Imola this time around

[dumrick]

To Ciro:
Isn't there a huge difference between designing roads and tracks, in the sense that in the earlier you must make it comply with the dynamic abilities of the cars and, in a racetrack, you are supposed to challenge them?

[zac510]

Good point dumrick, designing the tracks is probably becoming more like designing a road!

Ciro, but as the speed changes through the corner, the CofP will change. Now I understand your avatar at least

[Ciro Pabón]

This is just one example of what intrigues me: compare the entry and exit curves of Repsol, at Catalunya: it is (maybe) only important to have transition (yellow) on the exit? Only when you are accelerating?

What about the entrance (red)? The geometric designer supposed that you could go from straight to curve in an instant at the entrance, because you go from straight (green) to circular (red) without any apparent transition (and I worked with 5000x3600 pixel photos; if this red thing is not circular I will swallow my hat. Well, my hard hat).



Nobody will take the entrance to this curve following the inner kerb, not even Superman. You should flick your wheel from straight to curve in the blink of an eye.

Besides, imagine the frontal view: the green entrance (to the left, of course) is flat (well, almost). The red curve has superelevation. Where is the transition from flat to inclined made? In the straight. What about the lateral displacement of COG at the entrance? This is the kind of design I do not understand. I would not make the humbler road in Colombia like this...

Can somebody explain this (apparently) poor design?

[manchild]

...Nobody will take the entrance to this curve following the inner kerb, not even Superman...

I agree, driver must keep car outside approximately all the way to that yellow mark 112,91.

[Ciro Pabón]

To Ciro:
Isn't there a huge difference between designing roads and tracks, in the sense that in the earlier you must make it comply with the dynamic abilities of the cars and, in a racetrack, you are supposed to challenge them?

Yes, you could challenge them, instead of ignoring them (apparently)...

Ciro, but as the speed changes through the corner, the CofP will change. Now I understand your avatar at least

Well, I think that for you to understand it completely you could take a look at this:



It is funny that F1 cars (as Manchild says) follow the curves of nautilus or the growing of plants. Beauty is in the eye of the beholder...

And, yes Virginia, there is braking at the entrance and acceleration at the exit and CofP change. This is the point: you have to change the sideslope at this points, not in the straight, preferably while you are changing the radius from infinity (straight) to the value for the curve.

Well, enough of going out of the thread.

[zac510]

Can somebody explain this (apparently) poor design?

Ciro, who said the corner is of poor design?

It is not unlike the famous Parabolica!

[Ciro Pabón]

Ciro, who said the corner is of poor design?

It is not unlike the famous Parabolica!

I say so. I may be mistaken, of course. Please, try to imagine the vertical view of the road... there are problems with the superelevation, as I tried to explain (without succes, I guess). You have superelevation on a straight!

The Parabolica is precisely a long, long transition curve: hence its name, even if, at that time, logarithmic spirals were still waiting to be applied to road design. And I think it is a really dangerous curve, if you ask me, because it is not well suited to modern cars. http://www.f1technical.net/articles/20 This, or modern cars are not well suited to the curve, make your pick.

I guess the difference is small to the untrained eye... Actually, to "correct" Repsol you should move the curve less than a meter or so. But you have to do it along the whole curve.

[zac510]

The challenge of Repsol must be the hidden apex. If you miss it you would lose a lot of speed.

[Ciro Pabón]

The challenge of Repsol must be the hidden apex. If you miss it you would lose a lot of speed.

Good point. You are right. The apex is actually at the line marked 104.52 (which is actually the length of the curve in meters), in the middle of the red curve.

It is not closer to the point of union of the red and yellow lines, at the top of the photograph, as you could think at first sight.

Actually, this depends heavily on the yellow part of the track: I think it depends on how you regulate your acceleration at the exit what indicates if you are going to exit with understeer or not. A more powerful car should take an earlier apex.

