Yes, the props on both boats were counter rotating! 😂 Thanks for watching my videos in 2019 folks! Looking forward to many more exciting projects in 2020. It's going to be great fun. 🙏
ProjectAir a excellent comment was explaining your longitudinal stability issue, you also have to tackle the lateral stability of the boat. A rule of thumb would take into account the radius of the foil (more or less the U or V shape that you have) and the height of the CG above the water. Then you should ensure that the radius of the foil is bigger than the distance to the water. This part is not easy to explain and a drawing would be better BUT : Imagine a small angle of the boat to the left. Rotation is around the CG. If the radius is bigger than the height of the CG, the right part of the foil will rise above water and the left will plunge, creating more lift on the left of the boat and self correcting the attitude. If the radius is less the same thing will happen BUT due to rotation, the left part of the foil will be at best under the CG, at worst, on the right part of the boat, increasing the roll! Hope it’s clear and will help you. Also, once you make it fly, add as much weight as you can so you can barely take of at full throttle. You’ll have more inertia and pleasure to drive it.
Hey! I'm 17 years old and I've learned a lot with you thank you for everything and I just wanna say hello from 2021. I'm studying electronic engineer and I wanna be an aerospace engineer. I built my first plane when I was 13 years old and please continue making more videos. Hello from Colombia!🇨🇴
Long comment, I know, but I've studied hydrofoils in-depth, so hang around. It will be absolutely worth it. Here goes: The following statement is the secret to achieving a successful hydrofoil: ***Because of the shallow V of the foil, the usable lifting area of the foil changes, depending on how much of it is in the water or not.***Consider the implications of that statement: The faster the boat goes, the more lift the foil creates. The more lift the foil creates, the more the foil rises out of the water. And the more the foil rises out of the water, the less lift it creates. Relative to the weight the foil supports, too much lift, and it rises higher, creates less lift, and sinks down. Too little lift, and it sinks lower, creates more lift, and rises up. This is a self-stabilizing system. On the other hand, the rear foil is continually submerged in the water. This means (for a constant speed), the lift developed by the rear foil depends exclusively on its angle of attack in the water. Thus, when the boat pitches up, the foil pitches up and produces more lift. When the boat pitches down, the foil pitches down and produces less lift. Now consider the hydrofoil as a whole. As the front foil creates more lift, the foil rises up in the water, causing the boat to pitch up. As the boat pitches up, the rear foil pitches up and creates more lift, causing the rear of the boat to rise up. The key is to place the CG just right such that the lift from both foils balances the weight and CG of the boat. This is how you create a stable hydrofoil: 1. Physically set the incidence of the front and rear foils to be identical, and adjust the thrust angle of the motors to minimize the downward pitching moment they create. 2. Calculate the surface area of the area of the portion of the front foil that is underwater when the front foil is 1/2 way out of the water. (I'll call this Af) 3. Calculate the surface area of the rear foil. (I'll call this Ar, and call the distance between the foils L.) 4. Find the location of the CG that puts an equal load on both foils using the following equation: Distance from rear foil to CG = L * (Af / (Af + Ar)) 5. As the boat is foiling, use very small adjustments to the angle of the rear foil to adjust the flying angle and flying height of the model, accommodate for the thrust angle of the motors, etc. Example: Area of submerged portion of the front foil: 30cm^2 (Af) Rear foil area: 15cm^2 (Ar) Distance between front and rear foils: 30cm (L) Find the distance from the rear foil to the CG (D) D = L * (Af / (Af + Ar)) D = 30 * (30 / (30 + 15)) = 30 * (30 / 45) = 30 * 2/3 D = 20cm The result is the CG should be 20cm ahead of the rear foil, and 10cm behind the front foil. This is how you create a stable hydrofoil. Notice also the implications of the above formula: If the front foil has twice the area of the rear foil, it will carry twice the weight. Secondary to that, notice that when the boat is stationary, significantly more of the front foil will be submerged than what you calculated. More area = More lift. Thus, as the boat accelerates from a standstill, the fully submerged front foil will create more lift than it needs, lifting the front of the boat out of the water first. As the boat pitches up, the rear foil is allowed a higher angle of attack, and thus it lifts the rear of the boat up. And voila! You are foilborne! It is as easy as that. But what do I know...? I'm just an engineer who wrote an entire research paper on the history and dynamics of hydrofoils.
Hey, massive thanks for this ^^. I very much appreciate the time to go through this here and provide some hydrofoiling wisdom. I'll definitely be using that formula to properly setup and tune my new hydrofoil as soon as we have some better weather. I now realise I had a few misconceptions about how you get into a state of being 'foilborne' using the elevator. I was coming at it with very much an aeronautical perspective. That's probably why I aimed to get the CG over the front foil too which I realise now was pretty wrong judging by your calculations! Looking forward to taking this to the next level. Thanks again! Cheers, - James.
