View unanswered posts | View active topics It is currently Mon Jun 17, 2019 5:48 pm



Reply to topic  [ 9 posts ] 
FreeEms Lite? 
Author Message
DIP8 - Involved

Joined: Mon Feb 18, 2019 4:54 pm
Posts: 27
So I've been digging through the threads (And there are a hell load) and one thing I see common is people trying to redesign Fred's project :P The common things I have noticed are:

Using a single line algorithm to control duration and advance of the injector pulse
Using more IC hardware to spare MCU
The ability to use whatever MCU they want

Could it be that people are asking for a super lightweight EMS code that is uber portable? That way they can stop crying about FreeEMS being so rigid. And it is Rigid, and that's ok. From what I've read, FreeEms is designed to be reliable and safe.
Just a simple thing that would take a base formula for fueling and self offset a constant until it has a perfect A/F then just multiply it by RPM, synchronized with the CPS. For multiple injectors, external circuitry could distribute the signal to the next injector until back to 0. It would be more hardware hands on and they could use their favorite dev board to run their brigs and stratton or GY6 without having to buy a big ECM kit. It could open new doors, I think, and give a lot of people what they have been begging for, especially for the noobies.

-Just a thought .


Thu Mar 07, 2019 3:27 pm
Profile
LQFP144 - On Top Of The Game
User avatar

Joined: Tue Jan 03, 2012 8:37 pm
Posts: 463
Location: Manhattan, KS. USA
Quote:
That way they can stop crying about FreeEMS being so rigid.


This is the best thing I've read in a tremendously long time, emphasis mine, and spot on about safety and reliability.

Subscribed.

_________________
FreeEMS vehicle #23: 2003 Toyota "Toxic" Tacoma
Build page: http://forum.diyefi.org/viewtopic.php?f=3&t=1635)


Thu Mar 07, 2019 5:17 pm
Profile
DIP8 - Involved

Joined: Mon Feb 18, 2019 4:54 pm
Posts: 27
Cool reaction B)
But I was thinking about my little CHP project which uses a single injector 3 cylinder Geo Metro engine. It turns a generator and creates heat, and that's all it's for. No need for a intensely engineered management scheme. Just something to fire an injector on time. However the Yamaha motor is getting a Jaguar ;)


Thu Mar 07, 2019 5:58 pm
Profile
Moderator
User avatar

Joined: Tue Jan 15, 2008 2:31 pm
Posts: 15271
Location: Home sweet home!
I once ran an engine with a squirty bottle of fuel and good judgement alone. If that's what you mean, then yeah, anything is possible. It's child's play to run any particular engine at all. It's man's work to engineer a system that is generic enough to run almost any engine using the very same codebase. Tinkering with some random MCU platform to run little engines is a great way to learn heaps :-)

_________________
DIYEFI.org - where Open Source means Open Source, and Free means Freedom
FreeEMS.org - the open source engine management system
FreeEMS dev diary and its comments thread and my turbo truck!
n00bs, do NOT PM or email tech questions! Use the forum!
The ever growing list of FreeEMS success stories!


Mon Mar 11, 2019 9:04 am
Profile WWW
DIP8 - Involved

Joined: Mon Feb 18, 2019 4:54 pm
Posts: 27
This makes me think of injector drivers. Everything I look at brings me right back to the LM1949 ic. I have one of these. Is it the only/best way? You want the output to look like this __|\--__ Has anyone here made a good schematic that works well and doesn't fry the injectors without an injector chip? What do the big manufacturers use? I heard Ford uses PWM to some sort of Darlington network. Maybe I'm just bored because there's still too much snow outside to get anything done and I'm itching to play with my toys.


Mon Mar 11, 2019 2:13 pm
Profile
Moderator
User avatar

Joined: Tue Jan 15, 2008 2:31 pm
Posts: 15271
Location: Home sweet home!
P&H is outdated tech. Virtually all current/modern port injection injectors are high impedance and require no such scheme, just a simple low RDS-on FET high speed switch.

_________________
DIYEFI.org - where Open Source means Open Source, and Free means Freedom
FreeEMS.org - the open source engine management system
FreeEMS dev diary and its comments thread and my turbo truck!
n00bs, do NOT PM or email tech questions! Use the forum!
The ever growing list of FreeEMS success stories!


Tue Mar 12, 2019 10:07 am
Profile WWW
DIP8 - Involved

Joined: Mon Feb 18, 2019 4:54 pm
Posts: 27
You actually got me thinking there. Sure would be nice to get away from fuel injectos that are 30 year old tech. I was just looking through Bosch's site (and on ebay to compare) their direct injection GDI injectors. Doesn't look like it would be all too difficult to drill a bung through a head. These injectors are pretty long and have a o-ring on both ends of the long shaft so it could, and would benefit, from penetrating a water jacket. I have an extra, unloved, cylinder head for my old Dodge 2.5. I may attempt this, if I feel the need to buy some of those injectors. I saw a set of 4 on Ebay for $15 (used of course). easy investment if you ask me. I should really watch my spending. I just bought a big linear stepper motor and a bunch of linear rail bearings and a really cool (and weird) optical shaft encoder from a guy doing electrical surplus (salvage I'm sure). It's made by Disc Instruments Inc and has 6 data wires and a ground strap. I can't find a datasheet anywhere. I tried to figure it out last night with not much luck. Any leads?


Fri Mar 22, 2019 5:53 am
Profile
Moderator
User avatar

Joined: Tue Jan 15, 2008 2:31 pm
Posts: 15271
Location: Home sweet home!
Direct injection is very different and requires tunable and precise timing and high pressures and very short pulse widths. FreeEMS isn't currently geared to that, though it could be changed that way, potentially.

_________________
DIYEFI.org - where Open Source means Open Source, and Free means Freedom
FreeEMS.org - the open source engine management system
FreeEMS dev diary and its comments thread and my turbo truck!
n00bs, do NOT PM or email tech questions! Use the forum!
The ever growing list of FreeEMS success stories!


Fri Mar 22, 2019 12:04 pm
Profile WWW
DIP8 - Involved

Joined: Mon Feb 18, 2019 4:54 pm
Posts: 27
Would an endeavor like that call for external logic? Because, to me, that's fun.


Fri Mar 22, 2019 2:55 pm
Profile
Display posts from previous:  Sort by  
Reply to topic   [ 9 posts ] 

Who is online

Users browsing this forum: No registered users and 1 guest


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:
Jump to:  
cron
Powered by phpBB® Forum Software © phpBB Group
Designed by ST Software for PTF. ColorizeIt.