You need a Louver or a Strata cap which prevents debris from entering the fan with a tornado effect expelling the debris & dirt to the sides. They are used in aftermarket car car intake boxes for off-road vehicles. A topspin would work too. Check out Donaldson Filtering solutions. You may be able to 3D print one. They may even sell one small enough for your application. essentially they are pre filters but work with centrifugal force of air spinning like a tornado rather than a mechanical filter which can clog.
I think that you did a much better job with your choice of location for this experiment compared to the previous video. This time it was much more suitable for your experiment. And this time the difference in grip was very noticeable despite your clumsy handling and steering 😉 So my compliments for that. 😋 Sorry for you loss of the camera. Small tip, maybe next time you can turn that round track into an oval with some cones, creating a straight on the track, which gives you more data and more challenging conditions.
A firmer suspension could give you more downforce without dragging the skirt. Also for active downforce management you could increase the fanspeed when steering (if you can program that)
Actually, as you start to draw a vacuum, you will draw less power, as it's doing less actual work, so you could make a smart controller that indirectly senses how much of a vacuum you are pulling by monitoring draw, and automatically controls the throttle to try to always pull slightly less than the maximum vacuum, which should hopefully translate into the skirt riding just above the ground.
@@Nevir202 that's right, but needs a lot more engineering. I don't think my suggestion is a perfect solution, but it could improve the rideabiljty with little changes.
Dynamically controlling the fan speed based on laterally forces and / or skirt height may be fun. I would consider adding some small air inlets near the front of the skirt to keep it from sealing completely as the fan loses much of it’s suction when the air flow is reduced to near zero. Also a centrifugal fan would do well in this use case. Fun vid, Hope to see more on this topic.
Having a microcontroller that takes an input from an accelerometer and then varies the speed of the suction motor based on the lateral G's would mean that when the suspension in unloaded, the suction falls off allowing the car to attain higher velocity due to lower friction and then when the G's rise up (in a turn), the fan speed ramps up, increasing suction and pulling the car down and loading the suspension up providing more traction.
With a digital programmable remote control he can simply make the steering action also control the fan speed. With each steering input the fan speed goes up, regardless if it is steering to the left or the right. And with less steering action the input will be lower so there will be less fan speed. So there is no need for gravity sensors or an accelerometer at all.
@@insAneTunA That is a good idea, I did not know you could do that with controllers. The only downside is there are times where you do not want suction but you do want high steering angles. Such as low speed turning just to name one instance.
The trick to making that vacuum skirt work is to attach it to the wheel uprights, not the chassis so it stays at a fixed height above the ground no matter how much the car rolls/pitches. It'll let you run a softer suspension as well, which is almost always better.
Wouldn't doing that mean that the chassis of the car needs to be able to move up and down and tilt sideways inside the skirt? which in turn means you would have to make the skirt seal all around the chassis while not being attached to the chassis itself.... feels daunting to me :)
@@kenvanpassen9247 No the skirt that he's built would be the same, just attached to the wheel uprights rather than the chassis. But yes with softer suspension he's have to lift the chassis up a few mm's so it'd keep clear of the skirt in bumps.
By looking on the video, I have a feeling that you configured EDFs to suck air, but making them rotate "backwards" instead of mounting them reversely. Remember, blades have their shape and angle of attack to provide maximum thrust when they rotate in the direction they were designed to. So, by mounting them correctly, and powering according tho their natural direction of rotation they will produce much more thrust/suction :)
@@JMMC1005 Somehow I completely forgot to mention that this was intentional: I still got more than enough thrust/suction from the fans with the blades the less-optimal way around (only needed about 30% throttle) while still having the EDF blades visible, so it looks cool for the thumbnail (important for UA-cam, let's be real!). Nice one for noticing though!
@@JMMC1005 Believe in JESUS today, confess and repent of your sins. No one goes to heaven for doing good but by believing in JESUS who died for our sins. Hell isn't fun. GOD loves you soo much unconditional❤🙌❤😌
@@Project-Air Are you planning to implement huge wings together with this fan on an RC car, and maybe a modified body shape ask as to improve airflow speed and smoothness. Also, as other comment threads have mentioned, being able to programme the fan speeds would be beneficial.
The Chaparral 2j had skirts that were stiff but moved. They worked with the suspension to keep a set height from the ground. Also you could have the tray adjustable for and aft to balance down force. Too much push? Move it forward. Fan cars are great concepts but require unrealistic flat and clean surfaces.
yeah, i thought he was gonna mention the 2j, the absolute beast of a car that could probably generate enough downforce to stop upside down... too bad it was unreliable as heck
I think it would be worth looking at the fan as a mechanism to move air over diffusers and venturi tunnels under the car at a faster rate of speed than the car is moving. This is the actual primary purpose of blown diffusers and of the bt46b's fan. It wasn't designed to be a static pressure device like a vacuum. Think of the design more as an upside wing in a wind tunnel. The wing will produce lift, or in this case downforce, even when stationary by having the air pulled past it by a fan. It makes for much more efficient, meaning more downforce to drag ratio, than a vacuum design.
This is what I was thinking. The whole point is to take advantage of ground effect, which he acknowledges, but never actually makes any attempts to use...
That's what i thought too. The fan car in f1 would suck in air through the front and blow it out the back to make the air underneath move faster, creating a low pressure zone.
