Staged extra Injector control + other goodies design. Input wanted

[Joryn]

Quote:

Originally Posted by Aries_Turbo sweet, just ordered some sensors.

Ahhh, nothing quite as sweet as free parts in the mail

I'm going to see if I can't get some breadboarding done tonight so wish me luck on that. Hopefully by the end of the weekend I'll have some basic functionality built into my microcontroller. Start small, get big and always KISS.

I'll keep posting my progress (if there is any heh)

[Aries_Turbo]

hehe yup.

free parts rock.

Now I gotta figure out what to do with them lol. I havent touched a microprocesor in YEARS. maybe ill cobble together an analog setup that drives a PWM circuit to drive a fuel pump. who knows...

Brian

[Joryn]

Quote:

Originally Posted by Aries_Turbo hehe yup. free parts rock. Now I gotta figure out what to do with them lol. I havent touched a microprocesor in YEARS. maybe ill cobble together an analog setup that drives a PWM circuit to drive a fuel pump. who knows... Brian

I was actually wondering that myself. Do you think you can safely PWM a fuel pump without it wearing out extremely fast? I was thinking it might not be so bad cuz the only time it would be on would be under high boost levels so that might make it a little more durable, but who here has tried controlling pressure/flow by PWM'n a fuel pump? Sounds like a fun job hehe. Hurry up and build somethign so we can find out brian!

As a side note, if you're interested in getting back into a micro approach, I'd be more then willing to get you somewhat familiar with their use. The truth is that I haven't done any programming myself since my 4th year design project last year and so I'll be relearning a bunch as well.

The nice thing about the microcontroller's that I'm using is that, unlike microprocessors, they come with built in RAM, EEPROM, ADC, oscillator, all sorts of goodies that make them Very easy to implement in hardware. they are just slower then processors, but for our application I think we are fine. Let me know if you (or anyone for that matter) is interested on doing some parallel designing on this.

[90TurboVan]

I was planning on using a parallel port of my controller to drive a Darlington array or something. Pretty much whatever I can find laying around. Most likely, I would just mount a standard injector somewhere directly in front of the throttle plate and fuel it from a separate tank with regular fuel or possibly high octane stuff like someone else suggested on this thread.

As for PWMing a fuel pump, why not just rig up a stock fuel regulator and return instead of regulating it through PWM?

As a side note, would anyone on here be familiar with driving LCD screens? I have several mono and color ones that I would like to get working along with this project at some point, but I haven't gotten any of them to display anything.

[Joryn]

Interesting setup you have there 90TurboVan. You'll have to let us know how it works out in the end.

As for PWM'n the fuel pump the main reason would be that you could have an electronically controllable fuel pressure/flow source. On an alcohol misting setup having a pump where you just increase the pressure by increasing the duty cycle would be great for tuning. Most misters are rated at X flow at Y pressure so it would be pretty handy for something like that.

I imagine you would have to ensure that your pressure doesn't go too low or you won't have proper atomization of the fuel but other then that the sky's the limit.

As for driving LCD screens, I've worked with numerical LED's and what not mostly, not too much experience with LCD screens. Do you have a datasheet for hte screens you have?? I might be able to help you figure out how to use them.

[90TurboVan]

I'm not too familiar with misters and the like, but I can see now why PWM would be better for that.

I actually just got one of my lcd's working as I am writing this. I just needed to drive it a little faster, the 386 laptop i'm experimenting with is just a touch too slow. If you want to take a look at the datasheet, here it is. http://home.nikocity.de/woe/lcd/lm24010.pdf

[Joryn]

It's kinda strange that a 386 wouldn't be able to drive that lcd fast enough. most of these things run off of microproc's/microcontrollers. Well regardless you got it working so that's good.

This past weekend I was supposed to get my microcontroller basic programmed and running but my programmer wasn't working right so that was a no go. have it all setup but a micro with no code on it...well it's just a perty black rectangle heh. Hopefully within the next few days I'll get that cracking.

[DblTrbl]

Quote:

Originally Posted by Joryn It's kinda strange that a 386 wouldn't be able to drive that lcd fast enough. most of these things run off of microproc's/microcontrollers. Well regardless you got it working so that's good. This past weekend I was supposed to get my microcontroller basic programmed and running but my programmer wasn't working right so that was a no go. have it all setup but a micro with no code on it...well it's just a perty black rectangle heh. Hopefully within the next few days I'll get that cracking.

Depends if the 386 has the overhead of an OS.

An old 8 bit microprocessor usually has enough cycles to do almost anything in our cars.

Which family of microcontrollers are you using. I have the basic for the Intel 8051 family if you need it.

[Joryn]

Quote:

Originally Posted by DblTrbl Depends if the 386 has the overhead of an OS. An old 8 bit microprocessor usually has enough cycles to do almost anything in our cars. Which family of microcontrollers are you using. I have the basic for the Intel 8051 family if you need it.