I'm glad I could help you out. Of note, because this is changing the dynamics of the foils, you might find the boat is more stable with the front foil much farther forward, like 2/3 or even 3/4 of the way up the boat (depending on what looks most aesthetically pleasing, of course). It's like extending the wheelbase of a car, and as a bonus, it will make getting the correct CG placement much easier, too. I realized when I wrote the research paper that you cannot necessarily treat the hydrofoil like an underwater airplane, because both surfaces must create upward lift. It's more like those old free flight models that used a lifting tail. The CG on the models is seems impossibly far aft-behind the TE of the wing even. But because math and physics (which I won't go into here) it works. Cheers! -Dave
First, good try! I really want to see it perform on a calmer day. Second, you're fit! I'd be still sitting on the overflow. Third, we should do a challenge or something
sorry to be so off topic but does someone know of a way to get back into an instagram account..? I stupidly forgot the login password. I love any tricks you can give me!
OK, bit of advice I gave in a community post, it's worth repeating here, "don't forget the rescue boat". Oh, and another bit of advice, "don't go near water without your wellies". Keep them coming, Merry Christmas.
Just found this channel by pure accident and subscribed. Reminds me of the very much simpler and cruder experiments we tried 60 years ago when r/c was expensive and cumbersome and model aircraft were still wood and tissue and powered either by elastic or tiny, glow-plug engines. Never managed to get a hydrofoil to actually lift. Yours is brilliant. Are the air screws ‘handed’? Also, the athletics were admirable. Great fun. Thanks.
Having lived all my life at a shipyard. I think i can safely claim that a long pole with a hook at the end is the best tool for resqueing stuff out of the water. For the size/weight of these RC boats, a telescopic pole like the ones window-washers use, would probably be the best choice. They are low weight, and only about 1.2 to 1.5 meter long when folded, so easy to transport.
A more elegant solution to the "nose down" behaviour would be to have a negative angle of attack for the motor, thus compensating for the propeller being mounted so high. Have a look at the bixler 3 plane for examples.
Alpem_Warrior yep that definitely would have helped to have an adjustable ‘head’ on that mount, but alas we were in the field with just a screwdriver to attack the elevator with 😊
Just a thought, do the props on the mk.2 counter rotate? With the setup on mk.1 the motors cancel each other’s torque, if the props on the mk.2 turn the same direction i would guess that the torque could cause the instability.
It looked like you could relax the elevator some and maybe keep the front hydrofoil lower in the water. It only needs to raise the hull off the water surface. Great project!
The problem is the thrust angle. It should be angled in direction of the CG. That's why the angle you had to put on the tail was to big, and the back didn t get out of the water.
Hmm, not really sure about that. If anything I think the high moment from the elevated thrust line would force the nose down and lift the rear up - a little like how the hydroplane I built last year worked.
@@MrKipKonijn I think he means having the motors tilted down so they push though the CG and down cause the front to push down. I guess potentially having the motors tilted down would mean the front wouldn't be pushed in to the water so the elevator doesn't have to work as hard in the opposite direction. I do agree with James though.
Looks like you need a foil about twice the size as that one for that boat. Also, if you go to your local hobby shop and get some lead stick on weights and place them on the bottom center of the foils at the lowest point, that will also make it much more stable. I would also consider making a design where you have another foil just like the one on the front but placed on the rear right in front of your rudder. Keep your rudder/elevator foil on there too for stearing, this will help keep the rear of the vessel up out of the water. Good luck!
Very nice. If I had a lake close by I`d probably try to make one. Couple of points which may help. When you had the 2 motors on the carbon, they were rotating opposite, so all good, but when both facing forward, looks like you were getting torque roll. Try making one motor rotate the other direction. i.e. one clockwise, and one counter clockwise. Also, mix in some "differential thrust" on the motors, as this will work like a rudder also. good luck, looking forward to next version
you maytry to put the CG in between the two hydrofoils , such that they'd both be lifting , instead of the front one lifting , and the back one producing downforce as it looked to be like in the first prototype
It's complicated by the rotation caused by the airscrews thrust being high above the drag. How to counter that without messing up the pitch control? I can't figure out how to balance the two.
@@bikeforever2016 batteries at the back would couteract the nose down pitching moment induced by the thrust (maybe 😂) . The back wing would have to lift up more than the front one , making the whole boat a canard-style boat , relying more in the back , and maybe using the front one for pitch control .
That would have been an interesting idea to test on the MK2, I should have tried it. Was thinking at the time of keeping it more like a standard airplane configuration though.
If you're really motivated one of those Manly hydrofoil ferries is moored opposite my place on Sydney Harbour and for sale. The boat itself is cheap(-ish!) because the RR engines need work - and they are very very expensive.