Suggestion - add an inertial switch or accelerometer linked to the fan speed - increase grip from skirt when cornering, decrease drag from skirt on straights
Believe in JESUS today, confess and repent of your sins. No one goes to heaven for doing good but by believing in JESUS who died for our sins. Hell isn't fun. GOD loves you soo much unconditional❤🙌❤😌
Hey bro, just wanted to say how professional your videos are now. Great sound and lighting. Youre more calm and confident, with great shots and editing. Just like on TV. If youre doing this all yourself well done. Wish you well on your career. All the best Kieron
Im a photographer ... so would be interested in your gear - which camera, led lighting, mic you use please. oh, maybe a link to locked google sheet in the description perhaps. That would be cool.
I’m sure you got inspiration from f1 including the last car video. I’m a huge F1 fan and all I can say is great job trying to make a ground affect car!
Maybe just carry forward the trend & add stuff like bargeboards, venturi tunnels, diffusers etc like a F1 car? Would be awesome to see you make something that has them all working together Edit: Active suspension & active aerodynamics would be so cool as well
There was a car in GT6 that had this technology too called the Chaparral 2J '70. The design wasn’t allowed after a couple races irl because any driver caught behind it literally has to eat road dust.
It would be very interesting to see a sensor used to sense the distance to the ground and the Gs on the car to drive a PID control of the fan to get maximum grip when needed without having the skirt contact the ground. You could also designs a skirt that used a Teflon material in a guide that is free to move up and down to create a near perfect low friction seal.
Chaparral 2j used this same concept. Their skirt used cables and pullies to maintain a specific height independent of the body of the car. Cool video!!
Awesome build! What about testing attaching wings directly to the wheel hubs like they did before they banned it. This keeps the pressure directly on the tires so you can run softer suspension and have more mechanical grip.
This new generation of F1 cars also use ground effect to generate downforce. It’s really interesting to see the different designs and strategies they use to seal de underfloor to preven purposing. I’m loving this aero centered videos. They help to understand this concepts and have a bit of a better view when watching races
Would be informative to show the lap times with and without suction. Also why not to disable the fan - do the lap - enable the fan - do the lap, so the testing is more accurate
Believe in JESUS today, confess and repent of your sins. No one goes to heaven for doing good but by believing in JESUS who died for our sins. Hell isn't fun. GOD loves you soo much unconditional❤🙌❤😌
The test would just show how the mods affected the car's performance from stock. Added data but nothing that would help the project far as I understand. I'm not the engineer type to tell how this would be applicable.
If 23 years as a airline aircraft engineer and crazy micro jet engine home builder has taught me one thing...its that you've installed the fans backwards and are running them in reverse. They'd work a lot better installed and running in the right direction. I am impressed none the less. 🙂🇦🇺
They still have blades as im sure your aware based on the quotation marks. The air would still have to travel through the blades so the same problem still exists.
The original was the Chaparral Fan Car - 2J in sports car racing. The engineering behind these cars is nuts! Not just a fan on the back way more than that
The pressure from the system is pushing down your rear wheels more than your front ones. Put the air intake closer to the front of the car and it will push the wheels that actually steer into the ground harder, and will help under steer. A front bumper mounted spoiler will also help push them into the ground. You can help prevent the skirt from hitting the ground by setting limits on the suspension end points. Hope this helps _ automotive project manager, JD Power :)
edit: I see this was already recommended :p A thought: Depending on the hysteresis between fan power and fan rpm, if you could have the fan run relative to steering input (the more you steer, the more the fan ramps up) you could perhaps gain some more straight-line speed and maybe get some better battery life as well. That is, only use the fan when it is needed.
7:43 this was a big problem with the Brabham fan cars and part of why the other teams wanted them banned. The debris they sucked up created a major safety issue for the drivers behind them; think what happened to Felipe Massa.
Hey Im in 12th grade and as my final, im building a similar car and i will conduct several experiments researching the effect different factors have on grip. One of the thing i want to try out is how downforce affects grip. I have some questions: - How much power did your edf use? - How big was the battery powering the fan? / how long did the fan run? - Did you use the same battery to power both the fan and the car itself? Any help is much apprechiated Thanks
I appreciate that your plug for NordVPN didn't play into the "it makes your data more secure!" nonsense, but focused on the benefit of being able to access other regions' streaming materials. Cool cars by the way 🙂
Doubt a cyclone would work , but with a bit of trickery you might accomplish the effect. Since power and efficiency of the fan aren't major concerns, baffle the suction such that it's spread among multiple points, and the suction is parallel to the bottom of the car. With no direct upwards suction, it would be hard to lift anything off the ground. You could also make the inlets small enough slits that you aren't worried about anything big enough to cause damage passing through them, say 3mm openings or something like that?
The EDFs are the wrong way round. They are much more efficient when driven in the right direction. And maybe a blower style would be better for this purpose because EDFs have such low static pressure.
Very cool- I think the biggest short-term gains would be fixing the skirts up. You're already printing it, so some printed sliding skirts with small flat springs could work well. This would make it a lot more versatile Suspension is another one- maybe stiffen it up a bit so you don't have so much travel for the skirt to contend with The ultimate solution is mounting the vacuum plate unsprung. This needs to be able to flex with suspension travel, and still have a bit of movement to cope with imperfect surfaces, but takes the soft suspension out of the equation entirely. If ytou wanted to take it to the extreme something like a 1/12 pan car could be ideal. They're already very low, have lots of surface area, and nearly locked out suspension
It seems like the past of formula 1 was a big list of trying things, new modes, projects, concepts and thank you to this videos everybody can watch that, and learn, thank you Guys!! 👍
Multiple of the 70's F1 cars used thickly set bristles as skirts. They were stiff enough to allow creating a somewhat permeable membrane, but soft enough to bend back when contacting the ground. They were probalby the best middle-ground solution between optimal downforce and creating too much downforce, increasing rolling or even drag resistance.
I recently thought of building a similar RC car! And I would never have guessed about the dust problem just by thinking about it😂Thank you for the wisdom!
