Telemetry thread 2023

For ease of use, there is one thread per grand prix where you can discuss everything during that specific GP weekend. You can find these threads here.

Should a car telemetry thread be created

Yes
82
98%
No
2
2%
 
Total votes: 84

bagajohny
bagajohny
4
Joined: 01 Jul 2021, 08:58

Re: Ferrari SF23

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Andi76 wrote:
05 Mar 2023, 10:29
On motorsport.com Matt Kew has published a good analysis of the GPS data from the SF-23 and the RB19:

"...the RB19 can't be caught at early power, even if Leclerc was able to get back on the throttle faster in the tight first corner, looking ahead to the decisive Q3 laps.But Verstappen's advantage is only short-lived: on the back straight towards turn 4 it's the SF-23 that has the higher top speed at 304 km/h - Verstappen only gets to 301 km/h. Interestingly, this is once again exactly the opposite of last year, when Red Bull had the upper hand on the straights. The RB19 seems to have more downforce, as Verstappen is faster in the right-hand corner and the more brutal medium-fast Turn 7. In the fluid middle section in between, however, Leclerc again dictates the pace. And that's the trend for the rest of the lap, too: Red Bull accelerates better out of the notorious Turn 10, a downhill left-hander, and takes more speed through the uphill Turn 12. Verstappen finds time again in Turn 13, too, and has an advantage before the penultimate straight, but the low-drag Ferrari makes up for it by arriving four km/h faster in the final braking zone.

At the apex of the final corner, the Ferrari is actually faster, just as it was in 2022, before the Red Bull sets the benchmark again on acceleration. Only at the finish line can the Ferrari crack the RB19's speed of 293 km/h again."

In relation to the Aston Martin, the SF-23 loses especially in the braking zones and the slow apexes. Alonso's car has, according to his analysis, the better mechanical grip, but is also the slowest of the three cars on the straights, where he then also loses a lot of time compared to the SF-23.

I think this shows that Ferrari worked on the weaknesses of the F1-75 in the SF-23, but they had to trade some of its strengths for it. Since Red Bull, at least in this analysis, seems to have done the same, the roles are reversed to 2022 - the Ferrari is the faster car in terms of top speed while the Red Bull gains time in the corners. What is not taken into account here, however, is that there will still be some change in the SF-23 in terms of downforce. The new rear wing, which Ferrari says is a "project," seems to aim to make up for the lack of downforce on the rear axle compared to Red Bull with comparatively minimal gains in drag. If the front axle can be compensated accordingly, I think it doesn't look too bad that Ferrari retains a minimal advantage in top speed, but hardly loses anything in the corners.

This would also explain the confidence that prevailed after the tests and the relaxed mood after qualifying, which is in complete contrast to the suddenly emerging rumors about correlation issues and the statements made so far. Whereas everything fits together when you have achieved your goals and are aerodynamically very efficient and "only" need to complete a project to find the last points of downforce, knowing that this only reduces the advantage you have in terms of top speed to the extent that you are still faster, even if only minimally. The efficiency of the SF23 can be seen on this telemetry :

https://postimages.org/

Also that Leclerc often can go on the throttle earlier than Verstappen is encouraging.

Of course this is a speculation and a theory of mine, but if you take the facts, the statements of the engineers and the behavior of the whole team as a basis, a quite plausible and logical one. If they had actually correlated issues, which with a gap of 3 tenths to the excellent Red Bull and the fact that they have the second best car anyway sounds more like a joke, they would hardly be as relieved and confident as they were after qualifying.