Take version 1, try to move the motors further back and as low as possible. Change the thrust angle of the motors so that a line of the thrust angle goes through the boat at a point about 2/3 of the length measured from the rear. Make sure you have small increments of control for the rear foil so that as the boat rises out the water you can cut back on the angle of the rear foil. At the desired attitude of the boat hydroplaning, the front foil should still have a slightly upwards tendency to make it stay out of the water. Make sure the front hydrofoil is not too "pointy" into the water as this will cause instability as it rises out of the water. Good luck but hope to see you succeed with this one!
Some things you might consider for the Mk3. 1. Return to the center engine pylon with a "push-pull" configuration. That _seemed_ to be much more stable, although that might be an illusion because of the weather. 2. Shorten the "legs" on the foils. I doubt if you really need _THAT_ much clearance when at full speed. Unless, of course, you're trying to clear out the water weeds when you're at slow speeds! 3. Follow the design advice from Gungan Works :D He _REALLY_ seems to know what he's talking about!
Seems like some elevons and an imu on the main foil might help. Or at least some wash in on the main foil to increase roll stability. Also, perhaps decoupling the rear foil from the rudder. I tend to try to keep my inputs as independent as I can for simplicity's sake. I think using differential thrust for steering is going to be a losing battle because you've got a lot of vertical surface area cutting through the water. Remember that water is 100X the density of air.
I really like this project James. I think you might need a normal hulled tug boat with a lot of torque that can go out to save the hydrofoil to make your testing easier. Also it might be fun to add aileron as I believe I have seen that on some hydrofoils so they can control roll. P.s. Some sweet boulding on that bridge.
Are both props Turing in the same direction? Looks like when you are applying the power the boat is torque rolling. Spins the props in opposite directions so they cancel each other out..
The one thing I would say is to cut the flat section on the front foil out as it produces to much lift causing the foil to leave the water. The diagonal parts should easily be able to lift a boat of that size and will have self stabilising characteristic. I’ve done a lot of theory work with foil and have sailed hydrofoiling boat like the vampire project so you know the advice has some backing
i might have an idea to solve the turning, have you tried to install a water jet instead of props? i think thats what most hydrofoils use anyway? worth a thought.
nice adventure, huge improvements on the channel over the past 12 months great footage like the gym exercise and cliff hanger on the bridge. You first might need a real rescue boat for your boats that brings you to the places were your models stranded. and historical imperfections or so was a great quote all the best
Are you using contra-rotating motors/props ? If both motors and props are rotating the same way there maybe a torque reaction causing the rolling instability when trying to plane ?
Try going back to the contra rotating props, because maybe the two separated props are getting a different amount of air flow, and ther high mounting position mite be making it roll
it is rolling at full throttle because of p-factor of the props. your first boat was stable because it had push and pull props counteracting the p-factor. try using counter-rotating motors and props with the right motor rotating to the left and the left motor rotating to the right. Check out the P-38 design to understand what I am talking about. Although the P-38 had counter rotating props to the outside not towards the inside as I am suggesting. Concerning the wings they should be mounted further back closer to the center of the overall length of the boat and be deeper in the water. The rear wing should be larger for better control
Might the boat also have tendency to roll because the propellers are rotating in the same direction, thus creating a torque that rotates the boat? Maybe counter rotating propellors will help a bit.
Cool project! Do the motors spin the propellors in the same way? If they do, then the torque from them could be tilting the boat over. What I suggest is that you have the motors spin opposite ways and use differential thrust with them. (If you haven't already, hard to tell in the video)
James, you certainly work extra-hard on your craft! Kudos! How many RC Pilots have to do pull-ups during enjoyment of their hobby? You are one of the few brother! May I recommend a fishing pole with 25lb test and a noose loop at the end for the future subjects heading towards that overflow..? Keep up the GREAT WORK! Best regards and Happy Holidays! -Dave
Great video, keep up the good work! Nice design elements. 1 Q' You did have the rotors (model 2) counter rotating? For the Hydrofoil action ... If you have the ability to change the angle of the attack of the rear hydrofoil you will be able to rise and then keep it in the elevated position. A 3rd control channel, if you like. A 4th control channel for the front hydrofoil would be the ultimate. For operation a mix of Rear and Front hydrofoil through a lot of experimentation should be possible. Great potential for an autonomous vehicle project!
Thanks for the comment! 1) Yep they were counter rotating on the MK2. (2) Yeah I realise now I misunderstood how to control the elevator to get the model to 'plane' properly haha - although I think the new MK2 did show some evidence of the rear coming out of the water (3) A 4th channel for ailerons would be great, but also complex which is why I stuck to keeping it simple. ☺️ Cheers.
So you designed a rescue boat that needed rescuing? Which brings up a real quandary (it might even be a dilemma); which comes first; the rescue boat or the boat for rescuing prototype rescue boats?? 🤔 Also, at least it was better than the Cybertruck launch--just don't throw rocks at it. 🤣
DeadlyDiddly I was thinking about the irony of the situation at the time 😂 Thanks man, I can imagine the Cyberboat would fair significantly worse than the Cybertruck when rocks are thrown.
