>The domes are almost impossible to print on a FDM printer What if i told you... that you can flip the model upside down? :)

Considering the obtuse and complicated nature of this - you should be pretty proud to get it working first try

"Honey? The neighbor is making UFO's in the backyard again!"

Coanda effect and ground effect, most ambitious crossover i've ever seen

I spent a long time testing propulsion in a partial vacuum chamber to see what might work best at Mars. As it turns out, ordinary propellers beat every other option hands down. My advice when converting electricity into thrust... Use a standard rotor profile, size the tip-to-tip length just below a length that would send the tips supersonic, and you will get the most thrust possible.

Call me a traditionalist, but I prefer my drones and the tomatoes in separate formation. Great video as always. Well done!

This is an awesome example of experimental engineering. Sure, it didn't result in a faster, more efficient, or better drone, but it WAS an interesting exploration of using the coanda effect. Experimentation and sharing what you learn benefits us all. Cheers, thanks, and keep thinking outside of the box and trying new things! Thumbs-up!

This is how DiVinci got started. Theory, trail, error, improvement. Keep at it!

I love the fact that nowhere in this entire experiment is the question "why?" even considered!

Tom : Propellers are stupid for this Also Tom: Propellers are better for this.

The air screw is the most efficient way for thrust.

This was an excellent demonstration of "controlled folly". Thank you.

Always good for fun video involving flying machines

Just curious why you didn't print the dome as a bowl, with the open side up.

A bold attempt to prove a complicated and involved theory. This is real science and we will be watching to see how it evolves.

Very interesting and well-done. Bravo and Thank You !🌞

Vacuum form thos bowls! Lighweight, fun DIy project and many more applications!

Hi Tom, Nice Project! This system works on a skin boundary layer effect. The current impeller design system is flinging air away from the surface boundary. You need to print a funnel housing for the impeller design to increase at surface air flow velocity. What you will find is that the stronger skin effect creates a flow entrainment effect that causes ambient air to flow along with it. ... So even though the funnel housing adds weight it causes the impeller flow to be much stronger. A second thing that you can and should do is to create small stand off wings in the skin effect flow channel. (They act like stators in a jet engine.) What this does is it redirects the air into a more downward flow direction. With your current design the flow is traveling in a spiral over the domes. You want the flow to be as close to vertical as possible. ... The other thing that can be done is to use a second impeller on the bottom. This sucks air in from the center and pushes it out toward the edges. This dramatically improves flow drag performance. The outer flow and bottom flow meet at the edge and eliminate turbulence... All that said these types of lift systems are just not as effective as props. They are used for lift craft that come into contact with physical objects. .... Try those changes and hit me back. You should be at about 65-70% power efficiency of a direct prop system but you should break ground effect. ... Cheers!

Absolutely interesting, inspiring and I believe it has a real application.

Love the fact that you spelled it the right way. Great video 👍🏻

I think the way you explained the Coanda effect with the curved plastic instead of a spoon like everyone else does is unique and more engaging. Great video by the way!

Huge problem with this design... propeller airflow cools the fan motors, impellers don't cool the motors at all.

Thanks for sharing your experiments, they are inspiring

beautifully explained in the beginning clarifying my concept of lift and also coanda effect.

The domes create the Coanda effect, but also create a huge drag and turbulence under them. Maybe a complete "drop" shape under the impellers could improve efficiency. The "drops" could be helium filled balloons. And impellers big, low rpm (low KV motors)

Tom Stanton The Last Air Bender

proof of concept. Good job.

Well, the solution to reduce weight is simply to use the 3D printed dome as the form, then use a lighter, thinner material molded to it. Vaccuum forming would be ideal, but you could also likely use something liquid applied or heat shrink.

Before even clicking I could hear Tom going "co-anDER effect" in my head

This video has taught me more about fluid dynamics than my mechanical engineering degree so far

Curious how the size/shape of the ‘bowls’ affects efficiency.

This is significantly more interesting than I was expecting

Suggestion, Shorten the skirt/lower part of dome, it does not add to lift but only adds weight

TBH, when I first read the title I read "Canada drone"

I am aware that this video is 3 years old, but I don't understand why you didn't just use 4 lightweight salad bowls. They're smooth, symmetrical, and cheap.

Thank you great effort. Appreciated. Yeah the ground effect was clearly there

In 70' I had book about building hovercrafts and hovercraft models. If memory serves coanda effect hovercraft was given entire chapter.

Your videos are a ton of fun for this old engineer to watch.

