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F1 Transmission V4 v35.zip in your github was it supposed to be the same as the test prints?

With all due respect and from my ignorance, allow me to suggest a wheel that cushions this ruclips.net/video/J0sS3Z3BkJU/видео.html And because there are three wheels, I suggest you watch this video of German record-hunting cars. I love the minute autounion 3:00 ruclips.net/video/_I_8VsH01rk/видео.html and es.wikipedia.org/wiki/Autom%C3%B3viles_de_carreras_Auto_Union#/media/Archivo:Auto-Union_Typ_C_Stromlinie_front-right_Audi_Forum_Ingolstadt.jpg

At a certain speed with this design would it make sense for the rear assembly to be a semi-lifting shape the causes the rear wheel to no longer contact the ground and steer entirely via aerodynamics? The goal being to reduce steering instability introduced by ground irregularities.

As a complete layman, I have one suggestion: why not have the tail rudder pivot on the axle line, and the forward part of the pivoting rudder will also end up offsetting the wind forces the servo needs to overcome.

Beautiful work man. Much appreciation from a dude who is losing his way in a similar project. I just have a small question to ask. Looking at your self-built electromagnetic actuator, I wonder if you have ever considered a push-pull solenoid? I have tested them and they operates kinda okay.

Out of curiosity how much down force in Kg or lbs does the Hyper car create at different speeds, say at 10mph increments?

Hey! I always love seeing your videos pop up in my feed, they're always top notch! Suggestion: Have you considered "gearing" the tail-fin? Instead of using a lever arm connected to the servo, having some kind of "rack & pinion"-esque thing, which could either be integrated into the rotating section of the fin, or some kind of reduction-gear stack (xtra weight too)? Unless the servo linkage doesn't really cause any aerodynamic issues... just something I thought about. Great video as always!

"ground effect'... Utilize afan...turbine...to suck down the vehicle.... Mind the rotational forces ennacted on the moving vehicle... There'll be tendencies to pull the vehicle to 1 side. Possible solution is to have two opposed rotating element's... Now you are talking down force and drag... Get rid of that! "air foils"? Ditch them... When you have that ducted turbine/fan/ or fans...with a skirt surround the edge...think that weird plastic at ice rinks...low friction...and a simple mechanism literally using a lever.. Maybe a spring...better, 3d print a price where using material's width and different mass in specific sections to provide that spring force but no other parts are required to be added...what is the word for such parts? Designs? Compliant parts? So, when the vehicle starts to lift... Pressure is removed causing the mechanism to lower that bottom skirt...and raising it as the car squats. Trust me...ditch the wings and 'traditional' aero ideologies.... You'll have incredible results with a turbine...just don't forget that rotational force which will pull it to 1side.

my dad and i have built a few rear steer trikes, our biggest issue was getting the back wheel not to hop when turning at speed. all of them hopped the last one hopped the least but at full speed it always hopped with any steering input.

Go look at the Carbinite LSR program. I think that shape will be much better and you won't have the rear steer issues. The full scale version was involved in bad crash caused by a rear tire failure, but the testing runs showed massive promise.

Go watch this interview with Andy Green regarding the Thrust SSC program and the struggles he had with the rear steer system. It was border line undriveable. I'm not sure you can make it work for a fast RC car, especially since there is no driver feedback to feel what the car is trying to do. ruclips.net/video/Flm95WwYLgk/видео.htmlsi=xlUn7W7My1-5GvdD

Could you rotate the steering pivot axis to lessen the mechanical trail? There would be some jacking effect, but I'm curious.

Interesting stuff, I am starting out on my first stream liner, mine will be less technical design and more test and see 😂

I wonder if extending the tail fin forward of the pivot point might improve the steering at high speeds. Moving the CP forward of the pivot would cause the airflow to help turn the wheel in to the turn when the car starts to go sideways. Maybe moving the pivot point over to the wheel axel would help also. What would happen if you added down force to rhe rear wheel?

Hi Afxentis now has a record of 183mph on 4s

RC cars have suspension too !?

6 minute's in. I was looking at your three wheeled design. In my opinion, the car, looking like that, or typical land soeed designs, should want to weathervane. So, it should want to do that with the designs appearance, however any steering input whatsoever would do the opposite of what a vane would want to do. My point is, the fin should move in the opposite direction to the rear wheels steering angle to counteract the wheel. Maybe it shouldn't even move.

This design is so cool! You should add down-force on the rear wheel as well. It really is interesting to think about how much acceleration is required for this record.

Run it on a straight tether line ..

Nice project . For a fast servo actuated ....thing, you should takeinspiration from the Dynamic soaring speed machines. (548mph). In particular the servo arrangment to avoid flutter. ruclips.net/video/nv7-YM4wno8/видео.htmlsi=bsb_DIs-UFA0gtiD&t=1555

The big issue the ROSSA land speed boys have been facing are the tyres. Not so much with the areo.

Do the rules prohibit any sort of rocket power? Because you got a very short track, have you thought about active cooling? I'm thinking a CO2 cartridge in the nose blowing past all the components and out the back.

Active aerodynamics. It's not a car, it's just a wheel powered aircraft that doesn't take off. ArduPilot is your friend. Edit: I should have waited more than 10 seconds to make a comment. 😶

Okay, hear me out put the steering servo behind the steering wheel, and the servo shroud should be a tall vertical stabilizer, above the airstream of the body; putting this weight behind the wheel would give you the proper weight distribution as well as allow far better geometry for the servo. I think the vertical stabilizer is kind of a must have.

