Watch Chris's release of his new motor! kzfaq.info/get/bejne/jbVhd5Oc19qWZHk.html

Two legends, one video

I'm glad Chris Rosser is using his engineering super powers for good and not evil. Awesome, amazing work!!

At the risk of sounding like a terribly scratched record… we are so fortunate to have Chris. Science is my life, so his systematic approach to optimization is just such a welcome, needed, fresh breath of air in this hobby. I love Kabab and I’m genuinely grateful for his contributions as well. To each their own, but this is the level of engineering expertise that I have always wanted to see. Thanks for helping showcase and share the knowledge, JB!

Dude, I love this guy so much. It is incredible to get engineering insight into how our gear works in a way that manufacturers don't provide. Thanks for going in depth!

Stack mounting; resonance cuts that we use in saw blades. It’s a good idea, with a lot of science behind it. I like it 👍🏻👍🏻

Sick. Bardwell, Rosser & Ian are downright the best trio for improving almost everything about our hobby. Keep it going.

Ok i m gonna play devils advocate. How major companies developing motors for years, with engineering teams and equipment worth hundreds of thousands of dollars, never heard of Nelder Mead optimization (which is a very simple Matlab optimization algorythm I might add). Chris is a legend, but I am sceptical on this one. I cross my fingers and hope it's the legendary, groundbreaking, physics bending motor he claims it is though :)

I'd love to see him also apply this process to a motor for sub250 builds

Two kg per motor is nuts, so exciting to have Chris applying his engineering skills!

That's a fascinating topic for me. I mean to simulate stuff and then try out in practice. Because then, if you find discrepancies... You make discoveries! Which can make our models and theories even better. 😃 A perfect example of it is cosmology. There's always a huge simulation running at some super computer, while we have things like the JWST making observations that we can compare to. 😃 Thanks a bunch for the interview, Joshua! And thanks for your work, Chris!!! Stay safe there with your families! 🖖😊

WOW Chris and JB! You guys are so great for our hobby and I love what both of you guys do for all of us! I'm grabbing a couple sets of those motors boys! Cheers!

The way Chris explains the technology, it makes perfect sense, AND he has the numbers to back it. I already see a few posts where people already have them…

Chris is just such an amazing contribution to this hobby in total. Love flying those AOS frames... let's see what the motor will feel like!

Chris's motor is going to do very well! He gives alot of time testing for us. People will support him!

Ive heard some people in the hobby speak ill of Chris rosser, one even actually referred to him as a charlatan. I must say though, after watching his motor testing video, i ordered the rcinpower WASP majors (because they had excellent test results)... and they REALLY are the best motors i have used yet. People can say what they want, but my own real life experience backs up Chris rossers testing. I am very grateful for the work that he has done for FPV, almost as much as JB. I trust both of their opinions over everyone else.

I would say the influence of the ESC is just as important as the motors. The choice of components and the matching of mosfets plays a major roll in what happens to the motors. Fake components are also a major problem. Drones being as good as they are in general is something to be grateful for. Nice to see Chris being so enthusiastic on motors I'm sure he'll improve things.

can’t wait for these motors to ship

the Flight controler cutouts is pretty sweet idea. I could see where the gap would allow it to float. and could control the contact points.

That frame idea is amazing

Chis Rosser's innovative work is absolutely incredible

What a way to look at it Chris yes your motors may make other motors better thank you in advance

Two brilliant minds, leading the quadcopter world to a better place. Man, this is exciting!

for chris, vibration isolation: think about mounting gyro/stack not to a bottom or a top plate. mount it in the middle by using for example the standoffs -sidewise. so its "floating" but stiff connected to the sides. the metal standoffs wont bend. OR: use the stackscrews as standoffs aswell. make them screwd to the bottom AND top plate additionally. it wont be likely that this area will bend if its connected in a "cube" bottom and top. its isolated for itself what do you think?

Chris: Hyper Parameter Optimization for AI models… Josh: mmm hmmm 🧐

The flight controller mount is a neat ass idea.