The MK 2 looks really cool James, I'm sure you'll mod and tweak and tune it to perfection. It looks really strong too, so I'm not convinced it wouldn't fair better than Elon's _Armor Glass_ if stoned. 🤣
@@Project-Air >>> Rescue Boat = _Canoe/Kayak?_ {On the UPSIDE, the UK does NOT have one water hazard that the place where I grew up -- Florida -- has: _Alligators_ 😊}
I think, both motors didn't spin exactly the same rpm so it pushed one side down! The first motorconcept was better! Maybe 2 times 2 motors would be better!! Happy Christmas
this boat is looking less of cybertruck and more of nighthawk, btw try using differential thrust on the motors along with the rudder for additional control
Absolutely think adding differential thrust would be very beneficial. It's one reason I decided to go for this separated motor configuration on the MK2
the mk1 seemed to work decently, however, to have a balanced fly, I would have set the rudder with less tilt after lift off (to avoid the diving issue)
Because you were making futuristic builds, do you think you can make a plane with a forward swept wing? There was a video Real Engineering made about the advantages, and I think you should try it out.
Una vez ha salido fuera del agua la proa y ya solo está navegando con el ala delantera deberías modificar lentamente la posición del elevador, sin bajar la velocidad, para conseguir que salga fuera del agua la popa también
10/10 for the climbing bit xD
That segment made the video.
😁
Yes, the props on both boats were counter rotating! 😂 Thanks for watching my videos in 2019 folks! Looking forward to many more exciting projects in 2020. It's going to be great fun. 🙏
U have to much torq going in the same direction. Reverse direction of one motor and a different direction prop and it won’t torq over so much
Make the foil on the rudder bigger witch means the back can get out the water easily and mace the flight nicer
But do they spin in opposite directions?
😄😄😄😄😉😄😄
ProjectAir a excellent comment was explaining your longitudinal stability issue, you also have to tackle the lateral stability of the boat.
A rule of thumb would take into account the radius of the foil (more or less the U or V shape that you have) and the height of the CG above the water. Then you should ensure that the radius of the foil is bigger than the distance to the water. This part is not easy to explain and a drawing would be better BUT :
Imagine a small angle of the boat to the left. Rotation is around the CG. If the radius is bigger than the height of the CG, the right part of the foil will rise above water and the left will plunge, creating more lift on the left of the boat and self correcting the attitude. If the radius is less the same thing will happen BUT due to rotation, the left part of the foil will be at best under the CG, at worst, on the right part of the boat, increasing the roll!
Hope it’s clear and will help you.
Also, once you make it fly, add as much weight as you can so you can barely take of at full throttle. You’ll have more inertia and pleasure to drive it.
Hey! I'm 17 years old and I've learned a lot with you thank you for everything and I just wanna say hello from 2021.
I'm studying electronic engineer and I wanna be an aerospace engineer. I built my first plane when I was 13 years old and please continue making more videos.
Hello from Colombia!🇨🇴
Long comment, I know, but I've studied hydrofoils in-depth, so hang around. It will be absolutely worth it. Here goes:
The following statement is the secret to achieving a successful hydrofoil: ***Because of the shallow V of the foil, the usable lifting area of the foil changes, depending on how much of it is in the water or not.***Consider the implications of that statement: The faster the boat goes, the more lift the foil creates. The more lift the foil creates, the more the foil rises out of the water. And the more the foil rises out of the water, the less lift it creates. Relative to the weight the foil supports, too much lift, and it rises higher, creates less lift, and sinks down. Too little lift, and it sinks lower, creates more lift, and rises up. This is a self-stabilizing system.
On the other hand, the rear foil is continually submerged in the water. This means (for a constant speed), the lift developed by the rear foil depends exclusively on its angle of attack in the water. Thus, when the boat pitches up, the foil pitches up and produces more lift. When the boat pitches down, the foil pitches down and produces less lift.
Now consider the hydrofoil as a whole. As the front foil creates more lift, the foil rises up in the water, causing the boat to pitch up. As the boat pitches up, the rear foil pitches up and creates more lift, causing the rear of the boat to rise up. The key is to place the CG just right such that the lift from both foils balances the weight and CG of the boat.
This is how you create a stable hydrofoil:
1. Physically set the incidence of the front and rear foils to be identical, and adjust the thrust angle of the motors to minimize the downward pitching moment they create.
