2014 F1 explained: What is brake by wire? | Hacker News Reader

2014 F1 explained: What is brake by wire?

racecar-engineering.com

48 pointsdmmalam53 comments

With the endless and quite arbitrary rules and limitations they impose on the F1 cars each year I sometimes wonder what would happen if they hadn't done that. What would the teams have built if it weren't for the weigh, power, and technology limitations shaping the development?

I see an analogy to evolution versus controlled genetic reproduction: what would the F1 cars look like and how would they behave if the only thing that mattered was being the fastest and winning races?

Red Bull made a very interesting concept car a few years ago along that line of thought.

http://en.wikipedia.org/wiki/Red_Bull_X2010

It would be difficult to ensure the safety of participants and spectators if there was entirely free regulations. Don't underestimate quite how fast a Formula 1 car is now, even within the current regulations.

Formula 1 has made significant contributions to the safety of motorsports over the last two decades and much of this is due to the continual improvement and unequivocal dedication to preventing accidents. If you've never seen Kubica's accident from 2007 in Canada, it's amongst the best demonstrations of how safety has advanced in F1 (note Kubica was released from hospital the next day, unhurt). (see https://www.youtube.com/watch?v=eP1_POQPJVw)

Agreed. Kubica hit that concrete barrier at 300KM/h at a 75 degree angle, and was subject to a peak g-force of 75G. He emerged with just a light concussion and a sprained ankle. [1]

At the time, I wasn't even aware that humans could survive peak G's that high.

[1] http://en.wikipedia.org/wiki/Robert_Kubica#2007

One team would very likey dominate, and then all the other teams would quit. After all, these teams are backed by shareholders which continuously question the ROI of participating in the sport.

If you gave an F1 team their same budget with no restrictions, you would get an incomprehensibly fast car. I'd bet on them going with 6 wheels: 4 in front, two in back for more traction when turning and braking, similar to the Tyrrell P34.[1] They'd likely use ground effect with fans to provide active downforce, similar to the Brabham BT46B.[2] It would probably be driven by electric motors in each wheel. The power source would be a gas turbine attached to a generator.

It would be a death trap. If the suction fan malfunctioned, all downforce would be lost and the car would skid off the track. G forces when accelerating, braking, and turning would quickly injure even the toughest human being. Going around any track would require superhuman reaction times. Such a vehicle could only be controlled by a computer. Also, such a vehicle could only be painted plaid.

I'm not sure how profitable or safe this hypothetical series would be, but I'd certainly watch the first couple of races. Then again, I'd also watch cyborg kickboxing in some future version of the Paralympics.

1. https://en.wikipedia.org/wiki/Tyrrell_P34

2. https://en.wikipedia.org/wiki/Brabham_BT46#Brabham_BT46B.C2....

You would probably end up with something like the Red Bull X2010.

https://en.wikipedia.org/wiki/Red_Bull_X2010

The digital creation was a response to Kazunori Yamauchi's question: "If you built the fastest racing car on land, one that throws aside all rules and regulations, what would that car look like, how would it perform, and how would it feel to drive?"

> "If you built the fastest racing car on land, one that throws aside all rules and regulations, what would that car look like, how would it perform, and how would it feel to drive?"

The big question is whether it would qualify as a "car".

Get rid of the human pilot - get the engineering teams compete with fully autonomous cars, maybe with the team feeding it strategic directives during the race. I would certainly love reading about it, though I acknowledge that the lack of human drama would make poor advertising copy...

You'd quickly see how many people watch F1 because of the secret wish that something goes wrong and there is a huge crash. If there were no risks in the race, there would be no tension that keeps people from getting bored by watching cars go in circles.

You might end up with the equivalent of Group B rally cars from the 80s: Too powerful, too dangerous, and too awesome!

http://youtu.be/0fskgShipUY

Yes i was thinking about the Group B cars too.

they would probably have AI drivers by now :)

Hmm, why not simply always use the recovery system but just not store the energy in the battery if it's full already (or capacity reached or whatever)?

where do you suggest this energy should go? it's not like there's room for a bird burner on an f1 car.

Why not power up some tesla coil on the rear of the car that produces cool electric arcs all over the track.

Lets face it, some of the coolest parts of high power cars are dispersed excess energy, glowing brake discs or flaming exhausts and of course screaming engines.

yeah, that's the point. the brakes are smoking hot, so if you suddenly start to collect that energy it needs to go somewhere.

I think you missed the question/point: traditional brakes work by converting kinetic energy to thermal energy and dissipating it. The ERS base is to convert it to electric and store that.