Very cool little project. I'd suggest to enlarge the area of the mesh and maybe tinker with the center of suction as needed. But the biggest potential I guess is in skirts that can slide up and down to allow for proper working suspension and minimized drag from the skirts. Cheers
You should try blowing air past the hole and creating a low pressure area. This is used in garden vacuums to suck debris up into the bags. The plus of this is that your fan won’t get clogged as you are not sucking via the fan.
Maybe already commented: I believe your downforce is being reacted on the rigid "skirts" rather than going on to the wheels to generate grip. Skirts are supposed to slide up and down so that they don't transfer vertical force (so it doesn't take it away from the wheels, grip). Right now it looks like you do have some additional grip because you have some additional compression on the suspension but then you bottom out the "skirts" (it's really just the body of the car) and you dont get any more grip, just more drag because any additional suction goes to the skirt/body (not the wheels). This is why you found a happy medium in the fan speed. If you remove this limitation you could increase grip further. You could try stiffer springs so more load goes to the wheels, higher "unsuctioned" ride height or inplementing and actual sliding skirt. Awesome video, really like the experiment!
I’ve watched a fair amount of Gordon Murray videos. My takeaway is the fan in his fan cars weren’t directly sucking the car to the ground. Instead they were designed to augment aerodynamics by managing turbulent airflow and discarding it out the back. The fan in his T.33 hypercar runs at relatively low speeds to accomplish this. People assume his cars are vacuuming themselves to the tarmac but if that were true the drag this creates would make the racing cars too slow to be competitive. The fan is about managing airflow.
IDK how much time you spend reading comments from non-paying customers, but here goes!- Adjusting the downward suction to reduce drag is folly. You’ll never find a sweet spot that way; only a disappointing compromise. What you need to do is keep the shocks from traveling beyond the point where it’s just about to touch the ground. This principle should help in all kinds of situations. Good luck, (and thanks for providing videos that me AND my wife enjoy!) 😇
I've seen a few people mention this, but I want to say it again just so you hopefully see it. Right now your suction device is connected to the chassis of the car... which... there is nothing wrong with that... it works, but this relies on the suspension being the perfect height and spring rate to keep the skirt just a hair off the ground at all times to keep suction going. This is very difficult to do, and, if the solid skirt bottoms out on the floor, then you don't have the full force of the suction giving you traction, but you only have whatever the spring rate of the suspension is giving you for traction. Instead you need to figure out how to connect the skirt to the uprights of the tires in some way. This way the suction force is directed directly to the tires of the vehicle without effecting the suspension at all. This will also mean maintaining the proper height for the skirt will be much easier as well as it won't move with the chassis of the vehicle. Once this is done, you should have maximum traction from a very good suction along with a much improved ride quality (not that that matters too much for an RC car, but still)
You could let the fan run backwards when steering angle is close to zero in order to clear debris off the sieve. That would require either enough negative suspension travel (to not lose wheel contact when the car is pushed upwards) or a flap on the rear portion of the skirt which opens outwards but not inwards, sort of like a one-way valve... otherwise you'll get the world's most unstable ekranoplan. But if that works, it would not only clean the sieve but even act as a (very mild) booster on straights. Also you could plaster the downside of your squishy skirt with steel thumbtacks on something like that. Would reduce ground friction a lot and not compromise the seal.
in f1 they used skirts that allowed for suspension travel with ground-effect, and they also used them in the chaparral 2j which is more like what you have here. I think your experience with worse times with minimal gains came down to the fact that you do not have those skirts, and the assembly for the vacuum hitting the ground too quickly. You could fix this by lifting the vacuum assembly and adding those to allow for more travel, and possibly stiffer springs.
One thing worth noting was the the bt46 and lotus cars only use skirts on ether side of the car to increase the vinture effect (sorry for spelling). You might be able to increase performance by making it narrow in the middle of the floor and wider at each end as well as using a rubber skirt on both sides
I enjoy these videos so much. I’m probably like 20 years older than you, but I’m constantly learning from all these amazing experiments. I wish I had as much creativity (I’d be happy with one tenth of it!) :)
The original fan car, the Chaparrel 2J had a moveable skirt that was attached to the lower control arms of the suspension so only the low profile tires were a variable in how high the skirt was off the tarmac. You could limit the suspension travel to this height and use some firmer tires to keep the skirts off the ground.
the ideal adjustment to this would be to have a gear which turns from like 10% to 100% to that wheel which controls the fan speed, which you would change for gears and a motor turning them with another cog. This could be controlled remotely to allow faster straight line speed and to be turned up before breaking for corners.
IIRC the BT46 initially had the same problem of sucking itself down to the track and rubbing, but they solved it attached the vacuum chamber to the wheel hubs instead of the chassis. That way the suspension wasn't compressed by the vacuum.
If you ever try to optimize it, you should go back to flexible skirts. Because as soon as the hard one hits the ground, it stops you from adding vertical force to the tires and therefore adding grip. A harder suspension is also an option
you might consider a circuit to tye the fan in with the turning only. or increase pressure in the trurns, and decrease it on the straightaways. cool video, great job!
You need a Louver or a Strata cap which prevents debris from entering the fan with a pre filter tornado effect expelling the debris & dirt to the sides. They are used in aftermarket car car intake boxes for off-road vehicles. A topspin would work too. Check out Donaldson Filtering solutions. You may be able to 3D print one. They may even sell one small enough for your application. essentially they are pre filters but work with centrifugal force of air spinning like a tornado rather than a mechanical filter which can clog.
The Chaparrel 2J (1970) was the first car to do this, 8 years before the Brabham BT46 (1978). The chaparrel was banned from all formal national and international races after one season at the american can-am races where a number of drivers complained about its vastly different racing lines.
