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Brake Score Calculation

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Does anyone know how the lifetime brake score is calculated?

Is it just an average?

A time-sensitive average? (like only the last 3 months of braking included)

A weighted average? (applied the brake for 10 seconds/X feet/etc and got a 99% as opposed to the quick stop 57% score)

 

I'm just curious as I've managed to increase mine from 97 to 98 after months of being at 97. I achieved this right before a trip to an unknown area and a few quick changing lights dropped me back down to a 97. After a week of my normal commute I was back up to 98 and have been there for 2 weeks now. I'm wondering if it's possible to climb up to 99, but I only see that happening if it's a weighted or time-sensitive average.

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Brake score seems to be calculated by taking the actual energy recovered divided by the potential energy available to be recovered. The Lifetime must just store the history of both and continue the calculation. In the black FFH we started out at 97% and then 98% over time and eventually got it up to 99% Lifetime when we did the PCM update around 16,000 miles and did a Lifetime reset. In the 3000 miles from the PCM update until we replaced it our brake score was 99%. It should have been 100% for awhile, but my first trip after doing the Lifetime reset I got only a 99% brake score because of heavy traffic and that set the tone. In the new white FFH I managed to keep a Lifetime Brake Score of 100% for a few weeks. I don't know that I'll ever get it back up to 100% though :( even though in 2500 miles of driving I can count on one had the trips with less than 100% brake score (4 trips @ 99% and 1 @ 98%), I don't think it'll ever get back to 100%.

 

Over time, it gets harder and harder to incrementally change that number because of the volume of data. The black car didn't turn from 98% to 99% until we had over 8000 miles. We had a brief period back down to 98% after our summer Canadian road trip because high brake scores are very hard to get on curvy mountain roads, but once we were back in the city we quickly got the Lifetime back up to 99% before doing the PCM update.

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It calculates based on speed. Since a car moving at a set speed weighing a set weight takes a set amount of energy to slow down, it uses those parameters to calculate how much energy has been captured. Since the car doesnt know how many people are in it, it just uses the empty curb weight, so you could gain more potential energy with more people in the car, so the 100% brake score can come up before you even come to a stop. I have seen that happen several times, 100% score while still traveling 10 MPH.

 

One thing that skews the score is if at anytime the service bakes are applied, even briefly. When done right the service brakes apply under 5 MPH to stop the car completely.

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Okay, two plausible answers from our Moderators, which answer is it?

:detective:

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Okay, two plausible answers from our Moderators, which answer is it?

:detective:

 

Both are essentially the same. More speed translates to more energy to recapture from the regen process.

 

Thanks guys, that makes perfect sense.

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This is likely proprietary software algorithms that Ford will not disclose similar to what was recently experienced in regards to the "learning bad habits" discussions. Unless someone has inside knowledge from the Ford software engineers, then it would seem that we are left only with interesting speculation and educated guesses.

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Ford has a lot of Patents for hybrid vehicle technology and many are listed on the internet.

I found several that discuss the Ford strategy for the capture and storage of energy when the vehicle is experiencing powertrain braking.

 

This is an example of a Ford Patent.

After reading through several I came to the conclusion that the Mod's answers are to the point, informative without excessive technical jargon and simple enough for me to understand.

Thanks guys.

Edited by GrySql

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Ford has a lot of Patents for hybrid vehicle technology and many are listed on the internet.

I found several that discuss the Ford strategy for the capture and storage of energy when the vehicle is experiencing powertrain braking.

 

This is an example of a Ford Patent.

After reading through several I came to the conclusion that the Mod's answers are to the point, informative without excessive technical jargon and simple enough for me to understand.

Thanks guys.

With this link in hand HB might not be going to bed tonight ;)

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Remember that what's patented isn't necessarily what the car does. Manufacturers will patents lots of ideas that they never use just to prevent their competition from reading their patents and figuring out how the cars work.

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Remember that what's patented isn't necessarily what the car does. Manufacturers will patents lots of ideas that they never use just to prevent their competition from reading their patents and figuring out how the cars work.

Sure, after reading a few of those I can see that, in general, your answers are all that are needed for the layman to understand the principles of it.

There are not many on this Forum working as hard as you are to get specific answers to this phenomenon of a car, and that requires a lot of time and discussion here.

Most of us appreciate it.

Edited by GrySql

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Sure, after reading a few of those I can see that, in general, your answers are all that are needed for the layman to understand the principles of it.

There are not many on this Forum working as hard as you are to get specific answers to this phenomenon of a car, and that requires a lot of time and discussion here.

Most of us appreciate it.

I just meant that just because Ford has a patent on something doesn't mean that what's described in the patent is what our cars do. On the C-Max Energi Forum there was a rather heated debate when one owner researched some Ford patents about Oil Maintenance Mode and wrote a long post stating as fact that the car operates as described in those patents. Other members pointed out that you can't assume that. One C-Max Energi owner is even a patent attorney who acknowledged that. Researching patents can help us understand things that we've already observed without fully understanding it. But I don't think that patents can be a starting point for research because we don't know what patents are in use in our cars.

 

It calculates based on speed. Since a car moving at a set speed weighing a set weight takes a set amount of energy to slow down, it uses those parameters to calculate how much energy has been captured. Since the car doesnt know how many people are in it, it just uses the empty curb weight, so you could gain more potential energy with more people in the car, so the 100% brake score can come up before you even come to a stop. I have seen that happen several times, 100% score while still traveling 10 MPH.

