F1technical.net

"Electronic control of the rear brake circuit is permitted in order to ensure consistent braking whilst energy is being recovered." http://www.f1technical.net/news/18526

Now that we know that eletronic control of the rear braking circuit is allowed in 2014, does anyone have a good knowledge into what this really is, and how it is supposed to work exactly? The teams must be after something already, otherwise they wouldn't have suggested it to the FIA for approval.

Braking is influenced by the carbon brake discs and by the generator that harvests the energy for the MGUK.
Both elements produce a certain torque at the rear wheel.

An electric control could mean that the rear wheels angular velocity is allowed to be measured and if the change in comparison to the front wheels/vehicle speed is to high, teams are allowed to reduce the braking torque at the rear wheels.

As teams want to recover as much energy as possible under braking, i would assume the pressure in the rear wheel brake circuit is allowed to be reduced, as we know it from road car's anti lock braking system.

Note that's only speculation and my thoughts!

Tomba wrote:"Electronic control of the rear brake circuit is permitted in order to ensure consistent braking whilst energy is being recovered." http://www.f1technical.net/news/18526

Now that we know that eletronic control of the rear braking circuit is allowed in 2014, does anyone have a good knowledge into what this really is, and how it is supposed to work exactly? The teams must be after something already, otherwise they wouldn't have suggested it to the FIA for approval.

it will allow the computer to "mix" recovery and mechanical braking to provide a consistent braking force depending on how hard the driver pushes the pedal

With out it the brake balance would be all over the place depending on how much the KERS is harvesting

langwadt wrote:

Tomba wrote:"Electronic control of the rear brake circuit is permitted in order to ensure consistent braking whilst energy is being recovered." http://www.f1technical.net/news/18526

Now that we know that eletronic control of the rear braking circuit is allowed in 2014, does anyone have a good knowledge into what this really is, and how it is supposed to work exactly? The teams must be after something already, otherwise they wouldn't have suggested it to the FIA for approval.

it will allow the computer to "mix" recovery and mechanical braking to provide a consistent braking force depending on how hard the driver pushes the pedal

With out it the brake balance would be all over the place depending on how much the KERS is harvesting

I believe you are correct.,,,As we add more and more computer will we someday soon see "active cars"?

Worky68 wrote:[...]

It is Kers harvesting under traction.

I posed this question to Peter Windsor last year, and he confirmed on his podcast that KERs harvesting was being carried out under part throttle conditions.

[...]

That was posted in the RB9 thread after the appearance of "mysterious" tire tracks in Montreal.

In any event, if it's true that KERS harvesting is taking place under part-throttle conditions, could electronic brake control next year possibly open a window for teams to create a form of traction control? Say the KERS detects a sudden spike in the amount of energy recovered under those partial-throttle conditions, such as what might occur with excessive wheel spin during acceleration, could the teams use the electronic braking system to stop it?

That was posted in the RB9 thread after the appearance of "mysterious" tire tracks in Montreal.

In any event, if it's true that KERS harvesting is taking place under part-throttle conditions, could electronic brake control next year possibly open a window for teams to create a form of traction control? Say the KERS detects a sudden spike in the amount of energy recovered under those partial-throttle conditions, such as what might occur with excessive wheel spin during acceleration, could the teams use the electronic braking system to stop it?

Yep and they might also use it to develop a demon torque vectoring diff action as well.
I doubt the FIA will be able to sort it out either.
Next year the tyre problems will be their main concern.

All this has been predictable for over 12 Months.
It is a result of the high downforce and the need to use regulations that give an illusion of competition at the expense of tyre and mechanical reliability.
In 2014 unless downforce is reduced by a large amount, the issue will become a joke.

I remember reading article that said that ABS would be allowed for 2014. So something along the same lines is indeed permitted. Wonder how that would affect racing, as all sorts of tricky things are possible with control of the brakes.

With those regulations it would be possible to create some sort of active stability system? Where the brake force on the rear wheels is independent from left to right. That could give more stabile braking. And perhaps even braking the inside wheel in turns.

Holm86 wrote:With those regulations it would be possible to create some sort of active stability system? Where the brake force on the rear wheels is independent from left to right. That could give more stabile braking. And perhaps even braking the inside wheel in turns.

I just said that.

The problem is by using such systems to give wide variations of torque output across the rear axle, the result will give the already borderline tyre construction a lot more to deal with.

autogyro wrote:Yep and they might also use it to develop a demon torque vectoring diff action as well.
I doubt the FIA will be able to sort it out either.
Next year the tyre problems will be their main concern.

All this has been predictable for over 12 Months.
It is a result of the high downforce and the need to use regulations that give an illusion of competition at the expense of tyre and mechanical reliability.
In 2014 unless downforce is reduced by a large amount, the issue will become a joke.

According to the FiA's Charlie Whiting there will be big drag and downforce cuts equivalent to 2.5 s of additional lap time. They say it is necessary to stay in the energy budget of 100 kg fuel per race.