I have 3 suggestions: - Use a "bladeless" fan (with actual blades perpendicular to the actual flow) to avoid clogging,, so to eject away whatever is on the ground into the air, gravity will do the rest (or put a meshed bag on the output if making a vacuum cleaner is your goal). You may need 2 EDFs to get the same power, tho. - Make the downforce proportional to the speed to avoid crushing the skirts and let the tyres make their job: more force at high speed, less force at ow speed. I suspect it's an exponential function, tho, so the speed limit is at your EDF's limit. - You could print your skirt in TPU to make it flexible and avoid permanent deformation with electrical tape and duct tape, or just sculpt rubber from a tyre. Ideally, sandwich some metal mesh from your sieve in elastic material to add some strength (like in tyres)
in a future iteration id recommend opening the front of the skirts and the back of the skirts part of the downforce comes from the air creating that low pressure zone which is easier at the front without the skirt would add less surface friction when the skirts glide across the surface
The dirt was also the issue with the Chaparral 2J. The didn't use a mesh to filter, so they used to thro rocks behind the car. It was band for that reason.
Try adding a few ball bearing beads embedded in the skirt so they keep it just slightly off the ground. This will dramatically reduce drag without having to perfectly dial in the fan speed.
Perhaps make a control loop with monitoring wheel speed and steer angle. So at low speed where you want to accelerate and not want the drag (Launch or out of a hole). And maybe have it tied in with steering, higher fan speed with higher steer angle to stick around an apex. Maybe have some brushes around the side like from a hoover.
4:03 omg you just gave me an idea how I can make a cheap microphone metal mesh instead of buying seemingly non existing metall mesh on Amazon thanks a lot xD
Every time I see someone do this, I'm always reminded of the line follower robot competitions in Japan; the winners always use four quad props, in reverse, so it's essentially blasting air upwards and creating downforce. At least it won't be vacuum clener anymore.
if you could find a way to make a through-hole from the front to the back of the vehicle, put your fan at the back of that hole (rear end of vehicle) then open a large hole in the middle that attaches to the vacuum apparatus, I think you would have success, as that hole leading to the vacuum now has plenty of suction coming directly from the atmosphere instead of on the ground, this suction would come from the “Venturi Effect”. That being said, holy moly..nice work so far sir.
Hello from France 🇲🇫 You are in the good way to explore this strange set-up. Sorry for camera but all genius encounter problems. You probably should explore the mass position for better handling as you have lot of weight on extremety and for better habdlig you have to put the max possible in center of car. Freeing the front for turning and the rear from centrifugal force during turn. Also possible option could be to have a rigid suction chassis and a smooth lip around it that could be scratch by road Ithout transfer the contact vertical force to car (out of damper as it's the chassis) this vertical impact will light the down force and could be the moment of loosed handling if you are on hard turn. Way more to explore Way more to fun Way more to add success 👍
Big shout out to Engineering After Hours - his fan cars are some of the fastest electric vehicles in the world! ua-cam.com/users/EngineeringAfterHours
Great work on this one! I love the direction comparison as well.
You need a Louver or a Strata cap which prevents debris from entering the fan with a tornado effect expelling the debris & dirt to the sides. They are used in aftermarket car car intake boxes for off-road vehicles. A topspin would work too. Check out Donaldson Filtering solutions. You may be able to 3D print one. They may even sell one small enough for your application. essentially they are pre filters but work with centrifugal force of air spinning like a tornado rather than a mechanical filter which can clog.
try to fix the cam, lock easy
I think that you did a much better job with your choice of location for this experiment compared to the previous video. This time it was much more suitable for your experiment. And this time the difference in grip was very noticeable despite your clumsy handling and steering 😉 So my compliments for that. 😋 Sorry for you loss of the camera. Small tip, maybe next time you can turn that round track into an oval with some cones, creating a straight on the track, which gives you more data and more challenging conditions.
Could you build more rockets? Those are very fun videos to watch and you do a good job on them.
Early testing seems to have revealed you were on track to create the worlds fastest roomba haha
You just now need to explore how Dyson keep their suction constant and free of obstruction.
@@xdragon2k They use a secondary vacuum chamber with a tornado effect to bring the debris to the edge.
Also known as a VROOM-ba
@@masterimbecile vroomba go brrr
@@JusticePreyHDM attach a remote explosive and you got a boomba
A firmer suspension could give you more downforce without dragging the skirt.
Also for active downforce management you could increase the fanspeed when steering (if you can program that)
^ this one! Please take it further!
Actually, as you start to draw a vacuum, you will draw less power, as it's doing less actual work, so you could make a smart controller that indirectly senses how much of a vacuum you are pulling by monitoring draw, and automatically controls the throttle to try to always pull slightly less than the maximum vacuum, which should hopefully translate into the skirt riding just above the ground.
@@Nevir202 that's right, but needs a lot more engineering. I don't think my suggestion is a perfect solution, but it could improve the rideabiljty with little changes.
Dynamically controlling the fan speed based on laterally forces and / or skirt height may be fun.
I would consider adding some small air inlets near the front of the skirt to keep it from sealing completely as the fan loses much of it’s suction when the air flow is reduced to near zero.
Also a centrifugal fan would do well in this use case.
Fun vid, Hope to see more on this topic.
further to this making the skirt and aero unsprung to you can run the fan at max without any risk of grounding out
Having a microcontroller that takes an input from an accelerometer and then varies the speed of the suction motor based on the lateral G's would mean that when the suspension in unloaded, the suction falls off allowing the car to attain higher velocity due to lower friction and then when the G's rise up (in a turn), the fan speed ramps up, increasing suction and pulling the car down and loading the suspension up providing more traction.
