complex math and so???are skills
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From: Albuquerque NM - The Land of 8000ft DA
Originally Posted by joecar
So after you get the temp bias, you have to solve a tensor equation for the unknowns matrix, is this the basic gist of it...?
Ah... it must be nice to have MatLab... (...I don't qualify as a student, and neither does my Mrs... yet...).
Ah... it must be nice to have MatLab... (...I don't qualify as a student, and neither does my Mrs... yet...).
Here's some info on wiki on it
http://en.wikipedia.org/wiki/Tensor
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Joined: Sep 2004
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From: Stockbridge GA
I'm glad some of you guys understand this. I had to spend too much time at work to do my calculus homework back in school. I ended up auditing the class to keep from having an F on my record. BTW, thanks to all who are working on this.
i'm stuck on math, and i need to solve this:
a=x*(b+(c-b)*exp^(-k*x))
exp() is a function of raising the base of the natural log to some power.
please solve this for x in terms of k. the rest you can treat as a bunch of constants for now. and your reward will be..umm.. to be able to tune your car right, good enough?
a=x*(b+(c-b)*exp^(-k*x))
exp() is a function of raising the base of the natural log to some power.
please solve this for x in terms of k. the rest you can treat as a bunch of constants for now. and your reward will be..umm.. to be able to tune your car right, good enough?
Originally Posted by RedHardSupra
i'm stuck on math, and i need to solve this:
a=x*(b+(c-b)*exp^(-k*x))
exp() is a function of raising the base of the natural log to some power.
please solve this for x in terms of k. the rest you can treat as a bunch of constants for now. and your reward will be..umm.. to be able to tune your car right, good enough?
a=x*(b+(c-b)*exp^(-k*x))
exp() is a function of raising the base of the natural log to some power.
please solve this for x in terms of k. the rest you can treat as a bunch of constants for now. and your reward will be..umm.. to be able to tune your car right, good enough?
If I remember I'll let Mathcad solve it for you tomorrow. I'm pretty sure that equation can't be solved explicitly for x in terms of k because of the presence of x in both an exponential and linear term. I don't know what you're doing with that equation,.....but it looks like x would need to be solved for numerically.
Originally Posted by RedHardSupra
i'm stuck on math, and i need to solve this:
a=x*(b+(c-b)*exp^(-k*x))
exp() is a function of raising the base of the natural log to some power.
please solve this for x in terms of k. the rest you can treat as a bunch of constants for now. and your reward will be..umm.. to be able to tune your car right, good enough?
a=x*(b+(c-b)*exp^(-k*x))
exp() is a function of raising the base of the natural log to some power.
please solve this for x in terms of k. the rest you can treat as a bunch of constants for now. and your reward will be..umm.. to be able to tune your car right, good enough?
you've got an email.
Christian
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Verdad Gallardo 11 Second Club
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From: Albuquerque NM - The Land of 8000ft DA
Originally Posted by beast69camaro
I'm pretty sure that equation can't be solved explicitly for x in terms of k because of the presence of x in both an exponential and linear term. I don't know what you're doing with that equation,.....but it looks like x would need to be solved for numerically.
I get
K=ln((c-b)/(a/x-b))/x
Originally Posted by RedHardSupra
i'm stuck on math, and i need to solve this:
a=x*(b+(c-b)*exp^(-k*x))
exp() is a function of raising the base of the natural log to some power.
please solve this for x in terms of k. the rest you can treat as a bunch of constants for now.
a=x*(b+(c-b)*exp^(-k*x))
exp() is a function of raising the base of the natural log to some power.
please solve this for x in terms of k. the rest you can treat as a bunch of constants for now.
Did you get my email with the Excel attachment?
Does this solution about the equation works well enough?
This spreadsheet was done using Excel to generate a numerical solution.
On the equation side, I can give you the solution in Matlab code as well, if that would help out more...working on it.
Christian
Last edited by miami993c297; Jun 1, 2007 at 08:17 PM.
Ok folks, I think I got the math for figuring out the BIAS table, which seems to be a major source of imprecision. I think that's one of the 'hidden variables' we didn't account for before at all, thus lack of 'convergence' of VE tuning. This is only a first step to a whole new way universal way of tuning that i've been working on for a while.
I hope you're not afraid of differencial equations, physics, and linear algebra, cause in 5 pages i got it all
http://www.marcintology.com/tuning/T...reModeling.doc
this is an early version, written mostly past 2am, so there's bound to be some wrong **** in there, so please let me know. More to come later, must graduate first.
I hope you're not afraid of differencial equations, physics, and linear algebra, cause in 5 pages i got it all
http://www.marcintology.com/tuning/T...reModeling.doc
this is an early version, written mostly past 2am, so there's bound to be some wrong **** in there, so please let me know. More to come later, must graduate first.
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Originally Posted by RedHardSupra
Ok folks, I think I got the math for figuring out the BIAS table, which seems to be a major source of imprecision. I think that's one of the 'hidden variables' we didn't account for before at all, thus lack of 'convergence' of VE tuning. This is only a first step to a whole new way universal way of tuning that i've been working on for a while.
I hope you're not afraid of differencial equations, physics, and linear algebra, cause in 5 pages i got it all
http://www.marcintology.com/tuning/T...reModeling.doc
this is an early version, written mostly past 2am, so there's bound to be some wrong **** in there, so please let me know. More to come later, must graduate first.
I hope you're not afraid of differencial equations, physics, and linear algebra, cause in 5 pages i got it all
http://www.marcintology.com/tuning/T...reModeling.doc
this is an early version, written mostly past 2am, so there's bound to be some wrong **** in there, so please let me know. More to come later, must graduate first.
