Formula 1 Losing Weight

[Tim.Wright]

Carbon wheels which have been homologated for street use have been available already for some years now .

Like any new technology, it will take some time for it to filter down from production cars to F1.

[Vortex347]

Shouldn't it be the other way round?
Aren't formula 1's supposed to be the pinnacle of automotive engineering? How come they're not using the latest and greatest?

[Tim.Wright]

Because its not commercially sustainable.

[Jersey Tom]

Shouldn't it be the other way round?
Aren't formula 1's supposed to be the pinnacle of automotive engineering? How come they're not using the latest and greatest?

It's rarely if ever the other way around. F1 is just the top level of open wheel racing, has nothing necessarily to do with pinnacle of automotive engineering.

For one, there's not much money in F1 - in the grand scheme of things. R&D budget of a big team is what, tens of millions of dollars? Hundred million? Automotive OEM's (Ford, GM, VW...) spend 5-15 billion dollars on R&D. There's just way more money, people, and time in the consumer market. Racing on the whole is a drop in the bucket by comparison. Not to take anything away from sharp engineers in racing - it's just not the same scope of resources.

Beyond that, rules and regulations severely restrict open innovation.

[Vortex347]

True but a f1 R&D budget has a limiting factor (that being the regulations) where as car manufacturers can go to their heart's content. Also I think you'll find it was a small hypercar company called Koenigsegg that first made carbon fiber wheels here be the link: https://www.youtube.com/watch?v=PGGiuaQwcd8
and i doubt they had the huge multi-billion dollar budget you speak of but regardless let's not stray from the topic!
I'm curious to hear some of your ideas for lightening cars (none have been seen yet on this thread) read my previous post for more info!

cheers!

[mrluke]

Making the cars smaller would make them lighter.

[turbof1]

That statement is incorrect. Heavier cars do not absorb forces they create a bigger one to stop! Use the good ol physics formula f = ma. a heavier car has more mass so it creates a bigger force which means it is harder to stop! Why do you think a truck takes longer to pull up then a car does!
So really your adding weight in the form of absorbing masses to absorb the forces a car is subjected to when it hits a wall. But in doing that your increasing the force a car is subjected to in a crash because Force = mass * acceleration. Why don't you just remove the absorbing mass structures, this will make the car lighter and it will hit the wall with less force (a bearable amount for the strength of carbon fiber), so you don't need absorbing structures.

I think you misinterpreted my statement.
Let's first talk about why these absorbing structures are there and why they are so important to keep a driver alive during a crash. Let's go from a chassis without these structures: a very stiff structure which indeed is lighter. However, when it hits a wall, almost every bit of kynetic energy will be transferred to the driver's body (the so called G forces, or jut force going from the formula), just because the structure is that stiff it actually stays intact and the whole deal deaccelerates way too fast. I even like to take the example of Jules Bianchi in here (RIP, Jules), who suffered his severe brain damage due the instant deacceleration. This was caused by the fact the car was hit in a position with no crash structure.

However, with a crash structure you dissipate the force through lowering the deacceleration. these structures literally turn to dust and by that it reduces the deacceleration in a very controlled way. For instance let's take your formula:
F(1)=Ma(1)*A(1) --> let's take this for a car which has no crash structures.
F(2)=Ma(2)*A(2) --> Let's take this for a car which has crash structures.

Suppose the structures add 100kg on top of original 500kg car, but reduce the deacceleration from 10m/s² to 5m/s². This might sound illlogical since with you see is a car almost coming to a stop instantly in both cases. However what actually is happening is that the nose is vaporized and moving forward, again in a controlled way. Halving the deacceleration is actually an underestimation.
So:
F(1)=500kg*10m/s²=5000
F(2)=600kg*5m/s²=3000

In this instance the added weight made the structure safer, and I did not broke physics in any way. The mistake you made is assuming that mass is just mass, while the type of mass has a direct impact on acceleration.