[DaveKillens]

It is my philosophy that a racing track should be quite different than one used for day to day traffic. In road engineering, it's a responsible engineer who designs a roadway that throws no hidden or unwanted surprises at an unwary driver. A good example would be an on ramp for an expressway. Uusally they are 270 degrees, and take the vehicle from 50 kph to 100 kph. So as the driver turns and accelerates, the road slowly unwinds and gently feed them towards the main artery. To have a sudden diminishing radius corner would be a definite source of accidents.
But on a racing track, it should be just the the opposite. In the history of tracks, they were first adopted from local roads, which at that time were just laid out as the locals and terrarin allowed. And the drivers just had to deal with whatever was there. Yes, there were definitely some very unsafeplaces, and sadly, to this day there are still some being used. The Isle Of Man be historic, but as dangerous as they come.
But my own personal definition of racing is to have the drivers deal with difficult terrain, that is one of the deciding factors in skill. If you designed a track that did not challenge the driver, you wind up something called "Talladega".
Safety must never take a back seat to anything else, but for me, to design in awkward and challenging sections is what I prefer. The old Watkins Glens track had a long straight, followed by a drop in elevation, followed immediately by a high speed right turn. Get it anwhere just a bit off, and you were in very serious trouble. To eliminate that section for fast cars is logical and safe.
Personally I like tracks that challenge a driver, force them to deal with awkward and challenging sections. Off cambers, esses that unbalance the car, things that force mistakes, and separate the drivers.

[dumrick]

My point exactly. I understand Ciro's view from a point of view of someone interested in minimizing the risks involved in road car operation. However, that's not the same the philosophy as that of a race track. If that was the case, any road would be testing the dynamic abilities of cars as good as a race track, and the Nordschleife (if it was designed under road engineering best principles) would be an ordinary place (just to give an example).

[DaveKillens]

It's almost scary how Alonso went out in second practice and laid down the fastest time. I know he's good, but I have to tell you that this guy continues to amaze me at just how good he is. Yea, he's got a great team behind him and a great car under him. But he just goes out there as if there's no pressure or anything and just burns up the track.

[Principessa]

Correct Dave! Alonso seems so relaxed. I hope he won't have any problems during the race and than I think it will be great fight in the front.
I expect Alonso, Fisico, Schumi, Kimi and Jenson at front!

[m3_lover]

I wonder if Ferrari helped out with this

http://www.gp2006.com/news/controller.p ... s_id=18791

[Ciro Pabón]

Safety must never take a back seat to anything else, but for me, to design in awkward and challenging sections is what I prefer.

Well, I feel like a very lonely road designer in this forum...

I will not "cease and desist", of course. I have seen you in action before guys, you can understand this too!

Awkward and challenging are not synonymous. I bet you would be dismayed if some fan argued for, let's say, fading brakes or aero packages that did not work as designed after 200 khp, because they were challenging. How in heaven do you explain to him that there are other challenges different from those?

I was explaining that you can have a design with multiple optimal trajectories. What else could be more challenging?

Schumacher and Alonso (my God, they really have credibility!) argue against this same line of thinking with this particular Imola chicane. The old chicane was inhumane and a risk for suspension breakage. Somebody finally agreed with them, but you can conclude by this clear example that there is no fan pressure for good circuits because they do not distinguish a good one from a bad one.

This is why (in my opinion, not so humble) you cannot pass in some circuits. Do you want passing? Hey, let's make a wide curve. Just for testing, just one, maybe you will like it. I still do not understand why the ONLY solution for passing are hairpins and the ONLY solution for slowing down the cars are chicanes.

It took the death of a world champion for run-off areas to be implemented. It took the death of a NASCAR champion for the understanding of basilar skull fractures to slowly seep down the ranks and then, and only then, HANSes were made compulsory.

Nowadays, when tracks are starting to be subject of competition, we are slowly seeing new tracks with a better (arguably!) design. Old and improvised tracks are being left aside.

Ignorance is no substitute for intelligence. I assure you: some circuits seem terribly poor. They are really old and made when cars were other thing. You can do a really good and challenging circuit out of wisdom. Until somebody shows me that this (apparently) poor design is really a very well thought subject, I will respectfully disagree with the people that thinks that tracks are some sort of last thought when design is required.