2. Calculate the surface area of the area of the portion of the front foil that is underwater when the front foil is 1/2 way out of the water. (I'll call this Af)
3. Calculate the surface area of the rear foil. (I'll call this Ar, and call the distance between the foils L.)
4. Find the location of the CG that puts an equal load on both foils using the following equation:
Distance from rear foil to CG = L * (Af / (Af + Ar))
5. As the boat is foiling, use very small adjustments to the angle of the rear foil to adjust the flying angle and flying height of the model, accommodate for the thrust angle of the motors, etc.
Example:
Area of submerged portion of the front foil: 30cm^2 (Af)
Rear foil area: 15cm^2 (Ar)
Distance between front and rear foils: 30cm (L)
Find the distance from the rear foil to the CG (D)
D = L * (Af / (Af + Ar))
D = 30 * (30 / (30 + 15)) = 30 * (30 / 45) = 30 * 2/3
D = 20cm
The result is the CG should be 20cm ahead of the rear foil, and 10cm behind the front foil.
This is how you create a stable hydrofoil. Notice also the implications of the above formula: If the front foil has twice the area of the rear foil, it will carry twice the weight. Secondary to that, notice that when the boat is stationary, significantly more of the front foil will be submerged than what you calculated. More area = More lift. Thus, as the boat accelerates from a standstill, the fully submerged front foil will create more lift than it needs, lifting the front of the boat out of the water first. As the boat pitches up, the rear foil is allowed a higher angle of attack, and thus it lifts the rear of the boat up. And voila! You are foilborne! It is as easy as that.
But what do I know...? I'm just an engineer who wrote an entire research paper on the history and dynamics of hydrofoils.
Thats pretty cool i didnt know there was a science to it
im guessing this is for static hydrofoils, would the calculations change if you had a computer controlling the pitch of the foils?
Hey, massive thanks for this ^^.
I very much appreciate the time to go through this here and provide some hydrofoiling wisdom. I'll definitely be using that formula to properly setup and tune my new hydrofoil as soon as we have some better weather. I now realise I had a few misconceptions about how you get into a state of being 'foilborne' using the elevator. I was coming at it with very much an aeronautical perspective. That's probably why I aimed to get the CG over the front foil too which I realise now was pretty wrong judging by your calculations!
Looking forward to taking this to the next level. Thanks again!
Cheers,
- James.
I'm glad I could help you out. Of note, because this is changing the dynamics of the foils, you might find the boat is more stable with the front foil much farther forward, like 2/3 or even 3/4 of the way up the boat (depending on what looks most aesthetically pleasing, of course). It's like extending the wheelbase of a car, and as a bonus, it will make getting the correct CG placement much easier, too.
I realized when I wrote the research paper that you cannot necessarily treat the hydrofoil like an underwater airplane, because both surfaces must create upward lift. It's more like those old free flight models that used a lifting tail. The CG on the models is seems impossibly far aft-behind the TE of the wing even. But because math and physics (which I won't go into here) it works.
Cheers!
-Dave
@@GunganWorks Has any active stabilization been done on any hydrofoils. Like a simple PID tuned system inside a "flight controller?"
First, good try! I really want to see it perform on a calmer day.
Second, you're fit! I'd be still sitting on the overflow.
Third, we should do a challenge or something
Ivan Miranda collab needs to happen
@ivan we need you to build n hydrofoil airboat tool!
The screwdriver hammerer guy himself
sorry to be so off topic but does someone know of a way to get back into an instagram account..?
I stupidly forgot the login password. I love any tricks you can give me!
@Ronan Maison Instablaster :)
OK, bit of advice I gave in a community post, it's worth repeating here, "don't forget the rescue boat". Oh, and another bit of advice, "don't go near water without your wellies". Keep them coming, Merry Christmas.
Dude, your channel is so awesome and so underrated. I hope you hit 100k subscribers soon!
You’re the most original person I’ve seen so far in UA-cam this week. Congratulations 🎉🎊🍾
Just found this channel by pure accident and subscribed. Reminds me of the very much simpler and cruder experiments we tried 60 years ago when r/c was expensive and cumbersome and model aircraft were still wood and tissue and powered either by elastic or tiny, glow-plug engines. Never managed to get a hydrofoil to actually lift. Yours is brilliant. Are the air screws ‘handed’? Also, the athletics were admirable. Great fun. Thanks.
Impressive bridge climbing parkour nice one.
It even sounds like a boat. Well done.
Having lived all my life at a shipyard. I think i can safely claim that a long pole with a hook at the end is the best tool for resqueing stuff out of the water. For the size/weight of these RC boats, a telescopic pole like the ones window-washers use, would probably be the best choice. They are low weight, and only about 1.2 to 1.5 meter long when folded, so easy to transport.
The Cybertruck just got Better! also...
First!!!! Yes!!!! Finally!!!!!!
FINALLY!! Thank you man, been waiting so long.
Edit: 9:30 Holy crap dude you’re strong!
Thanks for watching! 💪😆
Makes me think about the evolution of Aeroplanes. Nice job, you need a pair of Wello’s
Nicely done James! I love the way a futuristic hydrofoil lends itself to the aesthetic of the Cybertruck.