This new motor sounds awesome! I usually stay away from expensive motors, but I'll have to get these at some point! I hope they spend enough time in stock to grab them in the future. It would be awesome if Chris made a motor like this for a 3.5"! I bet they'll be a lot of prop deflection, I wonder if we'll need a new line of props in the future to handle both these motors and the general trend of heavier more powerful quads. Carbon fiber props would be interesting, but definitely too dangerous for freestyle. Great interview JB, this is my favorite type of fpv video! I really like the deep discussions about fpv products and fpv theory, as well as the science behind it all! I've watched all of your interviews with Ryan Harrell at least twice.

I think Gal Kremer can independently test those motors. He has a Tyto Robotics thrust stand

This is why I love using this guy's frames. So easy to get jello free video even with the different prop options, including dual blade.

Get this guy a Nobel prize.

Can you go on a motor making spree? How about the most efficient 7inch or 10inch motors

Ok, that vibration dampening idea is great - brilliant. One of those things that once you've seen it it's "obvious."

Awesome. I love how Chris dives deep and truly innovates. That spreadsheet though... showing 6 decimal places / 10 significant digits for thrust measurements?

Logic and rationality are limited to what we know sometimes assume. Breakthroughs happen unexpectedly often enough thru accident. Therefore restrictions for preconceived efficiency can be counter productive. Many proto types are test for unexpected out of the box or reaffirm your expectations. Great discussion !

Joshua Bardwell for president!❤

These are totally going to be in my next build!

Excellent Interview I hope it works out well for Chris he seems like a really nice man, thankyou Joshua👍👍👍

I'd love to see more low KV motors for use in robots, if there's a way to get just a few Nm of torque out of a 200g bldc at 250W for £50 we'd have jumping robots, amazing CNC machines and emobility for everyone!

This all sounds great on paper. More efficient means less heat which is great. Now lets hope the bell design can handle a beating.

Very interesting approach to the vibration situation. More recently I've been testing a change in the orientation of the main deck and how the arms attach. I'm finding some nice consistent improvements. Combining this with Rossers cut outs as well as bracing for the areas around the carbon bridges to the stack may lead to further improvement. I'd love to push the limits of the motor software to inspect some of the unique motor designs I've come up with. Especially if it can deal with reluctance forces. Not just for FPV. Rosser and I historically seem to be on the same wavelength so I'm sure I can just wait and he'll come up with similar ideas on his own. Lately I've been looking into things that there are no answers to. From motor designs, gearboxes, batteries, battery management, carbon integration and manufacturing methods. There's a shocking amount of bad engineering out there across a wide variety of industries...

This sounds good! My only worry is magnetic dust.. There's a lot of that in the bandos we fly here around Denver, can really kill a motor quick when a bunch of it gets into an air gap. But hopefully the less leaky flux ring will help!

I learnt several things today!

I found a long time ago that switching to 3d printed soft mounts with a firm tpu. Worked way better than purchased silicone soft mounts. Probably for this very reason.

Basically chris is a fpv engineer we all need💀

Great talk. There's not a more solid guy in FPV.

This was a learning class. thank u both of u.....................

Guys this show was fantastic!

Legit the first time im excited to try AOS and rooting for Rosser... in the past ive had opposing experiences to his test result's including his first frame design and motor analysis. Causing me to disregard him completely. I hope I get a chance to see and experience these motors and frame designs for myself

I may not be a engineer. But I love freestyle quads and motors. I have flown a few types. I would enjoy making them scream.

I had a few years ago same idea virtually, but never tested it in production. In the video the cut around is very simple and I believe it is like very un optimized solution. I have been think to properly create mechanical resonators tuned for specific freq. by cutting the frame in very specific way.

Very interesting, FYI there's a few minutes of dead space at the end of the video (39:58 to 44:23) that you might want to chop out?

