hello

FreeEMS topics that aren't specific to hardware development or firmware development.
NinjaRider
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Re: hello

Post by NinjaRider »

the goal is to go camless, using analog solenoids.

and i did google it. couldn't find anything on it imperticular, but they do exist. how they function is currently beyond me. i would think each pulse changes the rotational state based on a degree step til max angle then reverts. versus an actual solenoid that would either open or close as high current was applied.
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Fred
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Re: hello

Post by Fred »

analogue solenoids?

There are basically two types of ECU controlled idle valves:

PWM solenoid
Stepper motor

The former is easily handled
The latter requires some hardware and code

Actual solenoids, when PWMed, don't open and close because the PWM is too fast, they hold the position of the average current provided by the duty of the PWM wave form.

LOL @ Peter and http://duckduckgo.com which I'm only partly using, still need to setup my browsers and short cuts to make it the default... shame on me!

Fred.
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Fred
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Re: hello

Post by Fred »

In any case, you definitely do not want to use a DAC for that; DACs are not much use for us, really.
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NinjaRider
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Re: hello

Post by NinjaRider »

then it would be pwm. which is what i thought it was. show's what some people know. :?

there's got to be a way to accomplish it without using the mercedes design. what fun would diy be if anything were easy. must do some r&d.
Peter
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Re: hello

Post by Peter »

NinjaRider wrote:show's what some people know
You crack me up.
:-p
NinjaRider
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Re: hello

Post by NinjaRider »

may i ask why.
Peter
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Re: hello

Post by Peter »

NinjaRider wrote:may i ask why.
No, because this will just be a pointless argument, but you did reminded me of this :-)
Image
lol
:-p
NinjaRider
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Re: hello

Post by NinjaRider »

wow. you had to go find an image to show your thought. about the stepper solenoid i was just going off what i was told by someone on srtforums because i honestly wasn't sure what the hell kind of iac was used for my engine. which if it were up to me and i had the time to spending doing it. i would dispose of said iac and use a vaccum bipass much how the 2003 zx-6rr is setup.
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Fred
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Re: hello

Post by Fred »

Peter has a dry sense of humour, don't take him too seriously :-)

One question: What mercedes design?
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NinjaRider
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Re: hello

Post by NinjaRider »

camless head.

mercedes came up with some hard to explain contraption. basically they used a solenoid design to move the valves then measured the distance they moved through another device to make sure the ecm didn't move the valve to much. they were able to produce a functioning prototype that worked and worked well. i've been thinking about this concept myself for 3-4 years if not longer now. the mercedes design using the same short block design was able to produce +10% hp over the cam head comparison simulating the stock cam profile. being camless you can allow valve overlap at the low power band and reduce valve overlap to zero at the top producing even more power. something mercedes mentioned was the ability to remove reverse from the trans and use the camless design to dead stall the motor at low rpm and reverse spin the crank. meaning to me if i can do 200 in drive i can do near 200 in reverse. :twisted:

thus the reason to my question about using multiple dac's which thanks to google i kinda answered myself. i would just need 12 pins to act as the serial com to the dac's. depending on the solenoid design i make i might need an amp after the dac to boost the amp's the solenoids receive.
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