Clutch usage while on track

All that has to do with the power train, gearbox, clutch, fuels and lubricants, etc. Generally the mechanical side of Formula One.
hardingfv32
32
Joined: 03 Apr 2011, 19:42

Clutch usage while on track

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During yesterdays race the leader spun. He stated that he was nursing his clutch and that his activities caused him to spin.

I thought that the gearshifts are done without the clutch. Why would the driver need to be nursing the clutch if that is the case? What can the driver possibly do to improve the life of the clutch while on the track if it is always engaged?

I am ignoring anything to do with launches.

Brian

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chrisc90
36
Joined: 23 Feb 2022, 21:22

Re: Clutch usage while on track

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Torque demand from the engine? Semi-auto's have a peak torque value for clutches. If they could 'turn it down' to limit that slip then easy enough done through the steering wheel.

Just a possibility.

Tommy Cookers
617
Joined: 17 Feb 2012, 16:55

Re: Clutch usage while on track

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a few years ago a Honda paper showed how F1 clutch torque transmission was varied during shifts to minimise jerkiness
by another of those servo-grade electro-hydraulic actuators - and for about 10-20 milliseconds

but at least one other poster doesn't believe this applies (currently or ever ??)
Last edited by Tommy Cookers on 01 Aug 2022, 20:57, edited 1 time in total.

TimW
36
Joined: 01 Aug 2019, 19:07

Re: Clutch usage while on track

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Last year McLaren (and others) wanted to change the clutch after sprint races, because of worries their clutch would not survive a sprint + full race distance. The issue was not so much the starts and pit stops, but the total number of gear shifts IIRC.

Which means it is active during gear shifts

Jolle
132
Joined: 29 Jan 2014, 22:58
Location: Dordrecht

Re: Clutch usage while on track

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In the early days of paddle shifters, it’s was just a ignition advance/cut while charging gears. Now with better controls, sensors and computing power, the clutch is getting some use again in certain aspects of changing gear (mostly downshifts I presume).

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Big Tea
99
Joined: 24 Dec 2017, 20:57

Re: Clutch usage while on track

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Jolle wrote:
02 Aug 2022, 00:48
In the early days of paddle shifters, it’s was just a ignition advance/cut while charging gears. Now with better controls, sensors and computing power, the clutch is getting some use again in certain aspects of changing gear (mostly downshifts I presume).
Surely it would be rev matching more than clutch slip that makes a good change out of a bad one?
When arguing with a fool, be sure the other person is not doing the same thing.

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Zynerji
111
Joined: 27 Jan 2016, 16:14

Re: Clutch usage while on track

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Big Tea wrote:
02 Aug 2022, 00:50
Jolle wrote:
02 Aug 2022, 00:48
In the early days of paddle shifters, it’s was just a ignition advance/cut while charging gears. Now with better controls, sensors and computing power, the clutch is getting some use again in certain aspects of changing gear (mostly downshifts I presume).
Surely it would be rev matching more than clutch slip that makes a good change out of a bad one?
I'm sure it's a combination. Slipper clutches are the rave in other sports.

hardingfv32
32
Joined: 03 Apr 2011, 19:42

Re: Clutch usage while on track

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We are missing something regarding the driver nursing the clutch. So far everything mentioned does sounds like a legitimate use of the clutch. These activities can all be actively control be the computer much more efficiently than any driver could. There is just no reason to expect the driver to interact with such automated activities and be able to do it more effectively.

Quite the mystery.

Brian

TimW
36
Joined: 01 Aug 2019, 19:07

Re: Clutch usage while on track

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hardingfv32 wrote:
02 Aug 2022, 20:20
We are missing something regarding the driver nursing the clutch. So far everything mentioned does sounds like a legitimate use of the clutch. These activities can all be actively control be the computer much more efficiently than any driver could. There is just no reason to expect the driver to interact with such automated activities and be able to do it more effectively.

Quite the mystery.

Brian
I don't think he was operating the clutch. He reported clutch slip, and they told him to press 'fail 20' and some other changes. They told him it would impact drivability.

My guess a sensor issue, and the sensor bypass caused sub optimal clutch operation(but less slip).