Can't wait for Joshua to test these 🤩

sounds like the fpv will be perfect with this guy products. will see

That's very interesting, especially the frame stuff - to me, anyway. I fly small quads up to 4" props. Recently, using a commercial one piece frame (2.5mm CF - carbon fibre) I have had big problems with loop stability with aggressive props, had to back off gains a damaging amount. A friend with another similar commercial frame (3.5mm CF) didn't. But, his frame was 33.5g as opposed to mine at 23.5g - a big difference in a 200g craft, 5%. On the basis that the biggest contribution to stiffness comes from mass furthest from the centre of gravity, I then made a frame (I have the CNC tools) from 2x 1mm outer skin CF, with 2.5mm core of 3D printed polycarbonate/CF. Total was actually about 4.2-4.3mm as the 1mm skins were slightly less than 1mm. Big improvement, no stability issues. Carried out some relative deflection measurements and it showed the arms (same XY plane shape) were a lot stiffer. Relatively, my original 2.5mm frame under a set load deflected 0.33mm, my friend's 3.5mm frame 0.11mm, my 4.25mm 'sandwich' frame 0.06mm. not only that, it only weighed 25.5g, less than his. So, a big stiffness to weight improvement. It seems to me therefore that stiffness to avoid coupling into the gyro is very important. In the past on smaller quads (2") I've also got measurably better gyro/accel performance by AV mounting the motors. Of course the downside of the sandwich approach is likely damage in a crash, the arms will be less strong as the 3D printed material does not contribute much to the overall strength. Depends how much one values performance against robustness. The tool I use for designing this stuff is FreeCAD, and that does have an FEM (finite element analysis) module. Therefore since one is only after relative qualitative improvement, it might well be interesting to experiment with different shapes / cutouts using that.

So interesting! I hope he applies this same core concept to smaller motors, too! I love rocking motors with a 5mm hub on my 3.5” but motor choices are so limited. T mount sucks (hats off to those of you that can consistently get the damn screws into each hole for each prop, but a single 5mm shaft is just so much easier). I’m rocking xnova, but would love more options!

The cool thing about being "just a nerd" in the drone industry is, you're always professionally surrounded by all the engineers and designers etc. that don't have any personal interest in drone flying as such... ;)

Not for nothing: They are 22.5 x 07.5 So 10% more volume but the same weight (approximate) as 2207. Bell is much lighter. So less durable? It then becomes a finite analysis on strength comparison. So that would need to be done.

I would only have liked to have a little more images to accompany the words, for those of us who are not native English speakers it would be better. But it is spectacular to see how far this can go, thanks to people like you. Thank you so much

Durability tests are next. How does it handle crashes into hard objects

Excellent approach to engineering a better motor!

He is absolutely right. If we were at the limits of motor technology, they they would all be at the same power level, amp draw, and performance. But they are not. As most of us know........ Excellent point! And pretty sure how he did it. Been on my mind for about 20 years........ i hope im right and he made it.

Im interested in seeing JB's test of the motors now ahah

Incredible interview! What wonderful knowledge and information. Appreciate it very very much. Thank you!

I'll be interested to get my hands on a set of these to try them out. Chris Rosser definitely has his stuff together and is very knowledgeable, I always fear that efficiency and durability are inversely proportional - maybe he solved this one? Can't wait to find out.

Chris is a treasure

Those cuts are pretty smart. Allows the rest of the base plate to vibrate, but not pass that into the stack, via a ridgid compliant mechanism. The same opposite of the gyro basically.

Chris is amazing.

Great interview. I would really love to hear about the entire process of filing the patent, including how he decided it was worth the costs... I was always under the impression that the costs were prohibitive.

I like the frame design for the fc stack. He essentially took wake/wave dampeners in lakes and oceans and applied it to the stack… but scienced the fuck out of it.

Great interview ~ 10~30% variability is huge.