Turbo lag may be a problem. How fast can the fan spin up? The car needs down force at the start of a turn.
It could just use stearing input with suction, More steer
I wonder if an adjustable vent could help with spin up delays.
With a digital programmable remote control he can simply make the steering action also control the fan speed. With each steering input the fan speed goes up, regardless if it is steering to the left or the right. And with less steering action the input will be lower so there will be less fan speed. So there is no need for gravity sensors or an accelerometer at all.
@@insAneTunA That is a good idea, I did not know you could do that with controllers. The only downside is there are times where you do not want suction but you do want high steering angles. Such as low speed turning just to name one instance.
Map a button on your controller to spin the fan in the opposite direction. This helps in disposing the dirt getting stuck.
sky effect
And In bonus, make the car fly!
He’s gonna have to change the whole ESC to do that
@@MatthewNovoselskiy most escs support reverse just have to program it.
69th like. Nice
The trick to making that vacuum skirt work is to attach it to the wheel uprights, not the chassis so it stays at a fixed height above the ground no matter how much the car rolls/pitches. It'll let you run a softer suspension as well, which is almost always better.
Wouldn't doing that mean that the chassis of the car needs to be able to move up and down and tilt sideways inside the skirt? which in turn means you would have to make the skirt seal all around the chassis while not being attached to the chassis itself.... feels daunting to me :)
@@kenvanpassen9247 No the skirt that he's built would be the same, just attached to the wheel uprights rather than the chassis. But yes with softer suspension he's have to lift the chassis up a few mm's so it'd keep clear of the skirt in bumps.
By looking on the video, I have a feeling that you configured EDFs to suck air, but making them rotate "backwards" instead of mounting them reversely. Remember, blades have their shape and angle of attack to provide maximum thrust when they rotate in the direction they were designed to. So, by mounting them correctly, and powering according tho their natural direction of rotation they will produce much more thrust/suction :)
This! He was losing so much efficiency by doing this. I'd be surprised if he was getting more than 50% of the EDF's normal performance.
@@JMMC1005 Somehow I completely forgot to mention that this was intentional: I still got more than enough thrust/suction from the fans with the blades the less-optimal way around (only needed about 30% throttle) while still having the EDF blades visible, so it looks cool for the thumbnail (important for UA-cam, let's be real!). Nice one for noticing though!
@@JMMC1005 Believe in JESUS today, confess and repent of your sins. No one goes to heaven for doing good but by believing in JESUS who died for our sins. Hell isn't fun. GOD loves you soo much unconditional❤🙌❤😌
@@Project-Air Are you planning to implement huge wings together with this fan on an RC car, and maybe a modified body shape ask as to improve airflow speed and smoothness. Also, as other comment threads have mentioned, being able to programme the fan speeds would be beneficial.
@@Project-Air Also yeah, while it's true that it would look better on the thumbnail, the sacrifice of performance is kind off off putting.
The Chaparral 2j had skirts that were stiff but moved. They worked with the suspension to keep a set height from the ground.
Also you could have the tray adjustable for and aft to balance down force. Too much push? Move it forward.
Fan cars are great concepts but require unrealistic flat and clean surfaces.
yeah, i thought he was gonna mention the 2j, the absolute beast of a car that could probably generate enough downforce to stop upside down... too bad it was unreliable as heck
@@akhil_kasiram and ass backwards to drive if it's anything like the Gordon Murray cars
I think it would be worth looking at the fan as a mechanism to move air over diffusers and venturi tunnels under the car at a faster rate of speed than the car is moving. This is the actual primary purpose of blown diffusers and of the bt46b's fan. It wasn't designed to be a static pressure device like a vacuum. Think of the design more as an upside wing in a wind tunnel. The wing will produce lift, or in this case downforce, even when stationary by having the air pulled past it by a fan. It makes for much more efficient, meaning more downforce to drag ratio, than a vacuum design.
This is what I was thinking. The whole point is to take advantage of ground effect, which he acknowledges, but never actually makes any attempts to use...
That's what i thought too. The fan car in f1 would suck in air through the front and blow it out the back to make the air underneath move faster, creating a low pressure zone.
Id love to know if it could drive on a ceiling [a flat one of course]
You could race it at the Guggenheim in New York!
There are RC cars that do this for very cheap on amazon :)
Suggestion - add an inertial switch or accelerometer linked to the fan speed - increase grip from skirt when cornering, decrease drag from skirt on straights
Believe in JESUS today, confess and repent of your sins. No one goes to heaven for doing good but by believing in JESUS who died for our sins. Hell isn't fun. GOD loves you soo much unconditional❤🙌❤😌
That would be so cool!!!
Hey bro, just wanted to say how professional your videos are now. Great sound and lighting. Youre more calm and confident, with great shots and editing. Just like on TV. If youre doing this all yourself well done. Wish you well on your career. All the best Kieron
Thank you Kieron
Im a photographer ... so would be interested in your gear - which camera, led lighting, mic you use please. oh, maybe a link to locked google sheet in the description perhaps. That would be cool.
ah piss!!! feel your pain on that camera smash
I’m sure you got inspiration from f1 including the last car video. I’m a huge F1 fan and all I can say is great job trying to make a ground affect car!
*Sad Chaparral Noise*
Can't fortget the 2j
I own those rc cars. Stiffening the suspension by twisting the screws on the shocks sona helps alot. Also putting thicker oil in the shocks.
