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Im having a argument at the moment with a family member about F1 braking systems. He sais that all 4 wheels are controlled independantly, thus you can see this in the lock ups etc...

But the braking systems are 2 systems, one for the front and one for the rear. And the reason for the lockups is because the inside wheel is traveling faster than the outer one going into a corner.

And one other thing is in the argument is how can a driver change the brake ballance on the run up to a corner, he thinks there just isnt enough time to do that. There is, as you can do it on a straight. Unless he is meaning at the start of the race, whitch there just isnt enough time to think.

I think you're right in both cases. I won't give you any braking systems insights, as there are other members who really know.

As for the second part take this video as an evidence:

[youtube]http://www.youtube.com/watch?v=6FecwbemIeg[/youtube]

Notice MS change the brake balance before T1 and definitely before the the left-right-left slow corners sequence at the end of S2.

Braking system has too be mechanical and can't be used for steering. That rules out independent braking on the sides. But front/rear balance can be changed as long as system is mechanical.

Getting back to ESPImperium's original question, first the locked brakes. It isn't caused by different wheel speeds. In fact, the inside wheel in a turn is always going to travel the shorter distance than an outer .. so therefore the inside is rotating slightly slower than the outside. But three things happen when braking into a corner. First, the car's aero is pressing down very hard, because logically, the car is being braked from a higher speed. But as the speed drops, so does the aero influence. So as the speed drops to a much lower value, eventually it drops so much that the wheel loses traction and we see lockup. Second influence under braking is weight shift to the front. Most of the weight is transferred to the front, which become the most loaded, and most important wheels in a braking scenario. And thirdly, as the car initiates the turn (trail braking is practiced by F1 drivers), there is a weight shift of the car towards the outside. But that means the inside wheels are not as highly loaded as the outsides.
So let's take this information and play it back under braking. As the driver presses on the brake pedal, the brakes clamp on the disks, and the car decelerates. It is being pressed firmly on the track by downforce. But the weight shifts forward, and most of the work is being done by the fronts. The car decelerates, and at some points so much downforce is lost that the brakes can overpower the traction. Additionally, as the car turns in, the inside wheels become less loaded. So the inside front wheel has less force pushing it into the track the further the driver takes the car into the corner. For an aggressive hard braker like Lewis Hamilton, this is when and where you will see him lockup the inside front wheel.
The brake balance can be easily and quickly altered by the driver. It is designed for that purpose. And yes, there is enough time for a good driver to make those adjustments underway.

Yup, everything Dave has said seems right to me.

DaveKillens wrote:The brake balance can be easily and quickly altered by the driver. It is designed for that purpose. And yes, there is enough time for a good driver to make those adjustments underway.

As Mod´s video showed you, MS was an expert doing that. He also was an expert trailbraking. And controlling traction. Well, he was an expert in almost everything!

timbo wrote:Braking system has too be mechanical and can't be used for steering. That rules out independent braking on the sides. But front/rear balance can be changed as long as system is mechanical.

And yet vehicle stability control - available on the most mundane of production cars (Toyota Camry!) - provides independent braking . . .

Yet one more area where F1's rules makers ensure that "the world's premier race cars" are technically inferior to production cars costing $20,000.

Sigh . . .

donskar wrote:And yet vehicle stability control - available on the most mundane of production cars (Toyota Camry!) - provides independent braking . . .

Yet one more area where F1's rules makers ensure that "the world's premier race cars" are technically inferior to production cars costing $20,000.

Sigh . . .

Well, in that case, and in case of traction control I think it's good. There's already some kind of autopilot (smart cruise control) that makes sure you won't jam into a car infront of you and watches roadmarks, there's integrated GPS/navigational system being developed that would check if you have too much speed going into the corner... So I think not far off are days when you would put your drunk ass into a chair mumble something like "take me home..." and silicon genius would do all the job. I DON't want that in F1

OTOH, variable valve timing, variable intake/exhaust geometry and many other technologies that are already on roadcars HAS their place in F1!