Steering input AC & real life

Anther feather into "it's about Direct Drive steering wheels"cap, driving - and rapid sawing - starts @ 1:30

 

What’s the point of this? He’s clearly just stuffing around with no interest in going fast

 

He is not just randomly sawing the wheel all the time though, even when the car is going straight. The point is once the car goes fast enough in any sort of trajectory over uneven surface, the wheel provides strong feedback that the driver responds to and this creates the impression of "micro-corrections". And his steering work does a good impression of the famous YellowBird vid at least, probably the best AC version that I've seen.

This RL driver was just stuffing around with no intention of going fast either btw

 

By style I don't mean that you necessarily choose it, it's just how you drive. Kind of like a baseball pitcher - lots of different styles. They didn't choose their style, it's just how it evolved.

Same car, same steering rack. My vid may look like I'm using more lock because that turn (T5 at Thunderhill) is quite sharp - it's like a mini corkscrew. Wide angle of gopro makes it hard to judge perspective.

 

I assume so, because response time is faster and torque is greater. I have T300. Really want an OSW but can't justify the cost.

 

God that extra mile video... why on earth he use that terrible sound mod, AC sound is pretty good by default, IMo it is very good. Also steering is so fake, just to make it slide, to flex a little bit..

@seniordingdong Really looked like different interior to me for some reason....

Perhaps you are right about the style, and that it is the way they developed. But I don't think that is the only reason.

For example that real life yellowbird video. By looking at it you can almost feel how he the tires are flexing left and right a lot under heavy stress. He usually adjusts steering while powersliding, like if he would powerslide in sections, or how he massively adjusts steering when going through karusel. Thats definitely not a style, but how you drive it fast I believe.

 

I think that if car drives like that it could be very much influenced by tire relaxation length and tire flex being unbalanced for front and rear, so front and rear would oscillate in different rates because of that when driving abruptly.

Tire relaxation length is a lag between steering input and when the tire build up the cornering force and is measured by the distance that it rolls. It is very dynamic I suppose that it depends on load, slip angle and so much more way beyond what I can understand probably. It will have less effect at higher speed, as I suppose it does not depend on speed so will happen quicker. But it will always add more play into steering I think.

Another thing is flex, and if I understand it correctly it has some kind of stretching effect for slip angle, right ? So if tire flex more under load it should be more difficult to locate the peak angle and could result in abrupt steering movements too.

For now it seems to me that having these in different rates at front and rear could make car understeer and oversteer in same turn, require extra steer to make it turn as desired, add some floaty sway feel in some situations, add some more wobble "tank slap", could make rear step up of the line under hard braking, steer a car slightly when it hits larger undulations or especially large kerbs, can make tramlining way stronger on kerbs edges.... Doesn't really affect overall performance and pace significantly, but transforms steering.

Obviously probably depends a lot on the rest of the physics. I have tried those things on XJ13 yesterday, was quite interesting, didn't know exactly what I was doing, just approximately, but knew what I want to get. XJ13 has Etype front geometry, basically a wider Etype front. I am quite happy how it works, a bit too scary on kerbs maybe. But it really makes sense to steer into a kerb when it sucks the car in, to keep it straight.

 

3rd post in a row, I am monologue guy. Whatever, I think that it is very interesting...

I have been thinking about steering in long curves.
5:05

3:40


Thats just a little bit like on gravel with these old cars, well in superperformance case "old". I think I have heard someone in some interview or video saying that riding on crossply tires reminds riding on gravel a bit.

I have learned about interesting thing yesterday. It is that dirt tire will benefit from less deformability, I suppose loose surfaces deformations does part of that job, plus they digs in better then. However, rolling resistance on soft surface increases with stiffer tire.

Really nice comparison. From it looks like tarmac tire has more flex than dirt tire. Tarmac tire is designed to soak more stress as surface is not deformable ?

 

I have lots of fun with this thread as you might have noticed.



Nice piece to the puzzle.

 

Interesting moment at 1:35

 

Looking like simracer randomly shaking the wheel. Notice how RL driver is sawing more/less turn to the left to catch and then to steer, and simracer is doing left/right quick steering, maybe not necessary.

But maybe I am wrong.

 

That’s cool to see. Accurate track and accurate physics so the same event in both real and virtual gives the same result. Sure you could hyperanalise how and how much each person reacted but that’s down to the different people.

 

@Andy-R does this steering movement seems realistic? It is in my book.

 

I can't watch your video on my ancient phone but yes the Cobra moves around a lot and requires more steering input than most cars, a bit like the 250F. When I made the thread the GT40 was in the forefront of my mind. Yes even that you can drive it around wiggling the wheel like crazy but it doesn't seem necessary to input much steering at all, much less than I thought it would. Some of the older cars don't feel modern car direct like the 911, 250F, Cobra post tyre wall update, 935 and maybe a few more.

 

XJ13 supports sawing steering style

Sawing feels natural, because at the limit tires are slightly less reactive, best slip angles are less obvious, front and rear tires slip in slightly different timing. This gives rather logical sense to steer wheel multiple times (through parrticular curve for example) in order to obtain or maintain optimal steer input at all times.

Car also supports regular more direct more calm steering style, but with it I am ~1percent slower, and less excited

Anyway...

Whatever. Rules broken, idk if this is correct, I am biased of course.... but I am quite sure it is something.

 

Not really its the other way around, you need more input in 918 than AC. Thats why I got the 918 Fanatech, but later found out the fanatech rim is actually a toy instead of the actual 918 steering wheel. Smaller rim mean you use even less input.

But in game, I prefer smaller steering rotation because using real car rotation doesn't give me any extra driving reward. It only made the experience less involving.​

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Edited in a way that gives a better idea how unforgiving it is.

 

Thanks, on real life trackdays/drifting , people will find out a steeringwheel never is really without motion, not even on the straights.

Cheers
Robin

 

Because AC's road bump does not disturb the movement of the car.

 

another new comparison video from Blancpain GT Driver Romain Monti where you can see the slight differences in wheel movement.

driving part starts at 4:42
I don't speak french, so maybe someone could translate, what he says in the first part of the video