Maybe just carry forward the trend & add stuff like bargeboards, venturi tunnels, diffusers etc like a F1 car? Would be awesome to see you make something that has them all working together
Edit: Active suspension & active aerodynamics would be so cool as well
or sex wheels
There was a car in GT6 that had this technology too called the Chaparral 2J '70. The design wasn’t allowed after a couple races irl because any driver caught behind it literally has to eat road dust.
Awesome! Love the timing with f1 starting last week!
Your workmanship is brilliant. The sieve install was testament to your attention to detail. Awesome to watch!
It would be very interesting to see a sensor used to sense the distance to the ground and the Gs on the car to drive a PID control of the fan to get maximum grip when needed without having the skirt contact the ground. You could also designs a skirt that used a Teflon material in a guide that is free to move up and down to create a near perfect low friction seal.
Probably easier to use a barometer than a height sensor.
Chaparral 2j used this same concept. Their skirt used cables and pullies to maintain a specific height independent of the body of the car. Cool video!!
Awesome build! What about testing attaching wings directly to the wheel hubs like they did before they banned it. This keeps the pressure directly on the tires so you can run softer suspension and have more mechanical grip.
4:42 I'm diggin the old iron you got there. None of this plastic disposable garbage, just an honest little Mini.
This new generation of F1 cars also use ground effect to generate downforce. It’s really interesting to see the different designs and strategies they use to seal de underfloor to preven purposing. I’m loving this aero centered videos. They help to understand this concepts and have a bit of a better view when watching races
So did the 70s ones and they abused it to near comedic effect lol
Great work on this one
Would be informative to show the lap times with and without suction. Also why not to disable the fan - do the lap - enable the fan - do the lap, so the testing is more accurate
Believe in JESUS today, confess and repent of your sins. No one goes to heaven for doing good but by believing in JESUS who died for our sins. Hell isn't fun. GOD loves you soo much unconditional❤🙌❤😌
The test would just show how the mods affected the car's performance from stock. Added data but nothing that would help the project far as I understand. I'm not the engineer type to tell how this would be applicable.
If 23 years as a airline aircraft engineer and crazy micro jet engine home builder has taught me one thing...its that you've installed the fans backwards and are running them in reverse.
They'd work a lot better installed and running in the right direction.
I am impressed none the less. 🙂🇦🇺
The fastest vacuum cleaner I've ever seen.
*Chaparral 2j has entered the chat*
The fastest roomba
@@daeshawnr2595 lotus 79 leaves the chat
6:09 The car went "Into the Nutzz!"
Love the video!
You could try a "bladeless" fan to solve you're blade snaping problem.
Like the Dyson fan? Complicated but good idea
They still have blades as im sure your aware based on the quotation marks. The air would still have to travel through the blades so the same problem still exists.
The original was the Chaparral Fan Car - 2J in sports car racing. The engineering behind these cars is nuts! Not just a fan on the back way more than that
Love your Mini man! It looks perfectly modified
The pressure from the system is pushing down your rear wheels more than your front ones. Put the air intake closer to the front of the car and it will push the wheels that actually steer into the ground harder, and will help under steer. A front bumper mounted spoiler will also help push them into the ground.
You can help prevent the skirt from hitting the ground by setting limits on the suspension end points.
Hope this helps _ automotive project manager, JD Power :)
edit: I see this was already recommended :p
A thought: Depending on the hysteresis between fan power and fan rpm, if you could have the fan run relative to steering input (the more you steer, the more the fan ramps up) you could perhaps gain some more straight-line speed and maybe get some better battery life as well.
That is, only use the fan when it is needed.
7:43 this was a big problem with the Brabham fan cars and part of why the other teams wanted them banned. The debris they sucked up created a major safety issue for the drivers behind them; think what happened to Felipe Massa.
Hey
Im in 12th grade and as my final, im building a similar car and i will conduct several experiments researching the effect different factors have on grip. One of the thing i want to try out is how downforce affects grip. I have some questions:
- How much power did your edf use?
- How big was the battery powering the fan? / how long did the fan run?
- Did you use the same battery to power both the fan and the car itself?
Any help is much apprechiated
Thanks
I appreciate that your plug for NordVPN didn't play into the "it makes your data more secure!" nonsense, but focused on the benefit of being able to access other regions' streaming materials. Cool cars by the way 🙂
Could you avoid the need for a sieve mesh by using a cyclone?
Doubt a cyclone would work , but with a bit of trickery you might accomplish the effect.
Since power and efficiency of the fan aren't major concerns, baffle the suction such that it's spread among multiple points, and the suction is parallel to the bottom of the car. With no direct upwards suction, it would be hard to lift anything off the ground. You could also make the inlets small enough slits that you aren't worried about anything big enough to cause damage passing through them, say 3mm openings or something like that?
An eductor type system like the Dyson "bladeless" fans would work great in this regard.
The dyson bladeless just has the fan in the bottom of the device. They want to maximize surface area, and reduce pressure.
I love how you demonstrate these scientific theories and calculations in real life experiments!
The Fan Blades rotating backwards is bothering me alot lol.. would decrease atleast 30% of its efficiency..
Dude, I am HARDCORE jealous of that classic mini! SO COOL!!! Those old minis are super hard to find here in the US.
The EDFs are the wrong way round. They are much more efficient when driven in the right direction. And maybe a blower style would be better for this purpose because EDFs have such low static pressure.
He said in another comment that this was intentional because he didn't need much force anyway
@@brrrrrr But it would draw much less power at the same thrust.
Very cool- I think the biggest short-term gains would be fixing the skirts up. You're already printing it, so some printed sliding skirts with small flat springs could work well. This would make it a lot more versatile
Suspension is another one- maybe stiffen it up a bit so you don't have so much travel for the skirt to contend with
The ultimate solution is mounting the vacuum plate unsprung. This needs to be able to flex with suspension travel, and still have a bit of movement to cope with imperfect surfaces, but takes the soft suspension out of the equation entirely.