[Edax]

I think you misinterpreted my statement.
Let's first talk about why these absorbing structures are there and why they are so important to keep a driver alive during a crash. Let's go from a chassis without these structures: a very stiff structure which indeed is lighter. However, when it hits a wall, almost every bit of kynetic energy will be transferred to the driver's body (the so called G forces, or jut force going from the formula), just because the structure is that stiff it actually stays intact and the whole deal deaccelerates way too fast. I even like to take the example of Jules Bianchi in here (RIP, Jules), who suffered his severe brain damage due the instant deacceleration. This was caused by the fact the car was hit in a position with no crash structure.

However, with a crash structure you dissipate the force through lowering the deacceleration. these structures literally turn to dust and by that it reduces the deacceleration in a very controlled way. For instance let's take your formula:
F(1)=Ma(1)*A(1) --> let's take this for a car which has no crash structures.
F(2)=Ma(2)*A(2) --> Let's take this for a car which has crash structures.

Suppose the structures add 100kg on top of original 500kg car, but reduce the deacceleration from 10m/s² to 5m/s². This might sound illlogical since with you see is a car almost coming to a stop instantly in both cases. However what actually is happening is that the nose is vaporized and moving forward, again in a controlled way. Halving the deacceleration is actually an underestimation.
So:
F(1)=500kg*10m/s²=5000
F(2)=600kg*5m/s²=3000

In this instance the added weight made the structure safer, and I did not broke physics in any way. The mistake you made is assuming that mass is just mass, while the type of mass has a direct impact on acceleration.

Key to surviving is indeed the acceleration rate. Lowering the acceleration rate is done by progressive failing structures usually conical in shape like the nose or the side impact cones. But I think in this discussion there is one dimension missing.

Maintaining a steady deceleration rate becomes easier if the kinetic energy is reduced. The way that can be done is by shedding weight. The best design is thus a very light survival cell with some decelerating structures where all the other mass is loosely connected.

a good example is the crash of Legge at RA.
https://www.youtube.com/watch?v=ZCI-QSt0hpE

When I watched this the commentator said that the car was doing its job by dissipating energy, but in fact while spectacular only a limited amount of energy is dissipated in breaking a few bolts and pieces of CF. Most of the energy is contained in the engine and transmission hurdling trough the sky. Since this is unconnected to the driver it does not matter anymore.

I think one of the aspects in F1 is that it has no system for the engine to dive under the monocoque like they have in road cars. So in the case of a head on crash the engine is loading the nose. But for other components like the FW or wheels, the weight has not impact. For instance the weight that Mercedes is using in the front wing does not add to the system in case of a crash. That may even be true for structures that you don't see like radiators. Even if they are contained by the sidepod, if they dislodge during the impact their effect on initial acceleration will be nil.

Bottom line. If you have a survival cell of 150kg it does not matter whether the rest of the car is 500kg or 1000 kg. If it breaks off at first impact it does not contribute to the survival rate of the driver. So it is very dodgy to lay a relation between car weight and safety.

[Vortex347]

Hi guys!

I even like to take the example of Jules Bianchi in here (RIP, Jules), who suffered his severe brain damage due the instant deacceleration. This was caused by the fact the car was hit in a position with no crash structure.

I don't think this is what actually happened.... if you watch a backshot video link here:
https://www.youtube.com/watch?v=4-g5Smc0DfM
-specifically at about 24 seconds
I think you'll find his head hit the back of the loader actually
here is a picture


REMEMBER THERE is nothing in line (at the same height) as the drivers head in front of them
extreme deceleration - I don't know so much - "The report found that Bianchi's car hit the tractor at 126kph "- then it kept going after it hit the tractor. Not really a high speed accident for formula 1 and this would've been tested in crash testing.

Suppose the structures add 100kg on top of original 500kg car, but reduce the deacceleration from 10m/s² to 5m/s². This might sound illlogical since with you see is a car almost coming to a stop instantly in both cases. However what actually is happening is that the nose is vaporized and moving forward, again in a controlled way. Halving the deacceleration is actually an underestimation.
So:
F(1)=500kg*10m/s²=5000
F(2)=600kg*5m/s²=3000

You're not considering very many variables here! Sandpits are generally present on all high speed corners and a lighter car will not have as much momentum. p = mv or momentum = mass*velocity
That means the sandpits will have a bigger deceleration effect on the lighter car before it even hits the wall. Also

However what actually is happening is that the nose is vaporized and moving forward, again in a controlled way.