Finally, the race today will finally reveal many question marks for us. It will be crucial if Ferrari has already overcome its biggest weakness with the SF-23. The longrun data itself (see yesterday's post) suggests that at least Leclerc's car is expected to show a strong improvement. However, this looked quite different with Sainz and the Red Bull, Aston Martin and Mercedes engineers rather predict that Ferrari will have strong problems. The driver has a very important role when it comes to tire desgradation. A race tire goes through various heat cycles during a race. Generally, a tire becomes harder after each heat cycle. Experienced drivers take good care of their tires and try not to let them build up too much heat. A more evenly heated tire goes through fewer heat cycles and maintains its optimal grip for a longer time. But also on the part of the tire manufacturers is already taken precautions here. A new racing tire, unlike cars on a normal road car, is not fully cured. Because of the extreme heat to which the tire is exposed, tire manufacturers leave parts of the curing process to the racers. If a fully cured tire were taken to the track, the tire would be much harder from the start, with corresponding effects on grip and lap times. Tire engineers understand that heat changes the rubber compound of the tire, so they plan ahead for the curing process to take place on the track. This is one of many reasons why race tires are much softer than normal tires and the driver has the task and control over how the tire is cured and how much it cures or stays in an optimal grip range. But other things also have an important influence. A racing tires actual compound softness when its in action is only partly to do with the base softness resulting from its ingredients. The other two main determinants are the tires temperature and the contact frequency. These work in opposite directions. When the temperature rises the compound becomes softer, when contact frequencies rises the compound becomes harder. The suspension is the tool that influences that and also is the tool to bring the tire to its optimum state, called vitreous transition. But its a delicate balancing act. Contact frequency is about how the loads react upon the rubber, what is not consistent becauser rubber is viscoelastic material. Up to a point the rubber will accept the incoming energy and react against it, trying to spring back in the opposite direction of the load and thereby creating grip. Beyond that point the rubber cannot regain shape quickly enough to absorb the next input. The contact frequencies get to high. This has the effect of stiffening and hardening the compound. The higher the contact frequency, the more temperature you need to compensate in order to keep the tire at its intended compound softness. So there are quite a few different influences and mechanisms that play a role here and I'm curious if the SF-23 and its drivers (both play a role, car and driver) work better here.

It also remains to be seen to what extent the Red Bull will be ahead in race pace. I wish everyone a lot of fun and am curious what will turn out. But I think that the SF-23 has great potential and can make bigger steps than the RB19.
Last year if I remember correctly RB had 10kmph advantage over Ferrari in straight line. Now I know part of it was due to ferrari turning down the engine. But what I want to ask is the 4kmph advantage that SF23 has over RB19 is how much significant? When comparing the top speeds of different cars how much advantage is
  1. not significant (will not help in overtaking)
  2. significant (will definitely help in overtaking)
  3. more than significant (which will help in overtaking even without DRS)
I would like to know some approx numbers please.

Xyz22
Xyz22
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Joined: 16 Feb 2022, 20:05

Re: 2023 Scuderia Ferrari F1 Team

Post

dialtone wrote:
05 Mar 2023, 07:10
Xyz22 wrote:
05 Mar 2023, 04:31
I saw an interesting tweet on my timeline. A screen from an user on IG which is making analysis on telemetry. He is saying that Charles has completely changed his driving style to adapt to the SF 23.. Specifically, according to him, he is not trail braking any more in the corners, and he is braking much earlier overall, having a lower minimum speed in the entry of the corners to minimize understeering, getting better traction and thus achieving a better top speed in the straights. According to him, it's possible to see this even compared to Sainz.

Dialtone could you confirm this is true? You're the only one i trust regarding telemetry analysis : )
lmao, thanks for the confidence :).

https://i.imgur.com/atgRJZT.jpeg

2022 LEC Q v 2023 LEC Q

* Yeah I think it's a valid observation, this year LEC's braking is more on/off with the throttle, while last year he would get on the brakes but stay on the throttle during corner entry, see T1 red throttle trace gets to 0 very close to the apex. Approach to T1 is completely different compared to last year, it's worse IMHO as he loses almost 0.2s just in T1, but it's different, he brakes early and takes it almost like a V corner, I think VER has this style a bit more than LEC.
* Another curious corner is T11 (3400m) where LEC last year would quickly get on the throttle to force the car to steer through the corner almost immediately after releasing the throttle, this year he did the same but not as aggressively.
* At 900m (right after the first corner) you can really see the insane improvement in acceleration thanks to engine being full beans (it wasn't full beans last year here yet), and the new aero package, LEC comes out of T1 worse than in 2022 by some margin and is 7kph slower at the apex there, and yet once he turns the car, matches the F1-75, on the early part of traction they are together, then the SF-23 just takes off from 120kph to 240kph that acceleration curve is a massive improvement.
* Even with the smaller wing, at T5-6-7 the car matches the one from last year perfectly, in fact even gains a little bit in those 3 corners, sign that it's true they managed to get more downforce out of the car even with the smaller wing and aero efficiency.

