
The Search for the Extra Pedal (2017) - tzhenghao
https://www.mclaren.com/formula1/inside-the-mtc/mclaren-extra-pedal-3153421/
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Yetanfou
Anyone who has ever driven a tractor will find this article strangely
familiar. Tractors generally have two brake pedals, one for each wheel. When
driving over roads or hard surfaces those pedals are locked together to keep
the vehicle from swerving off the road due to a carelessly applied foot. Off-
road these separate brakes are used both to turn tighter corners as well as a
poor man's substitute for a differential lock - with diff lock applied the
driver has to remember not to rely on differential braking as that just wears
out the brakes without achieving anything useful.

I have a few tractors around the farm, all of them have two brake
pedals/levers. This even goes for the smallest of them all, an Irus U1200 two-
wheel tractor with an 8 hp Hatz diesel.

~~~
js2
What’s the placement? Clutch, left brake, right brake, throttle?

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bryanlarsen
Most tractors don't use a pedal for throttle, they use a hand lever. You've
seen pilots use a similar throttle control in airplanes in movies. But there
are tractors with foot throttles. We had one, the throttle was underneath the
two brakes.

The two brake pedals typically look like a single pedal that's been split in
half.

~~~
js2
> Most tractors don't use a pedal for throttle, they use a hand lever. You've
> seen pilots use a similar throttle control

Hah, how to tell a city slicker. That makes a ton of sense though. Obviously a
tractor is mostly wanting to maintain a slow but constant speed over a bumpy
terrain. Having to do that with a foot pedal would be a pain.

At least I know what a PTO is, but only because of reading how dangerous they
can be.

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handedness
Presumably due to licensing considerations, the article didn't include actual
photo Darren Heath captured at the time of Hakkinen's setup:
[https://i.imgur.com/rBJpPrX.jpg](https://i.imgur.com/rBJpPrX.jpg)

It's worth noting that the present driver-adjusted differential locking
systems they have effectively replicate much of this behavior, but without
nearly as much mid-corner control inputs from the driver. When something that
works gets banned, the teams always find another (and often better) way of
replicating the effect.

[https://www.f1technical.net/forum/viewtopic.php?t=13671](https://www.f1technical.net/forum/viewtopic.php?t=13671)

The MP4/13 (McLaren's F1 car in 1998) also tested an early version of what we
now call KERS (Kinetic Energy Recovery System):

[https://www.motorsportmagazine.com/archive/article/september...](https://www.motorsportmagazine.com/archive/article/september-2008/58/spin-
doctors)

[https://www.f1technical.net/f1db/cars/810/mclaren-
mp4-13](https://www.f1technical.net/f1db/cars/810/mclaren-mp4-13)

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mhandley
It would be great to make this legal again today. With the current fuel
restrictions, you couldn't use it a lot or you'd run out of fuel, so you'd
have to save it for when you really needed it. Anything that allows a bit more
driver-controlled variability between the cars would make for better racing.

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js2
Clever. Perhaps unappreciated is the athleticism of the drivers:

> It was more work for the drivers, but Coulthard says he adapted quickly: “It
> was a switch to choose left and right, and an additional pedal,” DC recalls.
> “Racing drivers, if they have to sing the Russian national anthem backwards
> while juggling grenades, and it gives them a tenth, they would do it! The
> competitive animal that you are, nobody would say something is too difficult
> if it gave you performance.”

I’m a decent stick shift driver and I can’t imagine dealing with four pedals.
I’m sorta surprised they didn’t do it with a pair of handbrakes, like in the
XC trial cars mentioned but maybe taking your hand off the wheel is too much
of a disadvantage in F1?

~~~
paganel
There was a time when F1 drivers were taking their hand off the wheel in order
to change gears, as this famous on-board video of Ayrton Senna at Suzuka [1]
in 1989 clearly shows. Having only one hand on the wheel while you’re taking a
turn at 270 kph is peak vintage Formula 1, it’s pure racing. Nowadays most of
that raw feel is gone.

[1] [https://youtu.be/Vj6ovrKExJE](https://youtu.be/Vj6ovrKExJE)

~~~
jskopek
Modern F1 drivers are now navigating complex multi-level menu systems on their
steering wheels with one hand while turning with the other, so I would argue
that this talent is still present and visible in a modern race. Not to take
away the incredible talent of earlier drivers, however; it’s remarkable what
they had to do back then.

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beat
That's fascinating. You don't see old-school imaginative solutions like that
in F1 anymore. Now, it's all about tiny bits of aerodynamics at great cost.

~~~
shakehar
It is the law of diminishing returns, after 1001 races they have probably
exhausted all of such simple but ingenious performance solutions. It is still
a shame shame that the other teams were able to get this banned, McLaren might
have been a different team today had they kept this competitive advantage.

~~~
jerkstate
there is still an amazing amount of intrigue around exploring the edges of F1
rules. from just the past 10 years, competitive advantages include double
diffusers, exhaust blown diffusers, F-duct, flexible front wings, split
turbocharger, tubulent jet injection, 3D printed pistons, blown wheel nuts,
microdrilled brake disc vents, Y250 vortex generators, grapefruit juice
smelling fuel, MGU-H/MGU-K tricks, and plenty of stuff that we don't know
about yet..

~~~
shakehar
True, but all these changes cost a lot of money and time.

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averros
Airplanes have differential braking (in some models there's no other way to
steer on the ground, in most the nose or tail wheel is turned by the rudder
pedals), and the brakes are controlled by pressing rudder pedals by toes
(rather than pushing them in by heels which moves rudder). This reduces the
need for pedals from 4 to 2.

Never mind that in a performance landing (such as short field) you use not
only brakes but also yoke/stick (2 degrees of freedom) for one hand and
throttle for another. The exam standard for commercial pilot is to be able to
touch down on a designated 100ft stretch of runway with centerline between
main wheels). Add to that your usual wind, turbulence, and thermals on the
approach path which make every landing different, and you'd realize that what
ground drivers do isn't very exceptional, and that one could train to get
proficient in juggling a lot more controls at once:)

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mianos
As the ERS uses motors to regenerate power and assist braking this would
probably just be a few lines of code these days. Although ABS not allowed, I
think they can use ERS for yaw control under braking (if not someone can
correct me?)

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hinkley
I thought I read that all wheel drive systems often have something like this
today. The expensive ones can control the power ratio to the outside wheels
coming from the differential, while some of the cheap ones just apply the
brakes.

This is just a manual precursor to those systems. No?

~~~
rconti
Yes, it sounds very similar.

Today, many cars -- even performance cars -- use brakes in place of a
differential. In fact, IIRC, McLaren road cars don't have mechanical
differentials at all, and they're hardly slow!

Instead of a mechanical device employing a series of clutches that only allows
x% more speed or torque or whatever to another wheel, you can (effectively)
infinitely vary the amount of power to each wheel by selectively applying
brakes. What used to be a crude/cheap traction control hack quickly became
'better' than the real-deal mechanical device.

~~~
ska
I seem to remember that was an old idea too, but primarily limited by brake
technology (cooling, probably).

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westmeal
Why not have the brakes actuated with paddles? It'd be more complex and
expensive but you wouldn't have to think about your second brake too hard and
during turn in you can just squeeze on whatever side works best for maximum
grip.

~~~
awad
If you're talking about why didn't they do it back then? Likely, they wanted
to hide it altogether and the steering wheel is more visible than the
footwell.

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village-idiot
Part of the unspoken story is that Alain Prost’s relationship with the FIA
during the 1990s was kind of shady.