A more elegant solution to the "nose down" behaviour would be to have a negative angle of attack for the motor, thus compensating for the propeller being mounted so high. Have a look at the bixler 3 plane for examples.
Alpem_Warrior yep that definitely would have helped to have an adjustable ‘head’ on that mount, but alas we were in the field with just a screwdriver to attack the elevator with 😊
@@Project-Air haha no worries. Great video!
@@alpemxyz Thanks
Just a thought, do the props on the mk.2 counter rotate? With the setup on mk.1 the motors cancel each other’s torque, if the props on the mk.2 turn the same direction i would guess that the torque could cause the instability.
It looked like you could relax the elevator some and maybe keep the front hydrofoil lower in the water. It only needs to raise the hull off the water surface.
Great project!
The first version sounded amazing
Keep it up James! This is very interesting would love to see a version 3!
The problem is the thrust angle. It should be angled in direction of the CG. That's why the angle you had to put on the tail was to big, and the back didn t get out of the water.
Hmm, not really sure about that. If anything I think the high moment from the elevated thrust line would force the nose down and lift the rear up - a little like how the hydroplane I built last year worked.
@@Project-Air Gungan works explains very well how it works and he also speeks about thrust angle. You need to angle your motors
@@nathanbarraud4349 I see what you mean - I'll make sure to do some more tests and try altering the thrust line sometime soon.
What does that exaclty mean, being angled in direction of the CG? Closer in line with the CG or really angled towards the cg? Just interested :)
@@MrKipKonijn I think he means having the motors tilted down so they push though the CG and down cause the front to push down. I guess potentially having the motors tilted down would mean the front wouldn't be pushed in to the water so the elevator doesn't have to work as hard in the opposite direction. I do agree with James though.
Looks like you need a foil about twice the size as that one for that boat. Also, if you go to your local hobby shop and get some lead stick on weights and place them on the bottom center of the foils at the lowest point, that will also make it much more stable. I would also consider making a design where you have another foil just like the one on the front but placed on the rear right in front of your rudder. Keep your rudder/elevator foil on there too for stearing, this will help keep the rear of the vessel up out of the water. Good luck!
Very nice.
If I had a lake close by I`d probably try to make one.
Couple of points which may help.
When you had the 2 motors on the carbon, they were rotating opposite, so all good, but when both facing forward, looks like you were getting torque roll.
Try making one motor rotate the other direction. i.e. one clockwise, and one counter clockwise.
Also, mix in some "differential thrust" on the motors, as this will work like a rudder also.
good luck, looking forward to next version
you maytry to put the CG in between the two hydrofoils , such that they'd both be lifting , instead of the front one lifting , and the back one producing downforce as it looked to be like in the first prototype
It's complicated by the rotation caused by the airscrews thrust being high above the drag. How to counter that without messing up the pitch control? I can't figure out how to balance the two.
@@bikeforever2016 batteries at the back would couteract the nose down pitching moment induced by the thrust (maybe 😂) . The back wing would have to lift up more than the front one , making the whole boat a canard-style boat , relying more in the back , and maybe using the front one for pitch control .
That would have been an interesting idea to test on the MK2, I should have tried it. Was thinking at the time of keeping it more like a standard airplane configuration though.
If you're really motivated one of those Manly hydrofoil ferries is moored opposite my place on Sydney Harbour and for sale. The boat itself is cheap(-ish!) because the RR engines need work - and they are very very expensive.
add a second foil at the back or maybe add control surfaces on the foil to keep it from rolling
Take version 1, try to move the motors further back and as low as possible. Change the thrust angle of the motors so that a line of the thrust angle goes through the boat at a point about 2/3 of the length measured from the rear. Make sure you have small increments of control for the rear foil so that as the boat rises out the water you can cut back on the angle of the rear foil. At the desired attitude of the boat hydroplaning, the front foil should still have a slightly upwards tendency to make it stay out of the water. Make sure the front hydrofoil is not too "pointy" into the water as this will cause instability as it rises out of the water. Good luck but hope to see you succeed with this one!
Some things you might consider for the Mk3.
1. Return to the center engine pylon with a "push-pull" configuration. That _seemed_ to be much more stable, although that might be an illusion because of the weather.
2. Shorten the "legs" on the foils. I doubt if you really need _THAT_ much clearance when at full speed. Unless, of course, you're trying to clear out the water weeds when you're at slow speeds!
3. Follow the design advice from Gungan Works :D He _REALLY_ seems to know what he's talking about!
Seems like some elevons and an imu on the main foil might help. Or at least some wash in on the main foil to increase roll stability. Also, perhaps decoupling the rear foil from the rudder. I tend to try to keep my inputs as independent as I can for simplicity's sake. I think using differential thrust for steering is going to be a losing battle because you've got a lot of vertical surface area cutting through the water. Remember that water is 100X the density of air.