All in all the instagram post is correct, so tip of the hat for noticing this in the telemetry to whoever was on IG. I would also observe however that this could be due to the balance issues, but it could also help preserve the rear tires at the same time.
Thanks as usual, Dialtone for taking the time to make this analysis. It's really appreciated.
wowgr8 wrote:
05 Mar 2023, 11:32
Xyz22 wrote:
05 Mar 2023, 04:31
I saw an interesting tweet on my timeline. A screen from an user on IG which is making analysis on telemetry. He is saying that Charles has completely changed his driving style to adapt to the SF 23.. Specifically, according to him, he is not trail braking any more in the corners, and he is braking much earlier overall, having a lower minimum speed in the entry of the corners to minimize understeering, getting better traction and thus achieving a better top speed in the straights. According to him, it's possible to see this even compared to Sainz.
Could you link this?
I didn't link it because it's written in italian.

Image
Image

"Leclerc has changed his driving style. Remember last year's Trail Braking? FORGET IT! Both in comparison to Sainz and Verstappen, it can be seen how Charles anticipates the braking point, which leads him with a lower speed at the apex of the corner <- white arrows.

The green arrows instead highlight how an early braking allows Leclerc to be ahead every 3/4 of a stretch and with higher top speeds at the end of the straights.

This allows him to minimize the shortcomings of the SF-23: understeer with consequent tire degradation."



"They can say what they want but the car is going slower than it should. From the tests to the race weekend, improvements have been made in entry and traction (PU) but the SF-23 doesn't turn in the middle of the corner. There is a lot of understeer. For now, they are holding on to power and efficiency."

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jumpingfish
53
Joined: 26 Jan 2019, 16:19
Location: Ru

Re: 2023 Scuderia Ferrari F1 Team

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bagajohny wrote:
05 Mar 2023, 13:43
Last year if I remember correctly RB had 10kmph advantage over Ferrari in straight line. Now I know part of it was due to ferrari turning down the engine. But what I want to ask is the 4kmph advantage that SF23 has over RB19 is how much significant? When comparing the top speeds of different cars how much advantage is
  1. not significant (will not help in overtaking)
  2. significant (will definitely help in overtaking)
  3. more than significant (which will help in overtaking even without DRS)
I would like to know some approx numbers please.
4km/h at the end of the straight line doesn't look so significant

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Oehrly
5
Joined: 08 Jan 2018, 17:53

Re: Telemetry thread 2023

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@BigBeansBoy, very nice analysis of the lateral and longitudinal acceleration of the cars. Can you pinpoint the potential Mclaren outliers under breaking (and maybe under acceleration as well) to specific laps and breaking zones? I don't know how your analysis code is structured of course, but is that possible? I'd like to have a look at the data there myself and check if I find anything that is interesting.

niccoaero
niccoaero
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Joined: 18 Nov 2022, 12:19

Re: Telemetry thread

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hollus wrote:
03 Mar 2023, 22:47
BigBeansBoy wrote:
27 Feb 2023, 07:42
AR3-GP wrote:
27 Feb 2023, 07:21
Can you explain how each dot on your acceleration scatter plots is acquired? Is this the acceleration measured at a certain sampling rate? Over 1 lap? Over many laps? I don't understand.
I should've specified more how this data was generated. This data is the fastest lap of each driver from the third day of testing.

