certain times and orthogonal at other times . depending on alignment the air pressure might be oscilating very fast. not sure about how strong that effect is but i guess it exists. different rpm of each motor might smooth it a bit would be an interesting test on a static mount.
Coaxial setups are just inefficient in general because of how they function. By having motors that just spin faster on the bottom, it seems to improve things quite a bit
holy moly
Lol, Kabab comes of of a 3 month hiatus with a mixed kV coaxial hexa-quad. Do you think if we give him six months he’ll be working on nitro rocket quads?
For your coaxial 2nd gear issue, have you tried different sized/pitched props? I was on the apc website and read this in their faq question about prop combos for coaxial motor setups:
APC recommends that a larger diameter be used for the leading (upper) propeller and a higher pitch be used for the trailing (lower) propeller. For example: an 11×4.5MR for the leading blade and the 10×5.5MRP for the trailing blade. This will provide more balanced loading on the motors and make the multi-copter more efficient.
Its clearly for larger craft, but I wonder if it could help with this particular issue. Instead of staggering your upper and lower motors using those little extension tabs going to the sides, you could just extend in line with the arms and create room for larger props up top at the same time
There are a couple of research papers out regarding small UAV and drone coaxial design, and they all come to this conclusion. Hope @KababFPV sees this and tries to implement
@@dgood9591 haha I hope he does to, however I'm under the impression that he's pretty far along with his next video on it. I've seen him talking a bit I'm the cinelifters Facebook page about this exact topic, I'm sure it'll be pretty interesting regardless
I've tried different sized, different pitched and different blade count props. They all have varying degrees of effect but the RPM change between top/bottom had more of an effect overall than prop swaps. I am however limited by prop choice. There just aren't that many props in these sizes.
How do folding or hinged props change coaxial performance? I would imagine it would help but I've never seen anyone try.
hinges or any moving joints in general are no good for vibrations. On a low powered craft it's not a big deal but if you're going for really tight control and high performance, you can't expect a loose joint to work out.
Damn we miss you 🥲
It would be interesting to monitor and log the current draw of each motor in different coaxial configurations and KVs. This would tell you where load is going and you could sudo-load balance via motor KV to create a more efficient machine.
If I only had time
@@Kabab I hear ya. I’ve thought about things like this a lot. But this is just a petty hobby to me that I barely even indulge in anymore lol. I’d rather build a custom fuel injection system for my go cart 😂
What you think about x8 with 7'' top and 5'' bottom? Using shorter arms for bottom motors
Or maybe the opposite
5" on top makes more sense to me....for a wide variety of reasons....but you still have the same issue where you have the 5" blowing right onto the 7" prop which will never be able to process all that thrust and then add to it....which is why you could consider the 5" under but then you have the same issue again....the 5" drivetrain needs to be super aggressive....which is then inefficient.......it's all s conundrum that requires real world testing.
My main rational to stay with 7" is because I'm aiming for higher cruising speed and better disk loading properties. Going down in prop size wouldn't help those goals.
If you say you run stock betaflight and emu always flies better, do you at least run rpm filter #s in bf and move the filter sliders all the way to the right?
I do try BF with and without RPMf
Love the x8 biprop idea.
wouldn't higher pitch on bottom make sense?
or tri on bottom and bi on top? oh you did that on the Y..
toss in some floppy props...
I tried that with the last build. That would work too but it's more difficult to find suitable props that match. It's easier to use the same prop all around and different kv. I can also control the kv more finely than the prop. There isn't a wide variety of 7" props out there that are worh trying on any build either.
Folding props are actually best but still nobody makes a good folding prop. The folding deal never caught on because of the lack of good options. The DAL Fold 7 is the best folding prop IMO but it's also a triblade. Running triblades on the setup I've got would make it a lot less efficient unfortunately.
Hey Kabab, I'm building a 7" X8. (still waiting for the last parts) Do you think the lower motors can handle being the landing gear? Thanks :-)
Yesh it's fine to touch down on the bottom motors. Just don't smack the ground and disarm quickly just before you're gonna touch
@@Kabab Great Thanks! Parts arrived and currently I'm building. So excited!!!
Thanks a lot!!! :-)))))))))
I wonder what impact editing the mixer matrix so that the motors on the bottom have a slightly higher multiplier would have. Not quite the same thing as using a higher kv but that seems to be what you're accomplishing.
That would work the same except that you would hit the limits of the bottom motor sooner than the top if they are the same KV. The easiest way is to just run higher KV on the bottom because then you can just run the same prop all around
@@Kabab Ah of course, makes sense. Though since you can set the number precisely that might be the cheap way to test multiple different proportions of top:bottom motor kv.
@@TheBellman yes but unfortunately it's not linear. I did some tests and figured a little differential is gonna help but it can never be as if there was no coaxial setup. So just enough needed to get to the point of the diminishing returns
when will these new frames be available?
just with 4 motors.
This is still early stage testing. Hopefully the next iteration works as expected. If so, then I'll get a test frame batch. The same frame will work as a quad too.
Lately every quad I've built has been about 25% larger motor volume than "recommended" for the AUW.
What are you using at the end of the video, os that some sort of cinewhoop??
Yeah it was the tooth fairy 2 with the cinewhoop arms. Haven't done that video yet. Will do soon
Hey Kababfpv I really really lobe your contents and your parts , what I didn't understand was why Justin is not just stepping up to 12S on a 7 inch like me, I am a fulltime Pilot flying 90 percent Motorsports drift , dragrace,,stockcar and rally thats m, shots, I had the same like Justin, less speed by using to much amps, now I fly my 7inch as a 12S with 2x1380mah 6S lipos I get about 12min of flightime and I can push it way over the 220kmh mark
The issue is the complexity of charging and flying. Right now he runs just one battery. 12S will require two 6S packs and takes more time between flights. It's just himself flying. He doesn't have an assistant to swap quads. Also, he doesn't even fly 6S. He flies 5S because you get more flight time by having a larger capacity pack than a higher voltage one so he's much more limited still. 12S is definitely the way to go however. Just not convenient because of the battery/charger issue.
I agree, you should get rid of the motor offset, it looks terrible, use some other design that works good already, also yes they make that Gemfan 7035 bi-blade you can find them everywhere.
Good to see a video from you, Bob!🦷 I've been having Fpv discussion withdrawal! We love to listen to you talk about multirotor flight!