???
This is because the nose is made from carbon fiber. Furthermore, this has always happened to the front of the car since carbon fiber was first used in the f1 cars in the early eighties (benefit of constructing the car from that material really).

Bottom line. If you have a survival cell of 150kg it does not matter whether the rest of the car is 500kg or 1000 kg. If it breaks off at first impact it does not contribute to the survival rate of the driver. So it is very dodgy to lay a relation between car weight and safety.

The cars are designed to fall apart anyways without all this added weight.... This has been in effect since the 80's and is the reason why the body of the car is made from a larger number of pieces.

Cheers Guys and thanks in advance

[turbof1]

This is because the nose is made from carbon fiber. Furthermore, this has always happened to the front of the car since carbon fiber was first used in the f1 cars in the early eighties (benefit of constructing the car from that material really).

Little to do with that. When carbon fibre chassis were introduced by mclaren, there was indeed this fear. It however turned out you could manipulate the layering. For instance the survivall cell will stay intact to keep the driver safe from any objects penetrating it. And no, the vaporizing at the front during the crash has not always happened. Only since a front crash structure has been introduced.

Just to get momentarily further into that topic: we currently see a trend where tracks move away from sand/gravel traps. It's actually safer to have tarmac since the driver remains in control and can use the brakes, which is much better way to deaccelerate. A gravel/sand trap means you are passenger for the ride.

The cars are designed to fall apart anyways without all this added weight.... This has been in effect since the 80's and is the reason why the body of the car is made from a larger number of pieces.

No Edax is right. A F1 engine for instance will remain attached to the chassis since it's a stressed member of the car, even during a crash. Whatever that falls off is not out of safety, but to safe weight to reinforce it. With the exception of the crash structures of course, which has sideway tests it doesn't fall off (which was a very valid point from Edax, because if it does fall off it will not have an impact anymore on the survival rate).

You're not considering very many variables here! Sandpits are generally present on all high speed corners and a lighter car will not have as much momentum. p = mv or momentum = mass*velocity

A sandpit will limit the impact in both cases. I don't know you want to bring this is into the equation since this has nothing to do with the structure of a car. Whether you have 5000vs3000 force or 2500vs1500 force. I don't know why you include those variables since they they simple do not matter in the debate of crash structures vs no crash structures. A crash structure will in the end of the day be extra weight since it has mass, but makes the car much safer. Don't ask me, just compare crashes from earlier era's vs nowadays. Also, do know that a lighter car with the same horsepower will have a higher speed, so a higher velocity.

I think you'll find his head hit the back of the loader actually

I disagree, but I don't want to drag that part of the discussion any further out of respect for Jules.

For the record, I do agree with the notion that for instance a lighter crash survival cell or even a lighter crash structure, while keeping the same deacceleration rate as a heavier one, makes a car safer. However outright removing crash structures, as you proposed earlier, will only make the car much more dangerous. You are not going to reduce the mass enough to justify the rise in deacceleration.

@Edax: Do note that while a car shedding mass during a crash is generally, not always due the open cockpit, safer for the driver, it is not for others in close proximity of the car. A sharp piece of carbon fibre being flung into a grandstand would be a nightmare. It's this very same reason why tyres have to remain attached to the monocoque through tetters. It'll still dissipate quite a bit of energy in the tyres since they can still bounce, twist and rotate around, but they remain attached to the survival cell. Together with the engine, which is a stressed member of the car. It's comes with quite a bit of irony in this debate since the engine is part of the chassis solely to safe overall weight. If it were to detach, I think other structures would need to be reinforced first thus adding weight. Which as you explained would infact be safer since the kynetic energy from the engine would no longer play a role. Again only for the driver since nobody can predict what'll happen with the engine.