Longitudinal acceleration was fairly simple to calculated. The telemetry data available from the fastf1 python package contains a speed in kph (top plot in figure 1). From this we can take a derivative with respect to time using the real time associated with the telemetry data (so we don't have to worry about irregular sampling rates). This data is then smooth with a linear convolution.

Lateral acceleration is a little more complicated and requires a few assumptions. I took this to be 798kg for all three drivers, this likely incorrect, but hopefully consistently incorrect.
The lateral acceleration can be calculated as:

Code: Select all

a = v^2/R
where v is the instantaneous velocity and R is the instantaneous turning radius. I'm not modeling horizontal slip velocity but I don't think that will impact the trends seen in the data, just the absolute numbers.
I mentioned above the velocity can be acquired directly from the telemetry data. The radius is not so simple. Instead we need to plot the position of the car and calculate the first and second derivatives of each cardinal direction. A more detailed write-up regarding curvature can be read here: https://mathworld.wolfram.com/Curvature.html. Then the radius is simply

Code: Select all

1/k
.
This can then be calculated at each point along the lap and similarly smoothed as the longitudinal acceleration.

The absolute values of the these figures should be taken with huge pinch of salt, but the comparisons should be largely valid to make, assuming similar weights.
I tried to find the Radius (R) with the following formula: k=(x'y'' - y'x'') / (x'^2 + y'^2)^(3/2) et R = 1/k, but I think that something is wrong because no '0' values for the Radius come out when the car is running on a straight line. Could you please explain better how you handle this?

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Vanja #66
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Re: Telemetry thread 2023

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Here's something interesting, Max was slower on all straights in the first stint than other two, did not go over 302kmh on the main straight in the first stint from what I saw. Later he was around 306-310, all with DRS off and no slipstream of course.

Perez didn't do this and neither did any other driver in any other car. Was that a setting to be slower on acceleration with full-fuel car to preserve tyres better? I didn't see noticeable difference in throttle % on f1-tempo.

Image
And they call it a stall. A STALL!

#Aerogimli
#DwarvesAreNaturalSprinters
#BlessYouLaddie

AR3-GP
AR3-GP
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Joined: 06 Jul 2021, 01:22

Re: Telemetry thread 2023

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Vanja #66 wrote:
08 Mar 2023, 16:52
Here's something interesting, Max was slower on all straights in the first stint than other two, did not go over 302kmh on the main straight in the first stint from what I saw. Later he was around 306-310, all with DRS off and no slipstream of course.

Perez didn't do this and neither did any other driver in any other car. Was that a setting to be slower on acceleration with full-fuel car to preserve tyres better? I didn't see noticeable difference in throttle % on f1-tempo.

Many of those drivers were beneffiting from slip streams on lap 5 (Leclerc, Perez, Hamilton).

By lap 28 the race had settled down considerably in terms of ERS attack modes and what not. Verstappen’s car was also lighter on lap 28 than lap 5. His top speed seems to shift gradually which I associate with the fuel consumption.

Image

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Vanja #66
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Re: Telemetry thread 2023

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Not really, they were far enough apart for that. Also, their top speeds on straights were consistent, only with DRS on there are notable jumps. Max' top speed in first stint seems to be lower due to later acceleration vs LEC and HAM and other drivers, but when I overlay his own laps in different stints there isn't a lot of difference in throttle application, not more than other drivers'. So the only thing I see which makes sense is different mgu deployment settings, lower on purpose in first stint? No idea... :?:
And they call it a stall. A STALL!

#Aerogimli
#DwarvesAreNaturalSprinters
#BlessYouLaddie

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Juzh
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Re: Telemetry thread 2023

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I think we'll have to wait for a race when RB have to turn up, as Verstappen's race is very hard to read because he didn't push the car on a single lap and made 10 or more switches on the engine trough the race, same with perez, amount of stuff red bull drivers have to adjust on steering wheel is probably triple the amount of any other.

