A similar thing is true when cornering a race car when measuring time through the corner.

Slow is smooth, smooth is fast.

How so?

"Faster" (higher speed) = wider cornering radius = more distance = slower

The distance has no effect.. Its all about speed, you want to take the line that lets you get through the corner while maintaining the highest speed. If you are going faster and spend as little time as possible breaking and accelerating you will gain time. Also a higher exit speed means you will be going faster for the entire straight after the corner making a very big time difference.

Your car, depending on how much grip it has + other variables, will have a theoretical minimum diameter circle it can drive around at various speeds. The higher the speed the bigger the circle. Finding your racing line is just a matter of fitting the biggest circular arc inside the space available in the corner.

Ideally you want to break in a straight line before the corner and reach the speed your car can drive the circle at at just the moment you enter it.

Theres more nuance when it comes to compound corners, FR vs FF cars, oversteer understeer, hills bumps etc. But the basic theory is simply fitting circles.

https://ibb.co/VY11TpTM

You are generally not taking a perfect circle corner. You can/should be slowing down as you enter the corner and then speeding up even before you exit. In this way you can shorten the distance traveled while getting a higher exit speed - sometimes higher than the largest possible circle corner. Optimizing this for the car/track/conditions is what makes for a great driver.

The distance is irrelevant.. It is true that depending on the car you may gain time breaking and accelerating while turning.

But that is a more subtle and advanced concept though (like dealing with elevation changes).. People should understand the big circle first.

In the context of winning a race you need to get the subtle and advanced concepts right or you will be in last place. If you are just driving on the street it doesn't matter.

Most times Ive seen anyone playing a racing game they seem to be totally clueless.. They dont even comprehend the big circle. They always go into corners way too fast, break super hard and then crawl out.

Its so common it surprises me racing games have always been so popular.

What I have also noticed is that over time racing games have changed their physics to be totally wacky in order to meet the general public's wacky expectations.. (eg. mario kart or GTA5) I cant play those games cus the physics are so strange.

I was referring to real world races where we cannot ignore physics.

Racing games are very different. They tend to have adaptive AI - you are more likely to win with the naive approach you describe than the physically perfect route. The physically perfect result will get your through the race several minutes faster, but the AI opponents become impossible to beat. Thus the ideal path is the worst thing you can learn. (I haven't played games in years, but IIRC the games you mention don't pretend to be about racing, I wonder how ones that pretend to be a real race compare)

?? I guess you havent played modern racing games. No-one races against AI, its all against other people. Games like Assetto Corsa and iRacing have very good physics models. Real race drivers use them to train and are often seen online.

The circle thing is aimed at most people here. If your average person implemented that they would dramatically improve their times.. All the other stuff (of which of course there is a lot) would result in relatively marginal improvements.

But the big picture is still "distance" - if you were to try to keep the same speed as the straightaway the required turning radius might be off the track entirely. So it's still generally necessary to slow down to some extent. I could have made that clearer.

But you exit going faster, which means you make up time on the straight after the corner.

It's a balance, many of these cars can accelerate and decelerate very hard so the time to get back to the full speed for the next section is fairly short reducing the effect of slowing down. The effect of taking a too wide racing line though means a large multiple in the distance travelled.

  > The effect of taking a too wide racing line though means a large multiple in the distance travelled.
So a better driver typically takes a shorter route than a less skilled driver? Can a very skilled driver get the Kessel Run down below 12 parsecs?

In ideal scenarios without having to account for other racers yes generally. In reality it's a difficult to talk about mix of driver skill, mechanical car performance and race strategy that determines the actual best line at any given moment though there is still one fastest theoretical line through a corner.

On race strategy it's rare for drivers to be pushing their cars to the limits for entire races because tire wear and the stops required to replace them is a major time sink because you can only drive so fast in pit lane so even the 1-2 second stops F1 cars go through today lose drivers position that then has to be regained using the extra performance fresh tires provides.

Then driver skill can put the better driver in the correct position to take the correct line more often when you include other cars in the mix and they also know better how to deal with suboptimal routes (eg being force to take an inside route by traffic so you have to know how much harder you need to break to not wreck into another car).

On an unrelated side note because I'm just personally annoyed by the 12 pArSecS!? misunderstanding. The 12 parsec run is impressive because Kessel is in a part of space ridiculously dense with hazards so the usual route to it loops through a narrow region where it's relatively safe to travel through. Han's 12 parsec run cut through the dangerous parts through either luck, superior navigation, or he was just lying the commentary is mixed. [0]

[0] https://static.wikia.nocookie.net/starwars/images/1/17/Kesse...

Cars can usually brake and turn harder than they can accelerate.

You also tend to spend more time on the straight after the corner, than in the corner itself

So you mostly optimise for corner exit speed, especially if the car has particularly slow acceleration and a long straight comes after the corner.

For F1 I was under the impression exit speed wasn’t as important as minimizing arc length of the turn.

They call that the geometric racing line and it might minimize the amount of time that it takes you to navigate one specific corner but if the corner is a hard braking zone followed by a long straight, your exit speed will likely be lower which will cost you time all the way to the next braking zone.

https://www.youtube.com/watch?v=uIbTPvHFf-w

https://driver61.com/uni/racing-line/

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Yeah depends on the corner but the general thumb-suck approximation is sound.

Assuming there is a long enough straight before the next corner

If there's banking, it can change things.