I really like this project James. I think you might need a normal hulled tug boat with a lot of torque that can go out to save the hydrofoil to make your testing easier. Also it might be fun to add aileron as I believe I have seen that on some hydrofoils so they can control roll. P.s. Some sweet boulding on that bridge.
Are both props Turing in the same direction? Looks like when you are applying the power the boat is torque rolling. Spins the props in opposite directions so they cancel each other out..
The one thing I would say is to cut the flat section on the front foil out as it produces to much lift causing the foil to leave the water. The diagonal parts should easily be able to lift a boat of that size and will have self stabilising characteristic.
I’ve done a lot of theory work with foil and have sailed hydrofoiling boat like the vampire project so you know the advice has some backing
i might have an idea to solve the turning, have you tried to install a water jet instead of props?
i think thats what most hydrofoils use anyway? worth a thought.
How about trying propellers that turn in different directions (left one goes clockwise; right one goes counter clockwise) if you haven‘t already.
U R SOOOOOOOOOOOO UNDERATED
Should have read Gungan's comment first, eh! The math' behind my thought! Nicely put Gungan, thank you :)
nice adventure, huge improvements on the channel over the past 12 months
great footage like the gym exercise and cliff hanger on the bridge. You first might need a real rescue boat for your boats that brings you to the places were your models stranded.
and historical imperfections or so was a great quote
all the best
Really pleased you think that! Thank you. Yes I probably should have brought my inflatable dinghy. 😂
Are you using contra-rotating motors/props ? If both motors and props are rotating the same way there maybe a torque reaction causing the rolling instability when trying to plane ?
Just a suggestion but try putting two motors at the front outer edges pulling rather than pushing and keep the c/g behind midships.
Try going back to the contra rotating props, because maybe the two separated props are getting a different amount of air flow, and ther high mounting position mite be making it roll
it is rolling at full throttle because of p-factor of the props. your first boat was stable because it had push and pull props counteracting the p-factor. try using counter-rotating motors and props with the right motor rotating to the left and the left motor rotating to the right. Check out the P-38 design to understand what I am talking about. Although the P-38 had counter rotating props to the outside not towards the inside as I am suggesting. Concerning the wings they should be mounted further back closer to the center of the overall length of the boat and be deeper in the water. The rear wing should be larger for better control
Fantastic job, dude! 😃
The only thing I could think of is the direction of the motors. Make sure they're contrarrotating(?). 😊
Happy holidays!!!
Might the boat also have tendency to roll because the propellers are rotating in the same direction, thus creating a torque that rotates the boat? Maybe counter rotating propellors will help a bit.
I'm impressed with how smooth the Mk. I was in the GoPro footage. I hope the kinks get worked out of the Mk. II, because it looks delightfully mean.
Thanks man, yeah I like that look too 😎
Cool project!
Do the motors spin the propellors in the same way? If they do, then the torque from them could be tilting the boat over. What I suggest is that you have the motors spin opposite ways and use differential thrust with them. (If you haven't already, hard to tell in the video)
hello how do you waterproof your balsa wood ? what is the purpose of sandling sealer ?
Do you think it could be the centrifugal force of the props that is causing the boat to tilt ?
Damn im impressed with your free climbing! Well dun! Awsome video as well! Lol
Thanks haha, climbing is another of my interests.
James, you certainly work extra-hard on your craft! Kudos! How many RC Pilots have to do pull-ups during enjoyment of their hobby? You are one of the few brother! May I recommend a fishing pole with 25lb test and a noose loop at the end for the future subjects heading towards that overflow..?
Keep up the GREAT WORK!
Best regards and Happy Holidays!
-Dave
Thanks Dave, happy holidays to you too ☺️
You could add a couple of stabilizers hooked up to a gyro or flight controller to control the boats attitude a bit better.
+1 for your climbing skills
I think you should use counter rotating props. They should Help you eliminsting the role momentan that the boat has
Creative_stwb 1 they were counter rotating 👍
@@Project-Air
Okay thannks Form Clearing thwt Up
hey, thanks for your video. sometimes you learn more when things don't work out. I think you are almost there, it's a balance problem now, I think.
You do have the props counterrotating, right?
Agreed. Definitely contra rotate the props
Wernerrrrr yes I did 👍
on the second boat? because it looks like a lot of torque steer.
@@spud4242 Yes on the second boat too. It was very windy meaning the boat kept getting blown to the side.
Glad this was in my recommendation
Great video, keep up the good work! Nice design elements. 1 Q' You did have the rotors (model 2) counter rotating? For the Hydrofoil action ... If you have the ability to change the angle of the attack of the rear hydrofoil you will be able to rise and then keep it in the elevated position. A 3rd control channel, if you like. A 4th control channel for the front hydrofoil would be the ultimate. For operation a mix of Rear and Front hydrofoil through a lot of experimentation should be possible. Great potential for an autonomous vehicle project!