ERS obviously can't store things when the battery is full, but if the issue here is the transition between ERS and traditional why not have ERS bypass the battery when it's full and dump energy in a radiator, ending up with the same result as traditional brakes (kinetic -> thermal) without having to switch braking system in the midst of braking?

I think you missed the first answer. There is no place for it. It's big, heavy and needs to be exposed.

Loud speakers and an amplifier to make the cars sound better?

There's presumably no more energy being dispersed than with manual brakes. The current brakes will heat less (due to energy in the ERS).

If the ERS is full, you either switch over to dumping the heat into the brakes (no ERS, switching problems), or you start to drain the ERS to make room (no switching problems). Draining the ERS will give you the same thermal problem you have with no ERS, except you have the choice of not dumping it into the brake pads - you can have seperate external resistor coils, glowing and radiating.

I really wonder how this works. Is this some generator held by the rear brakes ? How do they enable/disable this generating system when braking to go back to normal braking ?

And why the hell did they set a maximum amount of recoverable energy ? Seems like a additional, unnecessary puzzle that seems to make things harder for pilots...

>> "And why the hell did they set a maximum amount of recoverable energy"

One reason is that the energy is used for KERS, a boost system (press a button for increased speed). Each driver is limited to a certain amount of this boost per lap.

It's also possibly for safety reasons. Before a car pits or anyone can safely touch it all recovered energy must be discharged. If the car is in an accident and this isn't possible the less energy stored in the car the better.

Note that the "boost button" disappeared in 2014 [1]. (K)ERS usage is not controlled by the driver anymore [2]:

[1] http://www.bbc.com/sport/0/formula1/25158104

[2] http://www.formula1.com/inside_f1/understanding_the_sport/87...

There is no button this year. Also, batteries are heavy , where should they store all that energy if they recover all the time ?

Yeah, the Energy Recover System is essentially an electric generator hooked to a battery. It also functions as the electric motor to put the energy from the battery back into the rear wheels, for a small burst of speed allowed every lap.

I can't find a source for how it is physically hooked up to the rear wheels, but I would guess that it's simply a clutch.

Last year it was a feed off the gearbox IIRC.

I tentatively assume that allowing the cars to recover an unlimited amount of energy from rear braking would make turning too easy and/or speeds too high. The rules of F1 are mainly designed to prevent those two things.

i'd wager it's 100% a cost issue, the same reason that engines are 1.6 l, ECU is standard, etc.

It is categorically not a cost issue.

The new 1.6l V6 are more expensive than the previous generation of 2.4l V8's (which were homologated for 10 years).

Formula 1 is a sport as well as a technology industry and the regulations are constructed for many different reasons - competitiveness, safety, cost, feasability etc.

FYI, the 1.6l (turbo) engine was introduced to increase relevance to road cars, not to reduce costs.

i see this as a way to offset the cost of developing a race car engine by reusing tech in civilian cars.

That isn't the case.

I think it has a lot to do with the battery size. Last year there was I think 6 seconds of boost per lap allowed. Now it is something like 30-40 but they did need a bigger battery to support that.

I'm envisioning a lightning rod at various stages along the track to discharge the extra energy... :)

I'm amused that F1 cars now have a computer mimic manual brakes. It seems schizophrenic to allow advanced technology such as kinetic energy recovery, but ban traction control, active aerodynamics, anti-lock brakes, and dozens of other technologies that are in consumer vehicles. The excuse I typically hear is that these restrictions make races depend more on driver skill instead of team budgets. Do people not realize that the teams with the biggest budgets are the ones who can afford the most talented drivers? And it shows: The teams with the most money are the ones that consistently win.

I think F1 would be much more exciting if they tweaked the aerodynamics and vehicle size to allow more passing. If race excitement can be boiled down to one metric, it's passing. If you've seen a MotoGP race, you'll probably concur.

Life is often not quite as simple as that!

There are various other reasons for why it is easier to overtake on a motorbike in MotoGP compared to F1. There has been many introductions to ease overtaking in F1 recently - DRS, KERs (now ERS), tyre compounds etc.

There is even a working group within the FIA dedicated to exactly this, one of it's most famous studies is the CDG wing (see http://www.f1technical.net/articles/4577) - which ultimately was not adopted.

Thanks for the link on the CDG wing - I did not know that. Any ideas why it was not given a go? It seems vastly more in the spirit of racing than the 'push to pass' DRS that has not been exactly popular with the dedicated fan. I don't think the Pirelli tyres have been that popular with fans either. The CDG wing appears a lot more true to the spirit of what racing is about.