Verstappen was is in a relatively low energy recovery mode for the duration of the race (strat 8 ) because higher recovery was giving him rear locking, highest he went was strat 5 for a few laps, whereas perez was in strat 3 for quite some time. This could explain those last few kmh on top end on some straights. Still I find it funny because he was coasting so much it seems weird he'd be low on energy at any time.

with around 10 laps to go both RBs lowered engine settings, i would presume ICE modes which are normally not allowed to be changed, as decreased performance was specifically mentioned by both engineers on radio, so this further complicates things. I think this was due to clutch getting very hot, so they wanted to put less stress trough it.

RB ran higher wing aoe - there's another few kmh compared to rest.
Honestly, it's impossible to decipher these cars with all these settings.

AR3-GP
AR3-GP
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Re: Telemetry thread 2023

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Vanja #66 wrote:
08 Mar 2023, 20:31
Not really, they were far enough apart for that. Also, their top speeds on straights were consistent, only with DRS on there are notable jumps. Max' top speed in first stint seems to be lower due to later acceleration vs LEC and HAM and other drivers, but when I overlay his own laps in different stints there isn't a lot of difference in throttle application, not more than other drivers'. So the only thing I see which makes sense is different mgu deployment settings, lower on purpose in first stint? No idea... :?:
I probably have not looked into the telemetry as deeply as you have but these were the gaps on lap 5:

Image

It is all well within slip stream distance.

Lap 11:

Image

Lap ~22:
Image


Leclerc has to use ERS mode down the main straight to defend from Perez for pretty much the first 25 laps which explains why he's so quick down, and why Perez was also quick (slipstream). After Leclerc get's overtaken (around lap 26 or 27), Ferrari most likely concede and just try and bring it home (high deployment turned off).

The others have a small slipstream everywhere. Hamilton has Sainz's slipstream pretty much through the first 25 laps in addition to being chased by Russell and Alonso.


Don't get me wrong, I'd love to imagine that RB have it in the pocket as supremely as that ( :lol: ), but I don't think they have THAT much in the pocket that they aren't even using the ERS from lap 1. It all just looks like coincidence to me. Many of those guys you cited have slip streams and/or are using ERS modes to keep out of DRS range.

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Vanja #66
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Re: Telemetry thread 2023

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Juzh wrote:
08 Mar 2023, 20:37
Honestly, it's impossible to decipher these cars with all these settings.
Thanks, really appreciate it :) Do you think this could have a slight positive impact on Max' tyre deg?

AR3-GP wrote:
08 Mar 2023, 20:42
Don't get me wrong, I'd love to imagine that RB have it in the pocket as supremely as that ( :lol: ), but I don't think they have THAT much in the pocket that they aren't even using the ERS from lap 1. It all just looks like coincidence to me. Many of those guys you cited have slip streams and/or are using ERS modes to keep out of DRS range.
It could be, but I'm not sure... Last year every driver said you need to get really close to the car ahead to get the right slipstream, even with DRS. I will just leave it here, it's probably nothing or just the ERS setting as Juzh mentioned. :)
And they call it a stall. A STALL!

#Aerogimli
#DwarvesAreNaturalSprinters
#BlessYouLaddie

dialtone
dialtone
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Re: Telemetry thread 2023

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I did the analysis in Miami last year, there is still the post in the forum but the impact is minimal past 2.5s behind, less than 1kph probably.

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chrisc90
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Re: Telemetry thread 2023

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Does anything look obvious with the different ERS settings/strat mode when GP told Max to change modes in the final laps of the race?

dialtone
dialtone
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Re: Telemetry thread 2023

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dialtone wrote:I did the analysis in Miami last year, there is still the post in the forum but the impact is minimal past 2.5s behind, less than 1kph probably.
viewtopic.php?t=30435

This was my admittedly basic study

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henry
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Re: Telemetry thread 2023

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Juzh wrote:
08 Mar 2023, 20:37
.
….
Still I find it funny because he was coasting so much it seems weird he'd be low on energy at any time.

….
Although coasting reduces the energy deployed from the ES , it reduces the energy recovered to the ES more.

Something like 40kW less deploy but 120kW less recovery. This applies so long as the speed is high enough that the aero drag is higher than 120kW.
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