Thanks for the comment! 1) Yep they were counter rotating on the MK2. (2) Yeah I realise now I misunderstood how to control the elevator to get the model to 'plane' properly haha - although I think the new MK2 did show some evidence of the rear coming out of the water (3) A 4th channel for ailerons would be great, but also complex which is why I stuck to keeping it simple. ☺️ Cheers.
U r the best 👍👍
Thats a good design now center the power to cg in the middle
are the props counter rotating? Could torque be an issue?
LOVE SO MUCH THANKS!
Who else thinks he should go to Ninga Warrior UK 9:32
I think you could make like ”winglets“ that is going going to hold it steady while making a turn and give more lift
So you designed a rescue boat that needed rescuing? Which brings up a real quandary (it might even be a dilemma); which comes first; the rescue boat or the boat for rescuing prototype rescue boats?? 🤔
Also, at least it was better than the Cybertruck launch--just don't throw rocks at it. 🤣
DeadlyDiddly I was thinking about the irony of the situation at the time 😂 Thanks man, I can imagine the Cyberboat would fair significantly worse than the Cybertruck when rocks are thrown.
The MK 2 looks really cool James, I'm sure you'll mod and tweak and tune it to perfection. It looks really strong too, so I'm not convinced it wouldn't fair better than Elon's _Armor Glass_ if stoned. 🤣
@@DeadlyDiddly Thanks!
@@Project-Air >>> Rescue Boat = _Canoe/Kayak?_
{On the UPSIDE, the UK does NOT have one water hazard that the place where I grew up -- Florida -- has: _Alligators_ 😊}
@@Allan_aka_RocKITEman Haha yes, although we do have the Loch Ness Monster 😉
I’m super late but could using a v-shape for the bottom front of the boat as to not catch air and force it down
I think you should use a control board to control those two motors
Do you put the blueprints together in CAD before cutting them out
1) Bring some rubber boots.
2) Bring a casting fishing rod to retrieve the boat.
3) Dual in line motors worked better
Lad, just set the GoPro on it at a higher pitch, that way it’ll keep the head of the ship down, and you’ll get some nice cinematic shots
Convair Sea Dart next ??
Well done with this. I like your perseverance. A bit more information on your thought processes with the designs would be good. Keep up the good work.
counter rotation props should help
What difference does the weight of the go pro on the front make
What is the foam you use?
I think, both motors didn't spin exactly the same rpm so it pushed one side down! The first motorconcept was better! Maybe 2 times 2 motors would be better!! Happy Christmas
this boat is looking less of cybertruck and more of nighthawk, btw try using differential thrust on the motors along with the rudder for additional control
Absolutely think adding differential thrust would be very beneficial. It's one reason I decided to go for this separated motor configuration on the MK2
What glue are you using there James?
the mk1 seemed to work decently, however, to have a balanced fly, I would have set the rudder with less tilt after lift off (to avoid the diving issue)
Great build... Are you using the k40 laser cutter engraver
I think it would be nice to revisit this project...
Broader hydrofoils angled with lesser incidence than they are at the moment,looks to me like it's stalling?
It could be the motors! A simple left torque and a right to counter act each other may be your problem! Looks the part tho :)
Because you were making futuristic builds, do you think you can make a plane with a forward swept wing? There was a video Real Engineering made about the advantages, and I think you should try it out.
Oooh good idea 👍 I might just do that
0:03 this week im James 🤣what about next week what you will be then?
haha, "Welcome back to Project Air this week. I'm James, and today..." Yeah I can see how that could be confusing. 😉
Nice video tho
It's odd but I actually like the cybertruck design more as a boat. Anyone else think the same?
ProjectAir: Why is the boat rolling when it comes out of the water
Me: its because of the wind you can see it on the water
Prototype = Swimming pool? Easier to rescue...
Una vez ha salido fuera del agua la proa y ya solo está navegando con el ala delantera deberías modificar lentamente la posición del elevador, sin bajar la velocidad, para conseguir que salga fuera del agua la popa también
You need a more powerful motor, because water is denser than air. That's why the mach 1 can't get its tail out of the water.
This is how the cybertruck should habe looked
yes... move the heavier part lower. then it will keel
Center the props lengthwise, in the center.
What's the best method to waterproof a 3D printed boat?
That boat should be called th cyberfoil
I think you need upthrust on the motors!
nice bro
Ok you need a boat hook and some wellies or waders...save getting wet all the time!
the props look like they have the same rotation. thuis could cause the problem use cw + ccw.
Wish I had something intelligent to say about the boat instead but I was pretty surprised by your climbing ability.
It needs a gyroscope to balance and avoid rolling
Why not a water propeler driven?