I need to sit down and read your blog. Also, Very impressive.
What's your thesis on??
Graduating with what degree?
My hats off to you........
blog's gonna get updated once proof of concepts get tested and automated until your grandma is able to run through the process
i'm getting a masters in computer science/computer security, with thesis doing a vulnerability assessment of a secure neighbor discovery protocol in ipv6.
so any bugs yet? i'm still not sure of it's correctness in few spots.
i'm getting a masters in computer science/computer security, with thesis doing a vulnerability assessment of a secure neighbor discovery protocol in ipv6.
so any bugs yet? i'm still not sure of it's correctness in few spots.
This is what I got from that paper:
Using wideband and and fuel mass you can get Airmass. Using airmass, MAP, and VE you can figure out what the PCM is calculating for Temp. Then once you know what the pcm has calculated, you can solve for r. Is that right? So my question is, are you trying to find out what the pcm is using for r, or are you trying to find what value you're going to program into the pcm for your tune?
Using wideband and and fuel mass you can get Airmass. Using airmass, MAP, and VE you can figure out what the PCM is calculating for Temp. Then once you know what the pcm has calculated, you can solve for r. Is that right? So my question is, are you trying to find out what the pcm is using for r, or are you trying to find what value you're going to program into the pcm for your tune?
pmack: r is just a calibration. i want to tweak it in such a way that the calculations from the air side (the one with gmve in it) and the ones from fuel side (afr*ifr*ipw) agree. once we know r and somehow manage to translate it to corresponding MAF values (since the BIAS table is on the MAF scale) then we can just use it as a constant and use it to tweak gmve values. but that's later, for starters we gotta figure out the constants. but you're right, it's totally not obvious (as in i dont have a clue yet how i'm gonna approach it) to create proper airflow vs bias from rpm vs r we have now.
bink: why do you say it's 240/rpm? wouldnt then 240/6000rpm=0.040 secs? last i checked we got 20msec window at 6000rpm. what did i miss?
bink: why do you say it's 240/rpm? wouldnt then 240/6000rpm=0.040 secs? last i checked we got 20msec window at 6000rpm. what did i miss?
Ok, I have a problem with the whole premise of your r calculation. It is circular. You are calculating r based on what you get for TEMPexpected. TEMPexpected was calculated based on IPW, which was calculated by the PCM based on cylinder airmass, which is based on TEMP, which is based on r.
Your error was that you set TEMPexpected=TEMPobserved. If that is the case, then instead of calculating an actual r, you are calculating what the pcm thinks r is.
Also, as far as the 240/rpm thing goes, the number you use is meaningless. r was derived empirically, and 240 is just a coefficient in front of r. It doesn't matter. All that matters is that e is raised to (constant * time). The time the air is exposed to heat is not equal to the time between intake valve events anyway.
Your error was that you set TEMPexpected=TEMPobserved. If that is the case, then instead of calculating an actual r, you are calculating what the pcm thinks r is.
Also, as far as the 240/rpm thing goes, the number you use is meaningless. r was derived empirically, and 240 is just a coefficient in front of r. It doesn't matter. All that matters is that e is raised to (constant * time). The time the air is exposed to heat is not equal to the time between intake valve events anyway.
Last edited by P Mack; Jun 5, 2007 at 07:32 PM.
of course it's circular, you got airflow that depends on temperature that depends on the amount of airflow that's the whole problem, and that's why differential equations start to show up (against my will )
yes, you are absolutely correct, we are not calculating actual r, we're just getting r to do what pcm it should do. for now it's a iterative method, just like the old ve tuning, gotta do it few times. however this time it should converge better. i do have another approach where i tune both r and ve at the same time, which is gonna be pretty much the way the e38/e67 stuff must be done, but that's pretty friggin involved. i got a spreadsheet with a very early idea how to do it if you want to take a look at it.
hmm...that rpm multiplier is kinda pointless, you're right, r is just going to 'absorb' it anyway...good thinking, this is exactly why i posted this early stuff, this **** is entirely too complex for my blonde self :/
the time the air is exposed to heat is kinda important, that's why at lazy rpm/low airflow it's much more ECT biased. but you're right, what kind of relationship it is, i have no clue. any ideas what else influences it? if i have few potential suspects, i can figure out some weighing system and see which one influences it the most.
so far, great feedback. as a pimp said to his ho's: keep 'em coming!
that's the whole problem, and that's why differential equations start to show up (against my will ) yes, you are absolutely correct, we are not calculating actual r, we're just getting r to do what pcm it should do. for now it's a iterative method, just like the old ve tuning, gotta do it few times. however this time it should converge better. i do have another approach where i tune both r and ve at the same time, which is gonna be pretty much the way the e38/e67 stuff must be done, but that's pretty friggin involved. i got a spreadsheet with a very early idea how to do it if you want to take a look at it.
hmm...that rpm multiplier is kinda pointless, you're right, r is just going to 'absorb' it anyway...good thinking, this is exactly why i posted this early stuff, this **** is entirely too complex for my blonde self :/
the time the air is exposed to heat is kinda important, that's why at lazy rpm/low airflow it's much more ECT biased. but you're right, what kind of relationship it is, i have no clue. any ideas what else influences it? if i have few potential suspects, i can figure out some weighing system and see which one influences it the most.
so far, great feedback. as a pimp said to his ho's: keep 'em coming!
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Originally Posted by RedHardSupra
bink: why do you say it's 240/rpm? wouldnt then 240/6000rpm=0.040 secs? last i checked we got 20msec window at 6000rpm. what did i miss?
..
.
Carry on.