Toyota GR86, 86, FR-S and Subaru BRZ Forum & Owners Community - FT86CLUB - View Single Post - Opensource Flex-Fuel Ethanol Content Analyzer with Bluetooth

Fiskafan · 12-29-2014, 12:01 PM

Hi,

Updated 2014-12-30:

It now has a working Bluetooth output (see video).
If you want to add Bluetooth output to your existing Zeitronix Flex-Fuel/ECA (and not connecting the 0-5v output obviously).
Youtube video showing the general functionallity of this prototype
[ame]http://youtu.be/ePhWbsj9BZc[/ame]

Living in Sweden where we have access to E85 in almost all gas stations has got me thinking about buying myself a flex-fuel kit.

However, the Zeitronix stuff is quite expensive and coming from the RC world where there are DIY alternatives for all problems got me thinking if there wasn't a cheaper alternative for transforming the 50-150 HZ output from the ethanol sensor to 0-5V. The goal with this project is to produce a module that is plug-and-play to the same level as the Zeitronix ECA.

I started working on a converter that utilises an ATTINY85 to convert the input to a matching output. The code inside the ATTINY85 is written in Arduino and only contains a few lines. The code can be adjusted to be used with different Ethanol sensors (that outputs different HZ) if needed.

During the development i have been thinking multiple times about how complex i should build it. E.g, should it have a OLED for displaying Ethanol content? is Ethanol % really that interesting so it can justify a bulky display? should the display also display OBDII? maybe it should also utilise a GPS? and so on... My final decision has been to make the ECA a single purpose, small and cheap as possible and then maybe build a standalone unit that can display both the Ethanol Content and ODBII information later on if anyone (including my self) would be interested in this. There is already an interesting ODBII project (http://www.ft86club.com/forums/showthread.php?t=75181) that easily could be expanded for sensing the ethanol content from the sensor .

However, yesterday i noticed that Delicius Tuning has released a ECA that outputs the ethanol information over a Bluetooth serial link. This is something that is really easy to accomplish in the ATTINY so I remade the prototype so that it contains Bluetooth from the start. The android App can then display the Ethanol % and also display an alert if the fuel is contaminated since the Ethanol sensor outputs 190HZ in case of contaminated fuel.

Currently i have a working prototype built on a bread board. The next step is to produce a circuit board containing all the correct components and start testing it to see if its stable when powered from the noisy 12V in the car. The Power supply is a bit on the high-end side (taken from MegaSquirt). But this is made by purpose in order to filter spikes etc from damaging the ATTINY and in the end also protecting the expensive electronics in the car itself.

Things still in progress (2015-03-18:

Beta testing

The reason for me starting this thread is to see if anyone else would be interested in a cheaper alternative compared to the ECA:s that currently are out there on the market and what your suggestions would be around the external display/SmartPhone App.

Update 2015-03-18:
The board has been sent out to a few beta testers. Im waiting for their feedback. If no issues are found then i have a couple more that i can ship. If you are interested then please PM me.

12-29-2014, 12:01 PM	#1
Fiskafan Member Join Date: Dec 2014 Drives: Toyta GT86 Location: Sweden Posts: 11 Thanks: 0 Thanked 32 Times in 5 Posts Mentioned: 0 Post(s) Tagged: 0 Thread(s)	Opensource Flex-Fuel Ethanol Content Analyzer with Bluetooth Hi, Updated 2014-12-30: It now has a working Bluetooth output (see video). If you want to add Bluetooth output to your existing Zeitronix Flex-Fuel/ECA (and not connecting the 0-5v output obviously). Youtube video showing the general functionallity of this prototype [ame]http://youtu.be/ePhWbsj9BZc[/ame] Living in Sweden where we have access to E85 in almost all gas stations has got me thinking about buying myself a flex-fuel kit. However, the Zeitronix stuff is quite expensive and coming from the RC world where there are DIY alternatives for all problems got me thinking if there wasn't a cheaper alternative for transforming the 50-150 HZ output from the ethanol sensor to 0-5V. The goal with this project is to produce a module that is plug-and-play to the same level as the Zeitronix ECA. I started working on a converter that utilises an ATTINY85 to convert the input to a matching output. The code inside the ATTINY85 is written in Arduino and only contains a few lines. The code can be adjusted to be used with different Ethanol sensors (that outputs different HZ) if needed. During the development i have been thinking multiple times about how complex i should build it. E.g, should it have a OLED for displaying Ethanol content? is Ethanol % really that interesting so it can justify a bulky display? should the display also display OBDII? maybe it should also utilise a GPS? and so on... My final decision has been to make the ECA a single purpose, small and cheap as possible and then maybe build a standalone unit that can display both the Ethanol Content and ODBII information later on if anyone (including my self) would be interested in this. There is already an interesting ODBII project (http://www.ft86club.com/forums/showthread.php?t=75181) that easily could be expanded for sensing the ethanol content from the sensor . However, yesterday i noticed that Delicius Tuning has released a ECA that outputs the ethanol information over a Bluetooth serial link. This is something that is really easy to accomplish in the ATTINY so I remade the prototype so that it contains Bluetooth from the start. The android App can then display the Ethanol % and also display an alert if the fuel is contaminated since the Ethanol sensor outputs 190HZ in case of contaminated fuel. Currently i have a working prototype built on a bread board. The next step is to produce a circuit board containing all the correct components and start testing it to see if its stable when powered from the noisy 12V in the car. The Power supply is a bit on the high-end side (taken from MegaSquirt). But this is made by purpose in order to filter spikes etc from damaging the ATTINY and in the end also protecting the expensive electronics in the car itself. Things still in progress (2015-03-18: Beta testing The reason for me starting this thread is to see if anyone else would be interested in a cheaper alternative compared to the ECA:s that currently are out there on the market and what your suggestions would be around the external display/SmartPhone App. Update 2015-03-18: The board has been sent out to a few beta testers. Im waiting for their feedback. If no issues are found then i have a couple more that i can ship. If you are interested then please PM me. Attached Images Last edited by Fiskafan; 03-18-2015 at 03:20 PM. Reason: Added Bluetooth support. General Improvments.