Well lads, I been listening for the whole video about dry engineering, but 2 things I hadn't heard mentioned is that makes worlds difference is firstly the winding density in the motor, Is it wound with round wires or are they rolled square wires to fit more copper & less air gap in the conductors to give a more intense magnetic field in less volume of windings. Also I have heard nothing about the 3 phase controllers for these motors can be drastically different in the way they deal with back EMF & drive switching, Coil resonance & ringing problems. Anyway I guess that's another video hay as all I've heard is about tweaking mechanical materials & design which is very impressive but do consider the electrical side too which is a whole nother kettle of fish.

definitely gonna be checking them out

Responsiveness should measured by thrust change per second - it would allow to include propeller issues. In absolute and relative terms. For example how quickly engine spins up from 0% to 90% of thrust , and from 50 to 75.

I hope for super efficient long range motors. I'm going to get that 10 inch AOS too I am super happy with my AOS 7 UL.

I dont want to put you on the spot chris rosser: every question puts him on the spot😂❤

This is very informative

This is like a bore and stroke job on an engine.....same weight, mo power.😊

I think Chris is always more about “synthetic” numbers, while Bob is always more about real feel and performance. Would love to hear Bob’s thoughts about this “most powerful and most efficient motor”.

It would be nice to see these motors for all size ranges of quads. It would also mean you could run the smaller motors meant for a race or freestyle quad in its size category on a bigger class quad for insane efficiency builds. Ie a 1305 or 1404 on a 4 in .

I bought a set 😁 just because they sound awesome 🤯 looks like I'm building a fpv 😁 i have a mini 3 pro 😉 thinking about an 03 air unit to go with my DJI rc. I have been looking at the hobbyking orca as well. Couple months I've been seeing that around. Also saw a speedy bee frame 🤔 master 5 v2 i think. That looked interesting 😁 guess i need to go back and watch some more videos. Thanks for everything guys 😁

yoooooooooooo. Now please Mr. Rosser do the same science to all the popular quad sizes! 3.5" next!

Well done interview JB 👍👍

For a fpv drone radio, which gimbal is the throttle default like, which one is the one that most people use

So it weight as much as the 25mm imperial motor ~34g and make more power than a 28g 2207 (Five33) motor? This is really interesting, but don’t call it 2207 if it’s not a 2207. An extra 20g in a build isn’t really that much I suppose.

23:05 you can also make the ESC compensate for that delay by sending out a higher-than-necessary current so that the motor reaches the required RPM in a shorter time? If the current required to spin at 2k RPM is _x_ A, instead of sending exactly _x_ A to the motor, send _2x_ A or even more, for a short period and then ramp back down to _x_ A when it reaches the target RPM. Unless they already do that (wouldn't surprise me) in which case 🤷

Loved the video! Very informative!!

Interesting video. The method Chris has used here is very similar to the way neural networks (/AI algorithms) are trained to do whatever they do so it's not surprising that the tool he used is to wrap the MIT algo is 'borrowed' from that field. I think more and more engineering is going this way actually. Come up with a digital twin and throw millions of tweaked model variables at it.

Very interesting video, I have learned something today 🙃

Wow! Electric motor designer uses magnetic analysis tools to optimize a motor design! Extraordinary! Whatever will he do next?

Chris Rosser - Basically the Apple of FPV... "We think you're going to love it"

It'd be cool to see a top plate with these cutouts for vibration isolation for the action camera mount

But what is the tool? The finite element modeller? Is it open source? There is many .?

Must have now....

wow! what an amazing salesman!! love it love it heres my CC!!! take it lol seriously , such a good topic!

I want that ship/ motors :-) I guess I need to do special pid tune for that motors?

started listening to the video rather than watching it and my first thought was " is that tom scott ?! " haha

We need the ultimate build, no comprimises. Fastest videolink, fastest RC-link, fastest stack (h7 DShot1200 vs Kiss) these motors, least noise frame and even use dampening grease. Is it going to be revolutionary?

I could imagine a larger carbon fiber plate covering the flight controller gaps used with dampening grease could really be used as a damper system.

we're yet to reach the point of diminishing returns. that's good news for future development.

19:30 no, no we're not. Weight is crucial. 4 motors 34 g each are a total of 136 g, that is _not_ insignificant. The frame is how much? 80 g? 100 g? what's the thrust/power curve?