The brake score will appear once you are going slowly enough that regen is no longer active. I don't think that it has anything to do with the weight of the car.

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The brake score will appear once you are going slowly enough that regen is no longer active. I don't think that it has anything to do with the weight of the car.

I have weighted down the car a few times and have seen the brake score show up long before stopping while still going 10 MPH, while normal driving with just me, or with the wife I rarely ever see it pop up before stopping. . Thats what I based my theory on.

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I just meant that just because Ford has a patent on something doesn't mean that what's described in the patent is what our cars do. On the C-Max Energi Forum there was a rather heated debate when one owner researched some Ford patents about Oil Maintenance Mode and wrote a long post stating as fact that the car operates as described in those patents. Other members pointed out that you can't assume that. One C-Max Energi owner is even a patent attorney who acknowledged that. Researching patents can help us understand things that we've already observed without fully understanding it. But I don't think that patents can be a starting point for research because we don't know what patents are in use in our cars.

I was employed for 31+ years as a software engineer by a computer company that has led in US patent awards for over 20 years and in my experience what HB is saying here is accurate (at least in the case of my employer). The company aggressively motivated their engineers to write invention disclosures via the employee’s performance appraisal process and with lucrative financial incentives. Engineers were encouraged to write invention disclosures on any subject. It did not have to be related to the employee’s area of expertise, it did not have to be incorporated into the company’s products, and it did not have to be related to the company's products. Of the patents I participated in several were never deployed in a company product.

 

Patents are important to companies beyond the obvious patent protection of a product. They can be sold for large amounts of money and more importantly they are used as leverage in defending against lawsuits by competitors.

Edited by Texasota

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Sure, after reading a few of those I can see that, in general, your answers are all that are needed for the layman to understand the principles of it.

There are not many on this Forum working as hard as you are to get specific answers to this phenomenon of a car, and that requires a lot of time and discussion here.

Most of us appreciate it.

In the short time I have been here I’ve been soaking up information like a sponge from HB, acdii, grysql, b25nut, murphy, corncobs, hermans and many others. All of this information is helping me decide if a FFH is a good choice for me. Having never owned a hybrid this is a big decision and I view this forum and the members as a valuable resource and one that I appreciate very much.

 

Because I’m using this information to help with this decision I’m sensitive (perhaps overly so) to information presented as speculation/theories (which I enjoy as they make for intriguing and engaging discussions) as opposed to facts. HB's post above made it clear he was making an educated guess (speculation) on how the brake algorithms work. Acdii's posts, as above, frequently come across as definitive statements of fact. Both are theories with interesting ideas but I am reluctant to simply choose one or the other as the final statement of fact on how it works. I suspect it could be considerably more complex.

 

I appreciate that I likely come across as a cantankerous old curmudgeon.

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Well I guess we try to convince people that you can't go wrong buying a hybrid no matter how hard you try.

It's a very fun toy to have and trying to pick out pattern on how the car functions. For me that's what I do for a living trying to figure out the best solution or reverse engineering a piece of software to figure out what's wrong with it.

 

The brake score is such a tricky black box it's hard to figure out. Sometimes I think yeah now I know how it works and that's correct 9 out of 10 times but the 10th time it throws you a curveball. Like the other day a had a bunch of short notice stops with scores in the 70's - 80's. Even with a higher than average # of 100% I still don't understand why I got 99% brake score after the trip.

 

For me that's part of the fun owning and driving this car.

 

Btw happy belated birthday LIR ;) she even got a birthday card from my dealer with a $10 gift card.

Edited by corncobs

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In the short time I have been here I’ve been soaking up information like a sponge from HB, acdii, grysql, b25nut, murphy, corncobs, hermans and many others. All of this information is helping me decide if a FFH is a good choice for me. Having never owned a hybrid this is a big decision and I view this forum and the members as a valuable resource and one that I appreciate very much.

Many of us bought the '13 FFH without ever seeing one in person, I'd never owned a hybrid either. Ignorance is bliss.

I found this Forum after about one month of owning my FFH (Jan '13) and B25Nut, HB and acdii nursed me thru the beginning of enlightenment.

Fifteen months later there has been a lot of ground covered.

Back then the first thing I learned was to not take anything a Dealer said as gospel, I have since found a great Dealership that works 'with' me.

 

This forum has added a great deal of correct info to the FFH database though the good old fashioned heuristic approach and hard research.

The amount of very experienced, intelligent and energetic members makes this a special Forum for solving problems.

Without knowing Ford's secret sauce algorithms we can only do what is possible with the info we've learned and continue to learn.

Learning the principles of these cars creates better owners and drivers and we share the desire to help each other achieve this.

Having the Fusion Marketing Manager personally send me a nice Ford gift package for a job well done discovering a flaw in production is an example of our collective efforts.

 

There is no perfect car, it has to meet your needs, purpose and budget. After the 'early adopter' syndrome wore off I've come to realize what a great car this is.

There are 'Monday builds' and 'Friday builds', meaning some cars turn out better than others.

My FFH was a medium mpg achiever that is aging into a good mpg car, almost everything else on the car has worked correctly.

My plan is to drive it for a long time.

You ought to get one too, then theory will meet reality, they are nice cars to own.

 

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