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.
Not unlike a motorcycle either where at least the older ones had separate controls for front and rear brakes. Some newer bikes have linked brakes where applying front and/or rear partially actuates the other end as well.
You can't steer with that though. The linked breaks are mostly for traction control and to stop you disturbing the chassis too much.
[edit] got called on the "can't steer" part - It still isn't your steering, but it changes the chassis load and dynamics in a way that lets you modify the way you steer... quite different than the OP brake + accel causing a steering input from the back end, not front end. But lots of things are different 2 wheel vs. 4 anyway.
You most definitely can. Steering is enabled by grip, and modulating the brakes at front or rear will change available grip. Every once in awhile I'll enter a corner too hot on the bike and a dab of rear brake will tighten things up.
as per other reply - you aren't steering you are settling chassis (which does affect compliance, hence grip in the sense that if you lose that you aren't able to steer). But as I said there, it's a similar enough thing I guess given all the different dynamics going on.
That's not the same effect, really. And trail braking is mostly (not exclusively) a front brake technique (in which case it's more likely reducing your turn in speed, as you really, really don't want to be on much front break and lean at the same time). It's mostly used to allow speed adjustment past the entry point without upsetting the chassis by a new application of brakes.
But I'll give you that it's vaguely similar to OP in some ways, so fair enough - cornering dynamics of 4 and 2 wheels are a bit apples and oranges anyway.
I grew up with tractors from my dad's landscaping business (old Case Construction Kings, with a PTO and farm-like attachment system rather than a backhoe). It was always funny at a worksite, when one of the college kids he'd hire needed to move a tractor out of the way. They'd get up in the seat and find this mass of unlabeled controls. There were two clutches, two brake pedals, and what looked like a regular shift lever on the floor and a regular accelerator pedal, plus all these levers they didn't recognize. They'd try to shift and it wouldn't move at all.
The floor gear shift was really just a range selector. Forward and reverse were on a shuttle lever on the steering column, and the PTO had its own transmission system, plus there was a global throttle lever in addition to the floor pedal.
Oh, and dad didn't even own a trailer. He'd drive those things on city streets at 30mph to get to jobs. It was insane in hindsight. He could have crushed a car with the bucket. And I'd ride at city street speeds sitting on a fender above an open back tire. Sheesh.
Yep. I decided to stop driving it before I drove it through a barn or something. I think the basic idea was sound, it makes the default behavior of "feet off the pedals" to stop.
The placement depends on the tractor model and make but it generally comes down to clutch on the left side, left and right brake pedal on the right side, foot accelerator either behind the brake pedals or below them. While working in the field you generally use a lever to control engine speed and as such mostly don't use the foot accelerator - other than to speed up for inclines etc.
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.
> 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.
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
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.
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.
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?
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.
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.
In RC planes with many engines differential thrust is relatively common (when you have 2 engines you mix the input signal from the yaw stick with the input signal from the throttle so that the the engine on the outside of the turn gives more thrust and the engine on the inside of the turn slows down - and the plane turns better). It's pretty intuitive when set up with good coefficients. Just feels as if the plane has bigger steering surface.
Maybe they could have done the same with breaking - just use the steering wheel position to choose the breaking power split between the wheels.
>I’m a decent stick shift driver and I can’t imagine dealing with four pedals.
Seems easy actually. These cars don't really have four pedals. Coulthard's had a clutch pedal but by this point (and to this day) F1 cars only use the clutch to start. So you're only using the extra brake pedal under acceleration and they are already using the left-foot for braking anyway. All you have to do is just change the left foot from one brake to the other after braking into the corner, it's not like heel-and-toe where you are actually pressing three pedals at once.
That’s discussed in the article. One of McLaren’s drivers wasn’t comfortable using the hand clutch, while the other was. So three pedals in one car, four in the other.
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.
It is a formula and whenever the formula gets revised there are these opportunities created that did not exist before.
There are some things that are ruled out of the essence of the formula and some things that get used to define it. For instance, the BT46 Turbofan that chucked stones out the back is not on. Meanwhile, the monocoque chassis with stressed member engine is part of the formula.