[Edax]

@Edax: Do note that while a car shedding mass during a crash is generally, not always due the open cockpit, safer for the driver, it is not for others in close proximity of the car. A sharp piece of carbon fibre being flung into a grandstand would be a nightmare. It's this very same reason why tyres have to remain attached to the monocoque through tetters. It'll still dissipate quite a bit of energy in the tyres since they can still bounce, twist and rotate around, but they remain attached to the survival cell. Together with the engine, which is a stressed member of the car. It's comes with quite a bit of irony in this debate since the engine is part of the chassis solely to safe overall weight. If it were to detach, I think other structures would need to be reinforced first thus adding weight. Which as you explained would infact be safer since the kynetic energy from the engine would no longer play a role. Again only for the driver since nobody can predict what'll happen with the engine.

So you're proposing to use the driver as a safety catch for the engine

For the tyres the story is clear they need to be contained within the chassis, because they can only externally be contained by having the cars race in a fully enclosed tunnel. They bounce and roll. Engines do not bounce that well. I have seen quite a few engine separations ant the only instance I can remember of an engine leaving the track is last year at nascar (apart from Le mans 1955)So I think you can get away with engine separation.


The other point is valid. But its not so much about weight or stress. I think mainly the quest for rigidity is conflicting with safety. In the search to make the frame as rigid as possible, the teams are strengthening the weakest points of the car, which traditionally are places like the connection of the engine to the bulkhead or suspension arms.

I think the current generation of cars is becoming less safe than the one before. It is nice that you have side impact structures, but you now see that the suspension arms are getting so incredibly strong, Since they are the things sticking out they determining the initial impact. So you get the scenes like in Barcelona testing where the car leaves lightly damaged on a flatbed and the driver severely concussed on a stretcher.

[turbof1]

So you're proposing to use the driver as a safety catch for the engine

It sounds cruel if you put it like that . No I am not proposing any of the sort.

I think we are talking about making compromises in general. Safety of the driver comes first, but it's not the only person around on a track. One extreme is to make the car is solid as possible which mostly protects spectators/marshalls/etc, but means certain death for the driver. The other extreme is to make every single piece of the car rip away, with the exception of the monocoque to ensure nothing penetrates it, which will protect the driver but provides a hazard for anybody too close.

Luckily, the compromises they can make are generally very well. I didn't stood still with the engine not bouncing around too much. We already talked about carbon fibre almost literally vaporizing and being a good material for crash structures (if properly layered of course).

You also made a very good point about the suspension arms. I hoped the FIA learns out of Alonso's accident and introduces crash tests on suspension arms too. Especially with a longer wheelbase and broader tyres in 2017.

[Tommy Cookers]

....... We already talked about carbon fibre almost literally vaporizing and being a good material for crash structures (if properly layered of course).

carbon fibre fragmenting and apparently turning to dust is showing that it has a very low fracture work
the rules require a crash structure around the driver that includes fibre with very high fracture work (eg Zylon)

[PhillipM]

You could, since we have mandatory engine mounting dimensions anyway, also have mandatory fixings designed to shear and let the engine leave the chassis I suppose - if that compromises the chassis stiffness too much, then all teams have to deal with it anyway, so it's not a disadvantage to any particular team, you'd want to run similar to the kevlar wheel tethers to the rest of the cell so it can't go far but even letting it shift sideways would help the cockpit deceleration a lot.

[Edax]

....... We already talked about carbon fibre almost literally vaporizing and being a good material for crash structures (if properly layered of course).

carbon fibre fragmenting and apparently turning to dust is showing that it has a very low fracture work
the rules require a crash structure around the driver that includes fibre with very high fracture work

What I think F1 is looking at is at high speed impact testing of nose cones etc.

Things like fiber pullout, single fiber failure, take place on a different loading/timescale.

This is pure shock loading. At very high deformation/loading rates literally anything turns into dust. Simply put the material cannot deform fast enough, and cracks cannot keep up with the deformation rate so it turns in to dust. Look for Rankine Hugoniot conditions.


OK maybe a bit extreme, but it is just so cool.