If ytou wanted to take it to the extreme something like a 1/12 pan car could be ideal. They're already very low, have lots of surface area, and nearly locked out suspension
It seems like the past of formula 1 was a big list of trying things, new modes, projects, concepts and thank you to this videos everybody can watch that, and learn, thank you Guys!! 👍
Amaizing project! We really like it! 🤩
I have watched most of your videos but this was for first time I saw your car 4:31 ...loved it just loved it.
Multiple of the 70's F1 cars used thickly set bristles as skirts. They were stiff enough to allow creating a somewhat permeable membrane, but soft enough to bend back when contacting the ground. They were probalby the best middle-ground solution between optimal downforce and creating too much downforce, increasing rolling or even drag resistance.
I recently thought of building a similar RC car! And I would never have guessed about the dust problem just by thinking about it😂Thank you for the wisdom!
Very cool little project. I'd suggest to enlarge the area of the mesh and maybe tinker with the center of suction as needed. But the biggest potential I guess is in skirts that can slide up and down to allow for proper working suspension and minimized drag from the skirts. Cheers
You should try blowing air past the hole and creating a low pressure area. This is used in garden vacuums to suck debris up into the bags. The plus of this is that your fan won’t get clogged as you are not sucking via the fan.
Maybe already commented:
I believe your downforce is being reacted on the rigid "skirts" rather than going on to the wheels to generate grip. Skirts are supposed to slide up and down so that they don't transfer vertical force (so it doesn't take it away from the wheels, grip).
Right now it looks like you do have some additional grip because you have some additional compression on the suspension but then you bottom out the "skirts" (it's really just the body of the car) and you dont get any more grip, just more drag because any additional suction goes to the skirt/body (not the wheels). This is why you found a happy medium in the fan speed. If you remove this limitation you could increase grip further.
You could try stiffer springs so more load goes to the wheels, higher "unsuctioned" ride height or inplementing and actual sliding skirt.
Awesome video, really like the experiment!
I’ve watched a fair amount of Gordon Murray videos. My takeaway is the fan in his fan cars weren’t directly sucking the car to the ground. Instead they were designed to augment aerodynamics by managing turbulent airflow and discarding it out the back. The fan in his T.33 hypercar runs at relatively low speeds to accomplish this. People assume his cars are vacuuming themselves to the tarmac but if that were true the drag this creates would make the racing cars too slow to be competitive. The fan is about managing airflow.
IDK how much time you spend reading comments from non-paying customers, but here goes!-
Adjusting the downward suction to reduce drag is folly. You’ll never find a sweet spot that way; only a disappointing compromise.
What you need to do is keep the shocks from traveling beyond the point where it’s just about to touch the ground.
This principle should help in all kinds of situations.
Good luck, (and thanks for providing videos that me AND my wife enjoy!) 😇
When I was a kid, RC cars and walkie talkies blew my mind. Now there are drones and cellphones, and I'm kinda jaded about it all.
Very, very impressive concept and project. Im glad to see our generation giving a shit about the history of F1
I've seen a few people mention this, but I want to say it again just so you hopefully see it. Right now your suction device is connected to the chassis of the car... which... there is nothing wrong with that... it works, but this relies on the suspension being the perfect height and spring rate to keep the skirt just a hair off the ground at all times to keep suction going. This is very difficult to do, and, if the solid skirt bottoms out on the floor, then you don't have the full force of the suction giving you traction, but you only have whatever the spring rate of the suspension is giving you for traction.
Instead you need to figure out how to connect the skirt to the uprights of the tires in some way. This way the suction force is directed directly to the tires of the vehicle without effecting the suspension at all. This will also mean maintaining the proper height for the skirt will be much easier as well as it won't move with the chassis of the vehicle. Once this is done, you should have maximum traction from a very good suction along with a much improved ride quality (not that that matters too much for an RC car, but still)
this is a great practical demonstration of downforce and ground effect.
You could let the fan run backwards when steering angle is close to zero in order to clear debris off the sieve. That would require either enough negative suspension travel (to not lose wheel contact when the car is pushed upwards) or a flap on the rear portion of the skirt which opens outwards but not inwards, sort of like a one-way valve... otherwise you'll get the world's most unstable ekranoplan. But if that works, it would not only clean the sieve but even act as a (very mild) booster on straights. Also you could plaster the downside of your squishy skirt with steel thumbtacks on something like that. Would reduce ground friction a lot and not compromise the seal.
in f1 they used skirts that allowed for suspension travel with ground-effect, and they also used them in the chaparral 2j which is more like what you have here. I think your experience with worse times with minimal gains came down to the fact that you do not have those skirts, and the assembly for the vacuum hitting the ground too quickly. You could fix this by lifting the vacuum assembly and adding those to allow for more travel, and possibly stiffer springs.
9:01 Servo tester: Why are we still here?Just to suffer?
One thing worth noting was the the bt46 and lotus cars only use skirts on ether side of the car to increase the vinture effect (sorry for spelling). You might be able to increase performance by making it narrow in the middle of the floor and wider at each end as well as using a rubber skirt on both sides
I enjoy these videos so much.
I’m probably like 20 years older than you, but I’m constantly learning from all these amazing experiments. I wish I had as much creativity (I’d be happy with one tenth of it!)
:)
The original fan car, the Chaparrel 2J had a moveable skirt that was attached to the lower control arms of the suspension so only the low profile tires were a variable in how high the skirt was off the tarmac. You could limit the suspension travel to this height and use some firmer tires to keep the skirts off the ground.
the ideal adjustment to this would be to have a gear which turns from like 10% to 100% to that wheel which controls the fan speed, which you would change for gears and a motor turning them with another cog. This could be controlled remotely to allow faster straight line speed and to be turned up before breaking for corners.