Re the electronic rear brake system it was said that the system would be brake by wire. But it wasn't mentioned that the system will use sensory feed back which ABS would do. For me it sounds like there will be a total electronic braking system including the front brakes. How do you brake at the front hydraulically and at the rear with electronic control? That would not work. So the brake pedal is an electric actor for an hydraulic servo system. The computer uses both sources of torque according to his programming. We can only speculate what will be allowed in terms of sensory feed back. But I'm confident that it will be under the control of the FiA. They check all computer functions and the software that is used by MES. So if there is trickery that would be deemed an unsuitable driver aid the FiA would ban it.

What the system certainly would do is making the brake balance and the KERS harvesting easier for the drivers to control. They will probably have less buttons and dials to use. But is it desirable to have your drivers twist a bunch of knobs all the time? I do not think that would be an unsuitable driver aid. IMO they are ending a practise that makes no sense and give the driver back some opportunities to focus on driving. The same thing is true for the KERS boost button. It will be replaced by dual torque computer control for acceleration. The steering wheel might become a little more manageable with those changes.

WhiteBlue wrote:

autogyro wrote:Yep and they might also use it to develop a demon torque vectoring diff action as well.
I doubt the FIA will be able to sort it out either.
Next year the tyre problems will be their main concern.

All this has been predictable for over 12 Months.
It is a result of the high downforce and the need to use regulations that give an illusion of competition at the expense of tyre and mechanical reliability.
In 2014 unless downforce is reduced by a large amount, the issue will become a joke.

According to the FiA's Charlie Whiting there will be big drag and downforce cuts equivalent to 2.5 s of additional lap time. They say it is necessary to stay in the energy budget of 100 kg fuel per race.

Re the electronic rear brake system it was said that the system would be brake by wire. But it wasn't mentioned that the system will use sensory feed back which ABS would do. For me it sounds like there will be a total electronic braking system including the front brakes. How do you brake at the front hydraulically and at the rear with electronic control? That would not work. So the brake pedal is an electric actor for an hydraulic servo system. The computer uses both sources of torque according to his programming. We can only speculate what will be allowed in terms of sensory feed back. But I'm confident that it will be under the control of the FiA. They check all computer functions and the software that is used by MES. So if there is trickery that would be deemed an unsuitable driver aid the FiA would ban it.

What the system certainly would do is making the brake balance and the KERS harvesting easier for the drivers to control. They will probably have less buttons and dials to use. But is it desirable to have your drivers twist a bunch of knobs all the time? I do not think that would be an unsuitable driver aid. IMO they are ending a practise that makes no sense and give the driver back some opportunities to focus on driving. The same thing is true for the KERS boost button. It will be replaced by dual torque computer control for acceleration. The steering wheel might become a little more manageable with those changes.

I don't think it would be hydraulic fronts and electric rears. I think both front and reas would be hydraulic as of now. But the rears would have an electronic brake pressure regulator. Allowing for the ECU to reduce the mechanical brake force when there is an increase in KERS harvesting. Then you wouldn't need sensors. You just need to calculate the brake force of the ERS system and then reduce the mechanical brake force accordingly.

Holm86 wrote:I don't think it would be hydraulic fronts and electric rears. I think both front and reas would be hydraulic as of now. But the rears would have an electronic brake pressure regulator. Allowing for the ECU to reduce the mechanical brake force when there is an increase in KERS harvesting. Then you wouldn't need sensors. You just need to calculate the brake force of the ERS system and then reduce the mechanical brake force accordingly.

Such a system is possible but it would not be brake by wire. The communication on this is a bit unclear:

"Electronic control of the rear brake circuit is permitted in order to ensure consistent braking whilst energy is being recovered."

While consistent braking is already somewhat of an issue with current KERS systems, the additional capacity of the 2014 energy recovery units will extend the difficulty to ensure a consistent feel for the brakes towards the drivers. Similar things are already going on in the automotive industry where manufacturers are looking to increase the recovered energy under braking. These system are called brake-by-wire where many of the functions of brakes previously performed mechanically will be performed electronically.

Allowing electronic control in F1 will increase the complexity of the rear brake system but will also increase its road relevance, something very welcomed by the manufacturers.

You could be right and they have mentioned "brake by wire" only as a reference for the road relevance.

As we add more and more computer will we someday soon see "active cars"?

Heavens, NO! Surely the sport would never get to the point where the drivers are simply technicians, merely guiding cars that are primarily controlled by computer programs.

Oh, wait......

How much braking do the front brakes do compared to the rears now? The bias will be shifted more rear for KERS harvesting I'm' guessing.

This electronic system will try to keep the rear braking the same no matter how much KERS harvesting is going on. Brake pedal position will call for a certain negative torque and the computer will figure out how it wants to achieve that between the KERS and hydraulic actuators. I would not be surprised if this will have to be mapped and submitted just like the throttle position vs power unit torque demand.

dren wrote:How much braking do the front brakes do compared to the rears now? The bias will be shifted more rear for KERS harvesting I'm' guessing.

This electronic system will try to keep the rear braking the same no matter how much KERS harvesting is going on. Brake pedal position will call for a certain negative torque and the computer will figure out how it wants to achieve that between the KERS and hydraulic actuators. I would not be surprised if this will have to be mapped and submitted just like the throttle position vs power unit torque demand.

Hmmm, it would be far better to use a combined energy recovery unit/gearbox than to continue struggling to deal with having the ERS-K on the front of the engine where it can only recover energy through the engine.
Seems logical to me