Have you ever tried to install air brakes

Weight at the front and aerodynamic drag at the back. Like a dart. Will want to go straight. You could incorporate gyro stability aerodynamic surfaces.

you could go to a 400m track for runners and test laps there. i do this and its pretty amazing because those tracks are all over the World and you can compare times,

Could making the leading and trailing edges of the wheel hubs round help reducing drag? If you need to move the center of gravity backwards, maybe use beefier steering motor, or motors, maybe even strong enough to move the mechanism into it, maybe using two servos get get the force you need if one servo that's strong enough by itself is too wide? Could tilting the steering pivot angle help with stability?

Very interesting project, keep it up !

Rear wheel steering worked amazingly well for Thrust SSC, I think its THE way to go. Only difference is driving through the front wheels as opposed to having a jet push the car which allows the front wheels to "freewheel" which does not interupt tracking in a straight line. But I still think its definitely worth pursuing.

I am not a fan of the rear steer. One way to help the sloop is like 3d rc planes do, they use two cables, one on each side in a pull/pull mode. But at 100+, any sloop is magnified. You should have a large fixed fin on the rear and the wheel steer inside (yes I know thats more drag, but its more stable), if you want a rudder, it should be small, not the whole thing moving, just way too much imo. Good luck

It was mentioned that you didn't understand rear wheel drive for a car like this. I have no idea about cars but with Rockets they need a significant part of they're mass a distance from the engine for stability. It's counter intuitive but with a long slender car it may be the similar dynamics. Also with the realm that the car is operating in you may see less drag without wheel fairings. Axel fairing to a aerodynamic optimized disk wheel at least on the front. I think maybe the rudder is all that's needed for steering and no wheel steering would be needed or decoupling the wheel from the rudder maybe a good idea. I think you touched on that in the video. Such a cool looking car. It looks fast sitting still! Basically an airplane flying against the ground.

Have you considered this same configuration, only with four wheels in front, each with it's own independent suspension, and all driven?

I 'think' that drag reduces at the square of the scale, so that's another way of saying that the aerodynamic drag of bodies is far less of a consideration at smaller scales than at full size. As you point out, the running surface is MUCH rougher in comparison than for full size cars. You're effectively hitting lumps and bumps that are 10 times the relative size, so suspension and stability over rough ground is probably more important than aero. The reason that most speed cars use 4wd not FWD is that you don't have a great deal of time to accelerate into your speed run because of radio range restrictions, and (in many cases) loss of sight of the vehicle's orientation (can't tell which way it's pointing to correct steering). Again these are not issues in full size speed cars so that's why this isn't an issue for them. Ideally you want as much grip as possible so you can get your power down fast and early.

I feel like a solid front axle on a fwd could introdruce some problems on braking

You've wasted way to much time on 3d printed bodies. 3d printings is way to heavy and brittle. Great for prototypes not great for production or finished models... better off using the print as a shell for vacuform poly carbon shell. Good luck I would love to be proven wrong.

Think looks like a sting-ray, especially with the steering oscillation...

Can you make the rod of the body flex only vertically as well? Might help with the rear suspension rate.

lock the rear, 'steer' it with torque distribution, like a skid steer (or tank, or dozer). it won't need to turn sharp, just go straight. It is much simpler to do that with two motors!

huh, neat.

For positive aerodynamic stability you want the majority of wetted (surface) area behind the CG. I think you will need a lot of nose ballast to achieve that with this design.

You could try to angle the rudder/steering axis to bring it closer to the contact patch of the tire?

Im currently building a vehicle with a single hub motor at the front and rear steering, a bit like the yellow one you showed in a previous video. I figured the CP would be too far forward in a reverse trike layout but maybe im wrong about that with the nose sticking out so far. Are you on the rossa FB group?

Bro you need tail part like shadil cork

Had the exact same idea since a long time ago, but my major is aerospace engineering and thus not much knowledge on electronic and signal processing side of things. Also have schoolwork and I'm lazy so... never implemented that into reality. Watching this and knowing someone not only have the same concept but also managed to make it work is very inspiring to me. How I wish I could have that much talent in that many different fields.

Good Work . Very interesting. I dont Know why but from my gut feel i would angle the fronwheels inward like Highspeed cabin road cycles do. Maybe you should get a little inspiration there.

You can use 2 drive motors that can steer the car without having the rear wheel steer to keep the car straight or turn. The gyroscopic forces from having 2 separate motors driving the front wheels can keep the car straight and you can use a gyro with it. I have seen a video where a person used 2 quadcopter motors as hub motors and got up to 180 mph I think with it tracking straight as an arrow.

Be careful with using the active aero as a brake, may end up “blanking out” the rudder and causing a loss of stability. Same reason a “deep stall” occurs in aircraft.

Awesome Video

Why design when you can steal? The back of your car or "tail", is acting exactly like the back of a "tail-dragger" airplane. Look at all the old planes that dragged their tails in the dirt, grass, etc. How did they solve the problems you are having? You could actually put a "skid" on the rear and some small cannards. As soon as the car moves forward, the rear comes up off the ground. No dragging, no suspension. You could even make the skid/tire "fall away" as the rear lifted.