Can the MGU-K harvest or deploy under its own control? And related questions.

[hollus]

There was a lengthy, 8 pages, I believe, discussion in the Ferrari PU thread on this very matter.
Then there was the same discussion starting in the Honda PU thread, and quickly turning sour.

Before it pops again on another PU thread, it is moved here.

Right or wrong, based on real or false information, or on information just heard or on information in technical directives that we cannot access, it was often an informative conversation.
It can continue here, but it won't be allowed to block conversation in other threads.

The particular questions being formulated and/or answered centered around whether the MGU-K can decide to deploy energy when the accelerator pedal is not pressed, or maybe to harvest when the brake pedal is not pressed.
It further pertains whether the MGU-K can do funny things like alternate between both behaviors, possibly in a dance involving the MGU-H.
It also extends to whether the control unit can decide these things on its own and it also extended to whether the driver has or not direct control over throttle bodies, etc.

The first posts are directly moved from the Honda PU thread.

I believe all the people involved know exactly what this is about, so now this is the new home for that discussion. May it be fair, may it be informative and may it be civil. But specially, may it be in this thread only.

[hollus]

Depends how much of a spike is there, given that you're changing up ratio's so you have less leverage than the previous gear and that the driveline is pretty compliant so it can store and release the energy over a longer period, I wouldn't think you'd need much control beyond MGU-K/H generating for a brief moment to turn that spike into simply a gradient to the next gear.

For the MGU-K to deploy the accelerator pedal will have to be activated by the driver, likewise for the MGU-K to generate the brake pedal will have to be activated by the driver. yesterday and the day before while testing red bull drive-shafts weren't up to the job (compliant) in storing and releasing the energy.

[hollus]

Oh not back to that again are we? The MGU-H and K can generate without the driver ever touching the brake pedal, and there's nothing in the regulations that say otherwise.

[hollus]

Oh not back to that again are we? The MGU-H and K can generate without the driver ever touching the brake pedal, and there's nothing in the regulations that say otherwise.

Oh yes back to that again we are. The MGU-K and not the MGU-H can only generate when the driver activate the brake pedal. because we don't agree about it doesn't mean you are right and I am wrong, its just that we don't agree.

[hollus]

Oh not back to that again are we? The MGU-H and K can generate without the driver ever touching the brake pedal, and there's nothing in the regulations that say otherwise.

Oh yes back to that again we are. The MGU-K and not the MGU-H can only generate when the driver activate the brake pedal. because we don't agree about it doesn't mean you are right and I am wrong, its just that we don't agree.

LOL. Your stubbornness concerning this point is truly entertaining. How many threads dedicated to SS will there be? What percentage of posts on this forum will be fruitless arguing with SS. Could the answer to these two questions be even more predictable than the constructors champion this year?

[hollus]

Oh yes back to that again we are. The MGU-K and not the MGU-H can only generate when the driver activate the brake pedal. because we don't agree about it doesn't mean you are right and I am wrong, its just that we don't agree.

LOL. Your stubbornness concerning this point is truly entertaining. How many threads dedicated to SS will there be? What percentage of posts on this forum will be fruitless arguing with SS. Could the answer to these two questions be even more predictable than the constructors champion this year?

“Your (mine) stubbornness concerning this point is truly entertaining” nzjrs. Your attention is drawn to the fact that for there to be a disagreement there have to be more than one person involved. Disagreeing is not only part and parcel of a forum but also heathy. and as I explained to PHillip, it is wrong for any side of the disagreements to assume that they are right and the other side is wrong.

[Jolle]

The simple answer is: yes it can and yes it does.

Lets say ICE power is 100% and K is 20%. so max output is 120%

if the driver asks 105% power, if could be 100%ICE and 5% K unit or 95% ICE and 10% K, etc etc.

If the diver/system is on full recharge and the driver asks 80% power, the system will put the ICE on 100% and the K-unit on -20% (harvesting)

having K without throttle is less likely, because there are not many applications for that. Limiting engine braking would be one, but can be done without energy loss by opening the throttle bodies. Maybe as a slipper clutch replacement? although I don't think cars need them and if they did, this could also be programmed into the throttlelbodies.

[saviour stivala]

“Can the MGU-K harvest or deploy under its own control?”.
I have no doubt that technically speaking it can be made too.
But I also have no doubt that whatever the rules say it or not it will not be allowed by said rules because it will be in total conflict with “the driver must drive the car alone and unaided”.
So in my opinion the said two functions of the MGU-K (Deploy and generate). Deploying is a function of driver accelerator pedal activation and generating is a function of the driver brake pedal activation.
A note:- percentages and or levels of deployment or generating as well as the percentage/level of deployment as a mix of power unit total output have nothing to do with what makes it function/what activates it, that percentage/level is mapped as a mode and selectable from on the steering wheel by the driver.

[dans79]

“Can the MGU-K harvest or deploy under its own control?”.
I have no doubt that technically speaking it can be made too.
But I also have no doubt that whatever the rules say it or not it will not be allowed by said rules because it will be in total conflict with “the driver must drive the car alone and unaided”.
So in my opinion the said two functions of the MGU-K (Deploy and generate). Deploying is a function of driver accelerator pedal activation and generating is a function of the driver brake pedal activation.
A note:- percentages and or levels of deployment or generating as well as the percentage/level of deployment as a mix of power unit total output have nothing to do with what makes it function/what activates it, that percentage/level is mapped as a mode and selectable from on the steering wheel by the driver.

Imo, there is a flaw in your logic. The way you are referencing “the driver must drive the car alone and unaided”, would make changing PU modes illegal. Switching power modes does a lot of things the driver could never do on their own.

