Inboard brakes- worth it?

[Jolle]

And, probably more on the front wheels, but brake feels is quite important too. The more distance and axle length you put between the brake and the wheel, the more elastic is will become and the less feel/control you'll have.

All in all, the small benefits of having less sprung weight and less torsional forces on the suspension arms/wishbones outweigh the downsides in feel/control, aero and stress on the driveshafts.

[Edax]

And, probably more on the front wheels, but brake feels is quite important too. The more distance and axle length you put between the brake and the wheel, the more elastic is will become and the less feel/control you'll have.

All in all, the small benefits of having less sprung weight and less torsional forces on the suspension arms/wishbones outweigh the downsides in feel/control, aero and stress on the driveshafts.

Since the braking currently is by wire and a lot of the braking is performed by the ERS which even has a longer path via the diff i wonder whether that argument is not overvalued.

For the fronts yes, but for the rears I get the impression that most of the feeling is done by clever electronics.

Main question what is the benefit. Here I fully agree, the brake is what 1.5-2kg's? That seems hardly worth the effort on a 11kg wheel and partly lost in beefing up the driveshaft. Aero wise you eliminate the intakes at the wheel, but you have to get the cooling air volume from somewhere else.

The only thing I could think off which makes some sense (to me) is to move the suspension inside the wheel, like in the active wheels. That would eliminate some of the suspension arms and clean up the flow over the back. But I honestly have no idea what the consequences are for the ride characteristics.

[e36jon]

Greetings Edax

I have wondered about moving the suspension out into the wheels but didn't realize it had been tried before. Was there a particular car during the active suspension period that was set up this way? I have only ever seen a 'research wheel' that some agency did for road cars that had everything in the wheel. Apologies for the off-topic-ness.

Jon

[thisisatest]

Without outboard brakes, there would be no excuse for all the downforce providing elements around the brake ducts. Although they're getting rid of those, aren't they?

[roon]

Simtek concept from the early nineties. One could imagine applying inboard brakes and outboard suspension here. Aero losses to the 'brake-shaft' mitigated via the chassis extensions.

[Big Tea]

I keep thinking of Mclaren's 3rd peddle and what the modern brake by wire equivalent is and could be with an inboard system.

[Jolle]

I keep thinking of Mclaren's 3rd peddle and what the modern brake by wire equivalent is and could be with an inboard system.

A few lines of code “brake a little left rear or brake a little right rear”. Where the brakes are located in the driveshafts makes no difference.

[Big Tea]

I keep thinking of Mclaren's 3rd peddle and what the modern brake by wire equivalent is and could be with an inboard system.

A few lines of code “brake a little left rear or brake a little right rear”. Where the brakes are located in the driveshafts makes no difference.

I was thinking of hiding sensors more easily

[Jolle]

I keep thinking of Mclaren's 3rd peddle and what the modern brake by wire equivalent is and could be with an inboard system.

A few lines of code “brake a little left rear or brake a little right rear”. Where the brakes are located in the driveshafts makes no difference.

I was thinking of hiding sensors more easily

What extra sensors?

[Big Tea]

A few lines of code “brake a little left rear or brake a little right rear”. Where the brakes are located in the driveshafts makes no difference.

I was thinking of hiding sensors more easily

What extra sensors?

To control how much to 'grab' which side. Am I right in thinking all regen is done off the crank? so the turning would have to be done with relation to left and right calipers. An extra wire is less noticeable tucked in against the dif than out at the hub. Unless they bond it into the suspension arm I suppose

[Jolle]

I was thinking of hiding sensors more easily

What extra sensors?

To control how much to 'grab' which side. Am I right in thinking all regen is done off the crank? so the turning would have to be done with relation to left and right calipers. An extra wire is less noticeable tucked in against the dif than out at the hub. Unless they bond it into the suspension arm I suppose

You won’t need them. They have torque sensors on the axels, wheel speed sensors, brake temperature and pressure sensors plus the brakes are electronically controlled. Next to that everything around the steering is monitored and the diff is quite smart. If they want to, it would really be just a few lines of code to have brake vector steering.

[Tim.Wright]

Brake torque vectoring is already implemented on a number of road cars. They don't need extra sensors - the 'bite' that you refer to is measured by the change in yawrate and lateral acceleration.

I don't think it's allowed in F1 though. Hiding it is very difficult these days as the standard ECU is open to the FIA.

[Zynerji]

Brake torque vectoring is already implemented on a number of road cars. They don't need extra sensors - the 'bite' that you refer to is measured by the change in yawrate and lateral acceleration.

I don't think it's allowed in F1 though. Hiding it is very difficult these days as the standard ECU is open to the FIA.

I would still expect the software to be far more difficult to police than the hardware. By making small changes based upon the state of other variables, it would be nearly impossible to know exactly what the teams were doing, or more importantly what the outcome of those changes would have on the hardware that they are controlling.

[Tim.Wright]

Software is far from impossible to to audit - and it's even easier in the F1 case where everbody run the standard ecu. The FIA undoubtedly will have the possibility to trace contol code at a level not available to the teams in order to catch out 'malicious code' for want of a better word.

In theory, and I don't know if they do this, but you could sidestep the need to trawl through source code by simply taking an SECU and subjecting to some test inputs to see how the outputs connected to the engine and bbw react on a hardware in the loop test bench.

Anyway, regarding the brake system, I don't think there is the possibility to brake differentially left to right in F1 today. The ERS which creates the braking effect is connected to the crankshaft so the left right biasing is done by the differential. You can't recreate true torque vectoring like that but you can use the coasting differential locking characteristics to much greater effect than if the brakes were purely mechanical.

[gambler]

Problems with heatsink into the transaxle?...inboards work well on Sprints because the torque tube helps eliminate chassis wrap up with soft lanky set ups,... they do use an outboard caliper at times on the rr for "control" braking on entry.