The rule changes to this year have resulted in two approaches to front wing aero, right now we don't know whether the Alfa Romeo approach is actually better than the Mercedes approach. That might be mere aero, nothing important, but think how it would work if anything was allowed so long as it was safe.
So there are some things that have to be ruled out such as the high nose that is better design but bad for potentially beheading drivers. If we let anything in then you could go back to the Williams FW14 and allow active suspension and a whole host of driver aids. You could even go further back and allow 6 wheelers, ground effect skirts and V12 engines. If the rules - the formula - was thus cast in stone - open to everything - then within 3-4 seasons the grid would distil into what was the de-facto winning formula. If six wheels really were better than four then every car would have six wheels.
Although the rulebook appears to stifle innovation it does promote it by these small and well thought out changes that happen every few years.
Having said that, I wish there was an 'anything goes' formula with a budget cap. So cars would have active aero, auto-pilot, super-capacitors, tuned-mass-dampers, low-profile tyres that weren't designed for needing pit-stops, performance enhancing drugs for the drivers, grid-girls advertising cigarettes - well maybe not some of these things that were once considered a vital part of the spectacle, but you get the idea.
One interesting suggestion I saw for controlling costs was putting a cap on downforce. This would end the incredibly expensive race to the bottom aero war. Better low profile tyres would be great for performance (and looks), but it'd be at odds with how important tyre strategy has become.
Downforce is being solved in the 2021 regulations. Ross Braun is on it, the car in front is to push the wake above the car behind rather than in its path.
Tyre strategy could be about running the same set of tyres all weekend. Normal cars don't change the tyres every hour. I know that the pit stop upsets the order a bit, however, if there were two sets of tyres for the weekend and you had to use both sets in the race then that could work out fine.
There is an environmental cost to lugging those tyres all around the globe, it is a bit out of touch with the times plus it doesn't say much about the product if it only lasts less than two hours. In Formula E they get this right and I am sure Michelin are getting the right message to their customers about what a great tyre they make.
The pit stop could even be a mandatory toilet break if the real point of it is to just upset the racing order. Or the drivers forced to pull into the pits to drink 500ml of water. Nobody wants to be dehydrated, do they? (Or to use the olden days phrase, 'thirsty').
I really think they need to reduce regulation so people can do creative stuff again. There used to be six wheelers or turbo vs non turbo but now it’s kind of boring. Maybe someone wants to try all wheel drive? Adrian Newey has been complaining about this for a long time.
They have put in all these restrictive rules and it’s still horribly expensive.
It's so heavily regulated that professional racing is no longer an engineering challenge.
Faster and more powerful cars can and are produced, but are barred for reasons of safety and, as the article demonstrates, mere choice of the governing body.
> It's so heavily regulated that professional racing is no longer an engineering challenge.
If you look at the different approaches taken with regards to aerodynamics (particularly this season) and engines then there's still plenty of room for engineering challenges (at least in F1, I don't know about other series).
Not unlike any other field where initial advancement is exciting and then it makes way to tiny, "boring", incremental evolution.
The second problem is indeed that regulation in the sport leaves less and less room for creativity in an attempt to level the playing field and prevent "abuse". I have a feeling that the regulation now looks more like a whitelist rather than a blacklist. Everybody is allowed to "innovate" the exact same thing.
I've found F2 to be much more exciting than F1 this year, and I think a big part of it is that the cars don't have as much "innovation", and are much closer to identical performance-wise.
Barring some surprise changes or race-by-race accidents/failures, we're looking a season of 1-2 Mercedes, 3-4 Ferrari, 5-6 Red Bull. That doesn't feel like racing.
Safety is a critical factor in the rulebook. The FIA want teams to be able to gain a competitive advantage through engineering, but they also want to maintain sensible corner speeds. A lot of technologies are banned in F1 simply because they work too well at making the cars faster, or they deliver speed improvements at the expense of stability.
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.
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..
I think it's more likely that the next season, everyone else would be doing the extra pedal thing too. That's kinda how F1 works. Someone comes up with an innovation, and the next season it's either banned or universally adopted.
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:)
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?)
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?
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.
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.
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.
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.