[gruntguru]

“Can the MGU-K harvest or deploy under its own control?”.
I have no doubt that technically speaking it can be made too.
But I also have no doubt that whatever the rules say it or not it will not be allowed by said rules because it will be in total conflict with “the driver must drive the car alone and unaided”.
So in my opinion the said two functions of the MGU-K (Deploy and generate). Deploying is a function of driver accelerator pedal activation and generating is a function of the driver brake pedal activation.
A note:- percentages and or levels of deployment or generating as well as the percentage/level of deployment as a mix of power unit total output have nothing to do with what makes it function/what activates it, that percentage/level is mapped as a mode and selectable from on the steering wheel by the driver.

. . and as with most EV's these days, generating is a progressive thing that starts when accelerator % falls below a certain value and vehicle speed is high enough. In many cases, full generating is enabled by the time accelerator % has fallen to zero.

It is easy to determine if F1 teams are using a particular function or strategy:
1. Is there an advantage in using it?
2. Do the rules EXPLICITLY prohibit it?

If the answers are Yes and No, the teams are using it. This applies to engine throttles and MGUK activation. Both are controlled by the ECU. Provided the torque to the wheels is mapped to accelerator % as stipulated in the rules there is no problem - the car is being driven by the driver. Do not confuse "driving the car" and "managing the energy flows". The latter is mostly done by the ECU.

[saviour stivala]

The driver changing and or selecting power unit modes mapped into the ECU of which are approved by the FIA, from on the steering wheel is not illegal as it is his “driving the car alone and unaided’ by manipulating the steering wheel for steering the car, the accelerator pedal for accelerating and slowing the car and the brake pedal for stopping/slowing the car, the latter two functions of which makes the selected percentage/level of deployment/generating (by the MGU-K) from on the steering wheel happen.

[saviour stivala]

Pushing forward on this here most interesting subject/discussion the designed-in functioning of road going ‘EV’S and or electrified engine cars is useless and of no contribution to the subject at hand, in fact it contributes to confusing. This because these road going designed-in aims contrary to the formula one power unit design rules/regulations and or spirit of said rules and regulations, are concentrated at automating as much as possible functions away from dependency of driver control.
And now I will Abstain from expressing my opinion on this here most interesting subject for a while so as to give a chance to ‘some’ others to block me instead of me blocking them!.

[hollus]

It is easy to determine if F1 teams are using a particular function or strategy:
1. Is there an advantage in using it?
2. Do the rules EXPLICITLY prohibit it?

Number two hides an enormous black hole looming over any such discussion. There are plenty of Technical Directives, which are rules for all practical effects, that we do not have access to.
So it might well be that something is explicitly forbidden withuot us knowing.

[Dr. Acula]

Well, let me put this topic to rest.



That's not a place on the track where a driver would normally brake, but as we can see from the onboard, the tail light started to flash, which indicates the MGU-K is harvesting.
Yes, Rosberg was in a wrong mapping for the situation, but the fact that there is a mapping at all for harvesting under throttle clearly indicates how things are. I mean he didn't get a penalty for harvesting under throttle or did he?

[henry]

It is easy to determine if F1 teams are using a particular function or strategy:
1. Is there an advantage in using it?
2. Do the rules EXPLICITLY prohibit it?

Number two hides an enormous black hole looming over any such discussion. There are plenty of Technical Directives, which are rules for all practical effects, that we do not have access to.
So it might well be that something is explicitly forbidden withuot us knowing.

True. But if we see a piece of evidence that shows to the world, including the regulators, that a team is exploiting a feature and they continue to do so after that revelation we can reasonably assume that there is not an explicit regulation preventing the teams interpretation.

For instance @Dr Acula’s example. We see this all the time, harvest lights flashing and no indication on the onboard telemetries that drivers are touching the brakes. Or, a favourite of mine, the power unit traces in the magazine article on page 844 of the Honda power unit thread. They clearly show a spike change in the the MGU-K power on every upshift. Not to mention “extra harvest”.

No doubt there can be arguments that can be used against these. The driver may caress the brake pedal so softly that it doesn’t show on the telemetry, or the journalists just made stuff up, or the telemetry is faulty.

But then we can look at a learned paper:

Time-optimal Control of the Formula 1 Hybrid Electric Power Unit
A thesis submitted to attain the degree of DOCTOR OF SCIENCES of ETH Zu ̈rich
(Dr. Sc. ETH Zu ̈rich)
presented by
Mauro Rube ́n Ulisse Salazar Villalon
M. Sc. ETH in Mechanical Engineering

The author acknowledges people at Ferrari as mentors in this work.

On page 2 of this doctoral thesis we find,

If the driver is not requesting full power, the control system must deliver the amount of power requested by the driver, and the energy management system can only decide how to split it between the ICE and the MGU-K. Conversely, if the driver is requesting maximum power, the regulations allow the energy management system to decide the amount of propulsive power to provide and the split between the actuators.

I personally believe that there are 9 potential discrete modes of power operation of these power units knitting together the ICE, MGU-K, MGU-H and ES in various combinations. I call them discrete because typically control theory, for instance in the paper I reference above, suggests the optimal use method is bang-bang, operating each mode at its max each time it’s used. That doesn’t mean that there aren’t variations in what max is for each mode.

The Strategy modes the driver controls mix these together to suit the circuit and circumstances encountered. The paper above shows the mix can be variedwhile the car is in operation during a race. Parameters effecting each mode can also be altered by the driver using the multifunction menu system.

In short my answer to the question posed in the topic title is YES.