I think it was ultimately concluded that it wouldn't work in practice as well as the preliminary CFD results suggested. It was an interesting study none the less.

it is partly thanks to no traction control that we are seeing so many cars overtaking in corners. with traction control, it would be much tougher

Recent F1 championships have been extremely competitive, with several teams in the running for the title. Red Bull have been dominant, but that's not solely down to budget - they have for several years run an almost perfect campaign, down to the last detail. The best driver can't win the world championship without the best team director and the best technical director. Red Bull's success owes as much to Adrian Newey and Christian Horner as it does to Sebastian Vettel. Brawn GP won the 2009 championships without a title sponsor, largely due to the inspired work of Ross Brawn in developing the double diffuser concept.

The F1 rulebook is a complex political compromise that needs to satisfy several parties with competing interests. Bernie wants the most profitable show, the FIA want a sport that best reflects the pinnacle of motorsport and the teams want whatever they think will serve to their advantage. That balance of power is fragile and constantly shifting. The Strategy Group and the Commission have agreed to a budget cap for 2015, which should put most of the grid on equal financial terms.

There is no simple answer to the management of Formula 1, nor any magic bullet to 'fix' the perceived failings of the sport. For every fan that just wants to see a fair fight between the drivers, there is another who wants to see a pure technical competition. For every fan who wants more overtaking and a better show, there is another that hates the contrivances of DRS, tiny rear wings and the dreaded Pirelli tyres. F1 is a sport that reflects all of the complexities and tensions of finance and politics, for better and for worse. It is the biggest, brashest, richest, maddest show on earth, for better and for worse. Try too hard to constrain those forces and you end up with something like A1GP - a sport that in theory panders to the fans, but in doing so loses the magic that makes people care about this gloriously absurd waste of resources that we call motorsport.

Rougly speaking, an electric motor acts as a generator when you turn it.

I think it is shocking that after a century of motoring this idea of energy recovery from the brakes is 'new fangled'. It should have been made mandatory back in '73. Even if lithium batteries weren't available then every car has a battery, usually of the lead acid variety, plus there are things like flywheels that can store potential energy.

Formula 1 is a sport. The game is about building the most performant machine within the constraints of the rules. There is a ton of technology that is prohibited in F1 (traction control, automatic gear shifting, ABS, etc) that has been part of road cars for decades. Rule changes tend to relax the constraints from time to time for some specific reason: such as better safety, better spectacle, or cost reduction. KERS (with its driver-controlled boost button) was introduced in 2009 mostly as an attempt to facilitate overtaking, since car aerodynamics had become so sophisticated that a car following another one would get a significant drop in downforce due to the turbulence of the car in front. On the other hand, the 2014 rules appear to have been enacted mostly to help teams lower their running costs.

I think it's time we have an F1 alternative with only unmanned cars where we aren't concerned by passenger safety and can focus on pure speed.

The competition between drivers is what makes me wake up at 4:45AM every two Sundays to watch the events live.

If I were interested in experiments about mechanical speed, I would just read research papers.

That's an intriguing thought, but I fear it would soon devolve into guided missiles ...

I'd watch that... F1 without drivers but with weapons... it'd be like a real live and super-expensive version of Mario Kart...

The intention behind the introduction of KERS and now ERS and current fuel restrictions was mostly to: a) make F1 more "green" b) make F1 a platform for development of technologies that are relevant for the road cars.

Active aero isn't one of those but ERS and fuel consumption are and you can see this stuff is making its way into the normal cars already. KERS is a gimmick maybe, but I'm happy that they're tackling the problem of fuel consumption.

But but but perpetual motion machines violate the laws of physics ... therefore we should completely dump the idea of trying to conserve energy in such ways!

That's not the point of the article.

> "the mainstream media and race commentators have struggled to explain all that well"

They're not trying to spin energy recovery as new. KERS already exists. They're trying to explain the current system, now named ERS, and its peculiar bits.

I think the more interesting part of the article is how the braking behavior changes when it goes from trying to store energy to using only the traditional brake. It never occurred to me that switching systems changes brake behavior.

True, however (in my parallel universe of ideal world), bus drivers, postal delivery drivers and every other road user should know how brake by wire works in practice. The foibles of it should be no big deal, like doing a hill start with a 'stick shift' car, something ingrained into you during a driving test.

F1 is driving at 10/10ths of the car's capability and unpredictability means you can't stay at 10/10ths - crash or go slower are your only options.

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