Any interest in developing an open source fuel economy gauge/computer?

[Duffman]

My apologies for a small hijack of the thread, but I am looking for some advice that is highly topic related. I have been looking to get into microprogramer like devices for quite a while now to do projects like this. I have a degree in Mech Eng and have taken classes in Electronics (analog) and some limited programming. I am looking for a good book or some websites that can get me started. I am not totally oblivious to the subject but have a couple of questions already.

Are they all programmed in C or C+ or do they use other languages and how do you know which one? Or is it all done by a compiler/assembler program?
I see different types like PLC, PIC, AVR, what are the differences and are there others?
Are they all burned with the same devices or is it manufacturer specific.
Some setups look like more complete boards than just chips, what are the differences/advantages?

I’m sure there are other people reading this thread that are highly interested in it as well and have similar questions. Please reply in:

http://ecomodder.com/forum/showthrea...5670#post15670

so as to not further hijack this thread. Thanks

[Coyote X]

http://www.addall.com/New/compare.cg...itle=&state=AK

that book is cheaper if you look around it is still expensive though since it is used as a textbook.


Here is a schematic for interfacing an atmel to an lcd dsiplay. As you can see it is really easy and a old cut up computer ide drive cable can be used for it. It is really trivial to set up the lcd and button interface so whatever we pick it should be able to make it through v2 and beyond. The pot on the lcd is used for adjusting the contrast.

[dcb]

FYI, we have a discussion forum on sourceforge for OpenGauge
https://sourceforge.net/forum/forum.php?forum_id=801345

Should we lock this down and move it there?
or move this to DIY?
or move this to a sub forum in DIY?
or split the thread up here?
or??

[Duffman]

Thanks for the info CoyoteX
But that still leaves a few questions open, if I buy that book, is it just good for one family of microcontrollers? Are there differences as I asked in my original post. I was also trying to find something cheaper than $60. I should have started a new thread when I posted the question but I have now for any further replies:

http://ecomodder.com/forum/showthrea...5670#post15670

[diesel_john]

Originally Posted by dcb

So what do you think? Will it work with a liquid or can it be made to work with a liquid?

Will not work with a liquid, but will with air for relative MPG.
I believe this will work, once the engine is warmed up.(choke off)
think that if we know 13 pounds of air is going into the engine that we also know that about one pound of fuel is going in. And calibrate that over 1/2 tanks of gas with a given driver technic. And as long as the driver doesn't get totally abnormally wild and crazy (read stay out of fuel enrichment), we got a real good idea of instant fuel consumption, especially at steady state. Add a magnet on the drive shaft. and it is a relative MPG meter. since carbs are variable (seasonal change) the ability to see and teak the cal. number without starting the cal. completely over would be a benifit. the tank fillup number would always be the standard to cal. by, but the MAF would show sec. to sec. relative changes in economy.

if you can continue counting distance with the engine off, and mass flow when the vehicle is stopped, it would be even cooler.

[dcb]

FYI, I put a "plan" on the sourceforge discussion group, I'm thinking that we might want to get geekey with the geeks and do some of the discussion over there.

https://sourceforge.net/forum/messag...msg_id=4859237

FYI, Coyote and S2, I had an epifinay (SP?). We don't need to reinvent a protocol to talk to the palm, we should just use the elmscan protocol and maybe make up a few "pids" for injector duty cycle data. That way folks have the option of using existing elmscan software/devices to get basic vehicle information from pre-96 vehicles as well. The AT commands are in http://www.elmelectronics.com/DSheets/ELM323DS.pdf and I will be putting a sample serial "conversation" to exercise/test the palm with.

[MetroMPG]

Originally Posted by dcb

https://sourceforge.net/forum/messag...msg_id=4859237

Permission Denied: Access to this page is restricted (either to project members or to project administrators) and you do not meet the requirements to access this page. Please contact the administrator of this project for further assistance.

----

So, we'll now take all discussion of the technical side of the project to SF, yes?

(That requires the participants to create an account at SF, btw.)

I don't think we need to lock this thread, since some non-technical information may still crop up by non-participants. Probably I'll start a new thread to keep EM folks up to date with what's going on.

Also, I think EcoModder shoud get a new forum: "Instrumentation". With this project moving forward, I think the number of discussions on the topic is only going to rise. Also, it's an important enough topic in general to modding/driving that it deserves a raised profile anyway.

[Cowspots]

Hi Y'all,

Even non computer controlled carburetor cars can give accurate instant MPG readings. You will need a pulse-generating flow meter and a counter. Activate the counter when you pass a 1/10 mile marker and deactivate it when you pass the next on your test loop. Now get out your calculator and figure the cc of fuel consumed by pulses. Now you have the raw data that you need for mpg: fuel consumed and distance traveled (BTW: fuel temperature will affect fuel density).

If there is a tank return fuel line you need two meters and if you want instantaneous mpg you need a pulse for distance from the VSS or a hall-effect ring on the driveshaft. Then a programmable processor with three high speed counters, fuel temp probe and a display interface. Badda Bing $$ there goes your budget.

It just depends on how badly you want this information and what you will pay to achieve it.

To be honest, the best measure of average mpg per tankful is my wallet.

Cowspots

[diesel_john]

Originally Posted by Cowspots

Hi Y'all,

Even non computer controlled carburetor cars can give accurate instant MPG readings. You will need a pulse-generating flow meter and a counter. Activate the counter when you pass a 1/10 mile marker and deactivate it when you pass the next on your test loop. Now get out your calculator and figure the cc of fuel consumed by pulses. Now you have the raw data that you need for mpg: fuel consumed and distance traveled (BTW: fuel temperature will affect fuel density).

If there is a tank return fuel line you need two meters and if you want instantaneous mpg you need a pulse for distance from the VSS or a hall-effect ring on the driveshaft. Then a programmable processor with three high speed counters, fuel temp probe and a display interface. Badda Bing $$ there goes your budget.

It just depends on how badly you want this information and what you will pay to achieve it.

To be honest, the best measure of average mpg per tankful is my wallet.

Cowspots

The issue is that, the driver is able perfect technic if instant MPG is displayed.

we have been discussing the fuel meter approach in my other threads as well as other folks. So far i think a MAF from the salvage yard and dcb and companies signal processing ideas have the finanical advantage for a carb'd or preOBDII engine. This is only good for a relative economy, while driving under similiar conditions.

[Duffman]

Originally Posted by diesel_john

we have been discussing the fuel meter approach in my other threads as well as other folks. So far i think a MAF from the salvage yard and dcb and companies signal processing ideas have the finanical advantage for a carb'd or preOBDII engine. I don't know what's going on where you guys are, but around me here people are driving, towing, dragging, and hauling cars to the scrap yard and selling them for $200/ton. And the computer controlled vehicles go before the carb'd ones because they are too expensive to fix.

I definately think that the MAF approach is the easierst way to go and would work fine if the engine didnt deviate away from stoichiometric A/F ratio but I think that is a bad assumption. I think a carb is much more likely to have A/F ratio fluctuations than FI.