Sick! Been waiting for this! Have a good weekend mate :)
Love the retro F1 engine noice overlay haha! So much more speeds that way
The engineering battle between Jack Brabham and Colin Chapman is legendary. Now we need a RC Lotus Type 88 twin chassis car.
IIRC the BT46 initially had the same problem of sucking itself down to the track and rubbing, but they solved it attached the vacuum chamber to the wheel hubs instead of the chassis. That way the suspension wasn't compressed by the vacuum.
If you ever try to optimize it, you should go back to flexible skirts. Because as soon as the hard one hits the ground, it stops you from adding vertical force to the tires and therefore adding grip. A harder suspension is also an option
This Guy is Getting Professional
you might consider a circuit to tye the fan in with the turning only. or increase pressure in the trurns, and decrease it on the straightaways.
cool video, great job!
You need a Louver or a Strata cap which prevents debris from entering the fan with a pre filter tornado effect expelling the debris & dirt to the sides. They are used in aftermarket car car intake boxes for off-road vehicles. A topspin would work too. Check out Donaldson Filtering solutions. You may be able to 3D print one. They may even sell one small enough for your application. essentially they are pre filters but work with centrifugal force of air spinning like a tornado rather than a mechanical filter which can clog.
The Chaparrel 2J (1970) was the first car to do this, 8 years before the Brabham BT46 (1978). The chaparrel was banned from all formal national and international races after one season at the american can-am races where a number of drivers complained about its vastly different racing lines.
I have 3 suggestions:
- Use a "bladeless" fan (with actual blades perpendicular to the actual flow) to avoid clogging,, so to eject away whatever is on the ground into the air, gravity will do the rest (or put a meshed bag on the output if making a vacuum cleaner is your goal). You may need 2 EDFs to get the same power, tho.
- Make the downforce proportional to the speed to avoid crushing the skirts and let the tyres make their job: more force at high speed, less force at ow speed. I suspect it's an exponential function, tho, so the speed limit is at your EDF's limit.
- You could print your skirt in TPU to make it flexible and avoid permanent deformation with electrical tape and duct tape, or just sculpt rubber from a tyre. Ideally, sandwich some metal mesh from your sieve in elastic material to add some strength (like in tyres)
in a future iteration id recommend opening the front of the skirts and the back of the skirts part of the downforce comes from the air creating that low pressure zone which is easier at the front without the skirt would add less surface friction when the skirts glide across the surface
The BT46 was a total beast... and it threw any dirt it found on the road right in the face of the ones following it, too.
Super underrated channel
With enough suction to hold it upside down, it would be cool to build a track that went up walls and across the ceiling.
I love that it sounds like a f-1 car
The dirt was also the issue with the Chaparral 2J. The didn't use a mesh to filter, so they used to thro rocks behind the car. It was band for that reason.
you defenitly should lock the suspention next time
Try adding a few ball bearing beads embedded in the skirt so they keep it just slightly off the ground. This will dramatically reduce drag without having to perfectly dial in the fan speed.
Perhaps make a control loop with monitoring wheel speed and steer angle. So at low speed where you want to accelerate and not want the drag (Launch or out of a hole). And maybe have it tied in with steering, higher fan speed with higher steer angle to stick around an apex.
Maybe have some brushes around the side like from a hoover.
4:03 omg you just gave me an idea how I can make a cheap microphone metal mesh instead of buying seemingly non existing metall mesh on Amazon
thanks a lot xD
Total respect for your real car.
Nice choice!
RIP Original camera, miss ya big man, gone but not forgotten
Not only is this guy bright & sharp...but he's funnier than hell!
The Mini is the coolest thing in this video, in my opinion.
This dude could easily be chief engineer at Haas or Williams right now 👍
What do you mean the BT46B was a giant vacuum cleaner? Clearly it was for engine cooling.
Every time I see someone do this, I'm always reminded of the line follower robot competitions in Japan; the winners always use four quad props, in reverse, so it's essentially blasting air upwards and creating downforce. At least it won't be vacuum clener anymore.
You basicy made an RC hoover.
Luv it
Oh my, I love your mini cooper!
8:55 love the fact that this sounds like a mini f1 car 🤣👌🏻
if you could find a way to make a through-hole from the front to the back of the vehicle, put your fan at the back of that hole (rear end of vehicle) then open a large hole in the middle that attaches to the vacuum apparatus, I think you would have success, as that hole leading to the vacuum now has plenty of suction coming directly from the atmosphere instead of on the ground, this suction would come from the “Venturi Effect”. That being said, holy moly..nice work so far sir.
Sick project and video. So much potential when there are no rules
Use the compressed air from the vacuum to make a jet engine at the back.
I love these car aerodynamics videos 🔥
A bristle skirt (like the bristles on a vacuum attachment) might work well to give you less drag while maintaining good down force.
Hello from France 🇲🇫
You are in the good way to explore this strange set-up.
Sorry for camera but all genius encounter problems.
You probably should explore the mass position for better handling as you have lot of weight on extremety and for better habdlig you have to put the max possible in center of car. Freeing the front for turning and the rear from centrifugal force during turn.
Also possible option could be to have a rigid suction chassis and a smooth lip around it that could be scratch by road Ithout transfer the contact vertical force to car (out of damper as it's the chassis) this vertical impact will light the down force and could be the moment of loosed handling if you are on hard turn.
Way more to explore
Way more to fun
Way more to add success
👍
Extra points for the Mini!! 😃
Awesome Video. ☺️