As a Romanian, I am very proud of you for using the "ă" corectly. :D

Thats simply remarkable 👏 bravo

As a Romanian, I appreciate that you spelled correctly, Coandă. Cheers!

Tom you are missing the "Coanda Duct", that constrains flow and increases the velocity. This may (or may not) make this device work better. OR, one large coanda body scales better.

Dude, well done on what you achieved here !

Outstanding work

Simple impellers by design are way less efficient than propellors. Even though the propellor version flew better I like the impeller version more since it’s a radical different way of creating lift.

The open bottoms of the domes is allowing pressure differentiation to almost equalize, plus they act like sails. I love your work, your initiative is to be commended.

This explains the design of flying saucers. This answers so many questions.

Well done. Very interesting!

Flip the bowls so the dome is on the bottom and you won't have an overhang problem when printing. Also you can do vase mode and make them super light.

>They're (motors) going to get quite warm What if I told you... that propellers are meant to both cool the motors and lift the drone? :)

I have always respected the work of Mr. Hiller, you are on the right path.

Henri Coandă would be really proud of you. Nice work!

Excellent video mate... I love the fact that you built it and tested it... well done!

Have you considered extending the domes into an aero spike? Laminar flow is beast.

I was reading an interview with Coandă, in the original romanian language, he was talking about building models when he was younger, but with persistence and playfulness he was able to achieve so much more.

i think you can increase efficiency by inverting the domes, make them rounded cones, like funnels, and make the each impeller blow horizontally on the wider lip of the funnel into it's center. i'll be less odd looking for sure, but i believe it'll work better, and still use(at least partially) the coanda effect.

This was an interesting phenomenon to learn. It seems like the coanda effect is more of a condition that impedes aerodynamic performance than a property which enhances or lends utility to. Your video was enlightening and entertaining, thanks for educating!

You should try a Magnus effect drone!

Good video Tom. Your initial thrust tests basically predicted the outcome. I imagine the Coanda effect loses efficiency since there must be an outward thrust component, and not all of the thrust is directed downwards as it the case with a propeller. You might want to revisit this with redesigning the bowls into a similar shape as the Dyson fan, which is based on the same principle. Cheers from Canada.

Fun channel you have here, Tom.

amazing....I love experiments like this. It is very enjoyable to me. To see how others minds do creativity that helps others learn and expand their own.

I wonder if pressure could be leaking between the pieces, perhaps sealing the tomatoes off could improve efficiency. Also, missed opportunity not printing the toppers in green.

I think the impellers need stator vanes surrounding it. Just the impellers will spiral the air around the domes losing efficiency. Stator vanes direct it downwards and reduce turbulence

2 piece dome. brilliant!

I'd love to see a test of just the impellers without the domes. I'd expect there to be some lift just because of the low pressure directly above the impeller.

Hmm. The domes also prevent the motors from getting a cooling airflow... is that an issue?

damn this is amazing - i had never heard of this

Good design for a drone that would be landing on water. Reminds me of the subnatica drones.

I learnt so much and also had a blast watching the video. Great job.

Good demonstration. I like how you jumped right into it at the beginning.

Yeah it's nice seeing this read about this design for proposed ufo

Well done be proud and keep researching and discovering.

FOr added efficiency I'd suggest a small skirt along the top half of the impeller (since the impeller draws air from the top, and out the sides) you could essentially put a small skirt around the top of the impeller, so the upper part of the blue sahdwich extends just a couple of centimeters outears more than the bottom half, and (this is really important), to make sure none of the air flows back up because of the high pressure, the top extending part of the sandwich has to have a small, subtle downward curvature, just to push more of the air downward

Love the amount of time you put in just for the what if factor. So what if it didn't work 100 percent...you won't die wondering. Good job.🤣😂😁😀😎

This drone doesn't sound like a mosquito well done. It sounds like an army of gardeners with leafblowers at 7am on a sunday.

This is Engineering strait from the heart. Amazing

Hey Tom, awesome project! I agree with you about having some turbulent flow going under the dome because you have a radius and a rounded lip at the bottom so you end up with ground effect until the velocity of air can shear away. This design is good for a hovercraft. You need to have the dome wall stop at 90 degrees or slightly more (with respect to the ground) and leave a sharp edge to have a more laminar airflow that shears straight off the dome. Also some fins may help direct the air. Think of a diffuser on a race car. At the moment you have a rounded edge like some juice bottles where you have the juice run down the bottle onto your counter top if you don't pour fast enough. Also vacuum formed polycarbonate would probably work well for the dome. I'm sure it would be lighter.👍

This could be turned into a marine drone with the big red domes working as floating platforms.Would love to see it

I don't understand why anyone would believe this could ever be more efficient than a stream of air from a propeller, directed straight down and unimpeded. No extra turbuence. No extra weight. No spillover.