I'm using the Microchip Pic line of microcontrollers, specifically the pic16LF877A for the initial prototyping. I'm hoping to switch to one with a larger EEPROM for table storage (ie: approx 1024bytes) but for now this will do.

You're right about the 386 though Carl. If the processor is really bogged down it would have difficulty driving something like that through a parallel port(which Ithink is what 90turbovan is doing).

What do you think about the PWM of a fuel pump idea Carl? Is there potentially a better way to electonically control pressure for misters or something like that?

[90TurboVan]

The only reason the 386 wasn't fast enough is that I'm running a completely unoptimized assembly program in dos. And yes, I am using the parallel port. They're so much fun and so easy to use, why not?

[Aries_Turbo]

Yeah I would LOVE to learn to use the PIC series of chips... Only problem, time and the fact that Im an extremely hands on learner that needs a walkthrough the first time... after a few times of me doing something, im basically a pro. Lemme know what you had in mind... we could do a Instant messenger with some webcams or pics of what we are doing to help communicate what we learned. lemme know if that sounds like something that you would want to do. I'll have to get Frank to check out this thread cause Im sure he'd want in too.

Brian

Quote:

Originally Posted by Joryn I was actually wondering that myself. Do you think you can safely PWM a fuel pump without it wearing out extremely fast? I was thinking it might not be so bad cuz the only time it would be on would be under high boost levels so that might make it a little more durable, but who here has tried controlling pressure/flow by PWM'n a fuel pump? Sounds like a fun job hehe. Hurry up and build somethign so we can find out brian! As a side note, if you're interested in getting back into a micro approach, I'd be more then willing to get you somewhat familiar with their use. The truth is that I haven't done any programming myself since my 4th year design project last year and so I'll be relearning a bunch as well. The nice thing about the microcontroller's that I'm using is that, unlike microprocessors, they come with built in RAM, EEPROM, ADC, oscillator, all sorts of goodies that make them Very easy to implement in hardware. they are just slower then processors, but for our application I think we are fine. Let me know if you (or anyone for that matter) is interested on doing some parallel designing on this.

[Frank]

Why pulse width a pump when you could pulse width a solenoid to bleed off pressure and flow and setup the return back to the container of fluid. I think it would be more feasable. All you have to do is setup a table of PWs to pressure for the calculations in the PIC. Attach a mechanical gauge to the setup, vary the pulse width to build that table. That way it is versatile for various setups. Just a thought as I think it is easier.


Frank

[Frank]

Plus a solenoid with a simple flyback circuit on it would require less power and transistor setup that a pump.


Frank

[Frank]

Dang, ideas after ideas. To make it easy a versatile, you could do something really cool for programing it... assuming this about a 5th injector or alky controller. (havent read enough of the thread recently.)

If you were to put the following items on the circuit, it would be externally programable. An 7seg display, Potentiometer, and a push button. Use the push button to select the following items - pressure/pwm table, boost pressure for on time (assuming i know what this controller is for ), and the flow rate of the misters (as a system whole). The 7seg display will flash in much the same way the engine check light does for the system codes for some of the items, except displaying a number. In addition, the pressure/pwm table would have set pressures hard programmed that you would set a PW to. So let me run thru setting up this controller....

1. Hold the pushbutton down until the 7seg does a '1 1'. Adjust the potentiometer until you get a 3 digit flash of the mister in a XX.X format. Say it is 30.0lb/hr at 40psi. You then adjust the pot until it flashes '3 0 0'. Then tap the button, and do the same for pressure and it flashes '4 0' since this would be in a XX format.
2. Hold the pushbotton down until the 7seg does a '2 1'. Adjust the potentiometer until you get the appropriate pressure on your gauge that corrilates to the hard programmed pressure in the 1st row of the table. This is represented by the 1 in '2 1' at the beginning of this step. Press the button to lock in the PW you just achieved for the given pressure, the 7seg then displays a '2 2' for the second position which is some pressure. You can then hold it in to move on to the other settings if you want.
3. Then hold the pushbutton until you see a '3 1' for to set a on boost pressure for the system much in the same way for step 1.


Just some thoughts.


Frank

[Mötörhead]

..."If you were to put sensors on the front wheels and back wheels for speed, you could have the controller effectivly learn the best boost "curve" to eliminate wheelspin"...

I have thought about this idea, but with no electronics background much beyond changing batteries in my flashlight, I was looking at stuff already on the cars. What about using the pulses from a rear anti-stop sensor to close a solenoid or to gradually open a stepper valve like they use for profec mbc's? Anti-stop processors are already available...there's also the signal from the speed sensor that may be of use in something like this...

Maybe you guys have all looked at this stuff, but I thought I'd throw something out there to help contribute to the collective or jiggle a few new thoughts loose...

I'll just carry on now as if I were normal...