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Zynerji
111
Joined: 27 Jan 2016, 16:14

Re: Clutch usage while on track

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TimW wrote:
02 Aug 2022, 20:37
hardingfv32 wrote:
02 Aug 2022, 20:20
We are missing something regarding the driver nursing the clutch. So far everything mentioned does sounds like a legitimate use of the clutch. These activities can all be actively control be the computer much more efficiently than any driver could. There is just no reason to expect the driver to interact with such automated activities and be able to do it more effectively.

Quite the mystery.

Brian
I don't think he was operating the clutch. He reported clutch slip, and they told him to press 'fail 20' and some other changes. They told him it would impact drivability.

My guess a sensor issue, and the sensor bypass caused sub optimal clutch operation(but less slip).
I would think a "failed" sensor would then resort to a derived answer by doing math on other sensor readings. Thus, becoming a psudo-assumption, and sub-optimal over a direct reading.

TimW
36
Joined: 01 Aug 2019, 19:07

Re: Clutch usage while on track

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Zynerji wrote:
02 Aug 2022, 20:41
TimW wrote:
02 Aug 2022, 20:37
hardingfv32 wrote:
02 Aug 2022, 20:20
We are missing something regarding the driver nursing the clutch. So far everything mentioned does sounds like a legitimate use of the clutch. These activities can all be actively control be the computer much more efficiently than any driver could. There is just no reason to expect the driver to interact with such automated activities and be able to do it more effectively.

Quite the mystery.

Brian
I don't think he was operating the clutch. He reported clutch slip, and they told him to press 'fail 20' and some other changes. They told him it would impact drivability.

My guess a sensor issue, and the sensor bypass caused sub optimal clutch operation(but less slip).
I would think a "failed" sensor would then resort to a derived answer by doing math on other sensor readings. Thus, becoming a psudo-assumption, and sub-optimal over a direct reading.
I would love to know the details behind stuff like this. They should introduce a new rule that team-driver communications are only allowed if they are explained afterwards on f1technical!

hardingfv32
32
Joined: 03 Apr 2011, 19:42

Re: Clutch usage while on track

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Interesting that an assumed negative impact on drivability did not seem to hurt his pace noticeably.

So maybe they just dialed out some of the 'shift smoothing' that was provided by the slipping the clutch. The driver was caught out by the harsher clutch application when it was used for the first time.

I wonder if someone just had the correct solution in their head, code and all, or do they use a program that lists the possible causes and solutions for a given issue is input into the program. The latest airliners are starting to do this instead of using a big manual. Time is very important in both applications.

Brian

johnny comelately
110
Joined: 10 Apr 2015, 00:55
Location: Australia

Re: Clutch usage while on track

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Regulations I didnt know existed
9.9.4 The maximum permitted duration for down changes and up changes is 300ms and 200ms respectively. The maximum permitted delay for the latter is 80ms from the time of the driver request to the original gear being disengaged.
I had the impression that the GCU reset would have just changed the position of the actuator.
Couldnt see if that was "not permitted"
the 2022 digitised version of this Image :wink:

Jolle
132
Joined: 29 Jan 2014, 22:58
Location: Dordrecht

Re: Clutch usage while on track

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johnny comelately wrote:
02 Aug 2022, 22:29
Regulations I didnt know existed
9.9.4 The maximum permitted duration for down changes and up changes is 300ms and 200ms respectively. The maximum permitted delay for the latter is 80ms from the time of the driver request to the original gear being disengaged.
I had the impression that the GCU reset would have just changed the position of the actuator.
Couldnt see if that was "not permitted"
the 2022 digitised version of this https://www.mxstore.com.au/assets/alt_1 ... %3A24%3A30 :wink:
If you think about it, quite a logical rule. A bit of delay is permitted because it's a digital signal but can't be misused to make it in practice an automatic gearbox or align gearshifts automatic with the best shift revs (or even, use it as a crude way of traction control)

saviour stivala
51
Joined: 25 Apr 2018, 12:54

Re: Clutch usage while on track

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Why would the clutch on a formula one car be used during a race?. For a formula one clutch to slip when it is not being used, even for a bad clutch, the release mechanism will have to be plying a part in it.