Our new video about the physics behind this effect (sorry, in Russian:) kzfaq.info/get/bejne/qstlrcyLyNS5j6s.html

You should try shrouding the impellers. In my experience any time you have an impeller for any application, it’s shrouded.

You are getting the COANDA effect, but the hollow bottom sucks air up again I guess, and disturbs the Coanda capabilities. So Make enclosed upside down teardrop shapes. They will also work as legs giving higher ground clearance. I guess it will work better. Also try a single motor too 🤔

Great work and a sense of humor in the 3D printing example in Simplify3D))) I'm glad that you practically found out for yourself why, for example, the AVRO disk project only flew above the ground. In fact, the Coanda effect is minimal (basically not at all) and everything is provided by the so-called "ground effect".

Hi Tom. I’m guessing that the impellers are losing a lot of pressure from most of the air escaping outwards instead of following the domes. Maybe you could try some curved ducts around them to direct more of the air at the curved surface. I also have a feeling that vertical ridges on the surface of the domes would pull air more efficiently as it might reduce cross-buffeting. Would be great to see a follow-up video. 👍

Make the domes out of a helium filled bag. Airship lift with added drone power.

The impeller that broke was probably producing more air flow, thus pressure and broke. Re-print that impeller with thicker walls for the additional force, should help.

toll!! sehr gut !!! wircklich fantastik!! gefällt mir!!

Everything looks awesome in slow motion

and you can sand it too to be smoother or make some geometric shapes to increase the air flow.

MAKE AN EKRANOPLAN!!! Basically ground effect to the max

Looks great to start with. My advise is to use a relatively heavier horizontal disk (Gyro) on the top placed at the center for sole purpose of maintaining stability, this will drain power though, but will certainly help stabilize the vehicle in the air.

To make the domes lighter: 3D-print a thin frame and attach foil to it. It just gets pulled (when an impellor is used) and should still be able to withstand the forces.

I like these sort of videos on obscure propulsion/lift methods, even if they aren't totally practical. It would be neat to see something based on a tesla turbine, or perhaps a tesla-valved pulsejet.

Awesome project and great job! I think you’re on to something and I believe you could get it to work. I have a few ideas, as I see many others have ideas too. 1: Majority of the lift would come from the top surface. The impeller may be removing a large section of that vertical pressure difference. You can still use an impeller, just switch it to the axial type that pulls in air from the outer diameter and pushes it down the middle. Mount it a little higher, like your traditional prop setup, and you’re golden 👍🏼 Also, this type of impeller will suck in more air. 2: Ridges on the surface of the bowl may not be a bad thing, rather near the outer edges. You’ll have to research this for the full explanation but inducing turbulent flow around the area where the laminar flow starts to separate from the surface actually helps keep the flow against the surface slightly longer, which really helps at low speeds. Examples are gulf ball dimples and vortex generated on the front edge of airplane wings. Now, ridges from printing may not be most effective, but maybe you could add tiny vortex generators or dimples wherever the flow breaks away at LOW throttle. 3: Close proximity of the domes may be effecting each other, let alone the impellers directing air towards each other. Also, horizontal movement, or winds, will effect the flow on the domes which is your lift. Not sure if this is a solution, but maybe add walls to separate four sections 🤔 maybe each dome could be inside cylindrical tubes. I’m thinking like the Parrot drones that have foam wall attachments. 4: THE DOMES COULD ALSO SPIN! This is more of a fun experiment bc I don’t really know if there would be any benefit besides acting like 4 gyroscopes lol

Videos about failures are way more interesting than successes

Wunderbar! Eine richtige Schnapsidee.

I like how i live in the country where the Discoverer of this effect was born! He made romania a flying country of happiness!

Could you use an aerospike like 'nozzle' on the bottom to increase trust and efficency, potentialy outwaying the weight penalty?

That thrust being produced is applying direct drag in a direction opposing the thrust and therefore straight to Weight vs Lift. Your attempt with the original impellers seemed the proper path ad maybe with maybe a shroud to channel all the thrust over the bowls. But then again the propeller is the most efficient mover of air as the Wright Brothers efficiency was over 90%. Great Project and enjoyed the knowledge gain...

Have you thought of making the dome shapes into lightweight helium balloons? You could mount the motors above the domes from arched outriggers from the body of the drone.