Driver styles/preferences

[timbo]

Drivers stab the brakes in F1 pretty much. Thats why they didn't bother.

This is not correct. Yes, the initial stab is very abrupt, but the trailing off the braking phase is there, and there are some corners where the brakes are only lightly applied.


The lower trace is brake pressure.

[PlatinumZealot]

Stab fast, take the knife out slow. (As downforce reduces)

[timbo]

Stab fast, take the knife out slow. (As downforce reduces)

Yes, far from on/off.

[raymondu999]

Drivers stab the brakes in F1 pretty much. Thats why they didn't bother.

Yes, but as timbo mentions, the brake decrease is far less so. This would be amazing to see in terms of analyzing corner entry styles.

I suspect the braking limit from Vmax is not determined by machinery, more the limits of the driver - in terms of muscle strength as well as keeping eyes in sockets, as well as how strong the brake pedal actually is. Throwing back to valencia 2010 - Mark Webber's backflip; RB said after that Mark reflexively hit the brake pedal so hard that it snapped. That Vmax "brake stab" is still "smooth" given how much downforce you have, I would reckon. But the brake decrease would be very interesting.

I know ERS regenerative braking now takes up some of the load but surely it's still a function of braking? In terms of brake pressure = regen + actual disc on caliper action? I mean; they could technically set a sort of arbitrary "ceiling" as 100% on the telemetry display. Then have everything shown as a % of it.

[timbo]

I have collected quite a lot of telemetry traces, but pretty much all of them are from the dry qualifying in ideal grip conditions. The brake application traces will be much more interesting in the rain. I remember an interview with Andrea Stella who said that he was amazed at how Alonso modulated the brake pressure going into the hairpin during the wet qualifying for the German GP in 2012. He said that Alonso acted as a human ABS.

[PlatinumZealot]

Stab fast, take the knife out slow. (As downforce reduces)

Yes, far from on/off.

I know. Was just messing around. As a Hamilton scrutinizer I get to be aware that his advantage is a deft feel on the release of the brakes.

But yes they havent bothered to show it maybe because the maximum braking that the driver can do increases with the deceleration of the car... So he might be braking with all his might at 100% at 1g and it looks like 20% on a scale that was made for 100% at 5 g's. On your graph it sorta shows the effect of that too with the lower peaks.
So the question would be what is 100% braking? Locking the wheel? Or decelerating the car? The wheels will lock depending on tyre condition as other factors.. The drivers feel must guide him to how hard he should step or hor fast he must release pressure. So i would say its complicated. It would be interesting to see how the guys who did the LMP1 graphics did it. Perhaps they used a fixed maximum scale based on prior data of the car.

[timbo]

So he might be braking with all his might at 100% at 1g and it looks like 20% on a scale that was made for 100% at 5 g's.

Not sure I follow you. At 1g the limiting braking pressure will be lower than at 5g, and so would be the brake input.

So the question would be what is 100% braking? Locking the wheel? Or decelerating the car? The wheels will lock depending on tyre condition as other factors.. The drivers feel must guide him to how hard he should step or hor fast he must release pressure. So i would say its complicated. It would be interesting to see how the guys who did the LMP1 graphics did it. Perhaps they used a fixed maximum scale based on prior data of the car.

As many examples show (LMP, GT, IndyCar) it CAN be done. As I said, it should not be perfect. For example, let it be 100 kg force on the pedal. Some drivers will exceed that at some point, but only for very brief periods of time, so no big deal. It would be still miles better than ON/OFF thing we have now. You know, I kinda know where and when drivers hit the brakes most of the time...

[PlatinumZealot]

OK.. I am not afraid to admit, my assumption of increased braking with G force may be wrong in some sense, as the driver's leg as you rightly say, even if he slips from his seat a little, still has to support whatever maximum muscular load plus skeletal loads that arise. My assumption was that the muscular strength of say 100kg could be inceased upon via the leg bones if the driver allows himself to slip out the seat and put his body weight on the brake pedal... I am not a racing driver, just an armchair specialist of course. hehe.

Let's see..

In the same video he did according to the graphic, some 100% braking past a threshold of about 2.0g, but he brakes up to as much as 2.8g.

Let us assume that aerodynamic braking accounts for 1g, and the brakes are responsible for about 1.8g.

In that case, yes you are correct... Likely there is only one maximum braking value, that proportionally corresponds to the brake line pressure, and thus leg force. AND that the driver only applies the appropriate leg force as needed, based upon the deceleration that he desires. Common sense.. I guess I was over-complicating things too much Initially...

With that said... yes.. Formula 1 likely can use the maximum pressure from the teams and set that as the max scale for the graphic... Maybe they are just too cheap or couldn't be bothered.

[timbo]

In that case, yes you are correct... Likely there is only one maximum braking value, that proportionally corresponds to the brake line pressure, and thus leg force. AND that the driver only applies the appropriate leg force as needed, based upon the deceleration that he desires. Common sense.. I guess I was over-complicating things too much Initially...

No, I don't think there is a "maximum" braking force. There is a break pressure limit related to the stiffness of the brake assembly itself, but drivers are probably not reaching it, other than in some freak accidents. There is probably an "average" maximum for any driver, which will cover, say, 95% of their braking inputs, but there are also outliers, like for example an overtake by Hamilton on Raikkonen in Monza'07, where Hamilton locked BOTH wheels on the INITIAL braking.
This value probably varies between drivers, there was an article by BREMBO on that subject. But even in that case, I believe with the help of BREMBO a threshold value which would make sense for all the drivers can be found, and there plenty examples where it works.

With that said... yes.. Formula 1 likely can use the maximum pressure from the teams and set that as the max scale for the graphic... Maybe they are just too cheap or couldn't be bothered.

Probably the latter...

[Sevach]

Hey don't crap at the Youtube algorithm, it found me this.

What you guys think?

[PlatinumZealot]

Ah yes.. the flitch throttle technique!

[raymondu999]

Ah yes.. the flitch throttle technique!

"Flitch?"

[timbo]

What you guys think?

As far as I can tell, he used much less blipping in '93 and '94.
I think it has a lot to do with the throttle response of the engines back then.
To me, the more interesting thing would be to know whether he started to left foot brake once he got the cars with paddle-shifting.

[PlatinumZealot]

Ah yes.. the flitch throttle technique!

"Flitch?"

The technique was so rapid it requires a "flick of the ankle." The word got lost in translation after that, and the Easterners called it "Flich" ....True story....

[raymondu999]

What you guys think?

As far as I can tell, he used much less blipping in '93 and '94.
I think it has a lot to do with the throttle response of the engines back then.
To me, the more interesting thing would be to know whether he started to left foot brake once he got the cars with paddle-shifting.

Someone once told me it was to keep revs high to keep turbo spooled up. But not sure if that carries any credence