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boroko
- 9th December 2014, 08:43
Hi all,
I have been looking for something to monitor automotive sensors that are NOT part of the OBD data.
Things like a transmission temp sensor, fuel pressure, EGT, Oil temp, and such.

For the OBDII data, there are things like the Torque App for android. Cool, but not enough for me.

There is a project that is just what I want, but it is on an Arduino. https://code.google.com/p/multidisplay/ It is a small community and it originates from Germany, so it would be quite a challenge for my skill set to completely convert.

They are even getting it to bluetooth to an android for the display. Perfect for my needs. If the thing were more accessible, I would buy it in a minute, even if it were a commercial product, if it were a reasonable price. My biggest problem is that there are too many projects on the table right now to take this on from scratch.

So, here is the question, Has anyone in the PIC community seen anything remotely comparable without buying a multi-thousand dollar setup from Stack? I will continue to pursue learning how they are doing it, and as I understand it, I will post it here if anyone else is interested.

Would love to hear what is out there.
Thanks
Bo

Amoque
- 9th December 2014, 12:21
It would be interesting to know what they are monitoring and how they are collecting the data. I suspect both of these are clues to a successful search for "similar" projects.

A scan of their webpage... granted, I hardly read any of it... looks like they're developing a display rather than new data. The reason I ask is that the sensors you mention ARE part of the OBD data - if your particular interface (scan tool?) decodes or displays them is a different story. Some "manufacturer's specific codes" do not decode for generic scan devices, but the information (everything from tire air pressure, to air bag status, to time and pressure applied to the brake pedal, to time and date of last service are part of the system, but unavailable without a specialized tool made available only to manufacturer's.

I work for the state inspection/ maintenance program and the amount of information your vehicle records makes the NSA drool.

Demon
- 9th December 2014, 16:18
I've always wanted to display my OBDII data.

Robert

Amoque
- 10th December 2014, 02:50
Robert, Google "ELM OBDII". For about 15 bucks you get a preprogrammed chip to read OBDII to serial...There are other systems that output Bluetooth to phone, laptop... It's all out there.

boroko
- 10th December 2014, 05:14
Hi all,
As far as the OBDII, the system is primarily for emissions and doesn't often monitor basic engine functions. To see what is covered with OBDII is already covered pretty well. For me, the Torque App on my my Android phone with the above mentioned Elm bluetooth adapter. What I'm trying to accomplish is read and display added sensors that are not part of the OBD system. In my case, I'm restoring a VW Vanagon Syncro that is getting a Subaru engine. These particular 4wd trannys are getting rare and expensive to rebuild and are originally designed for 90hp. Putting 175hp in them causes some extra heat that I'd like to monitor. The Subi motor needs some monitoring too. You could put half a dozen gauge pods everywhere, but I'd rather have a more elegant system.

Now, with all of that said, I can build the data collection side of it with some effort. In fact, I have already started. Truth is that if someone has already went down this path, I have restoring to do and could use the couple of month development time better.

What particularly intrigues me is the bluetooth integration and using a phone or tablet for the display. Having no experience in that area (the Android side) limits me there. Getting a clear picture of how their doing it from their site has been a challenge.

Just fishing. I will likely have to proceed on my own, but I was just hoping.

Mark

Archangel
- 10th December 2014, 08:15
Been a few examples here over the years, Acetronics did as I remember a tractor dash, SlotH did a superb GLCD snowmobile dash, but his links are all dead now, but skimask posted some code he whipped up and that code is in a thread linked to SlotH s dash link, some members here might still have that code "in Swedish" as it was written. looks like you just need to read a bunch of thermistors and thermocouples. You would have liked SlotH s GLCD
it was very cool.

boroko
- 10th December 2014, 10:53
I have seen casual references to Acetronics Tractor dash, but have never run across it. Time for some concentrated searching. I'll look for Skimask's answers too. btw: love your tagline.
Bo

Amoque
- 11th December 2014, 02:36
...As far as the OBDII, the system is primarily for emissions and doesn't often monitor basic engine functions...

I don't want to start an argument, but I am passionate about this. If you are looking for data... any data... from your gasoline powered vehicle, OBD is where to look. Start with OBDII.com and find your make and model; if it isn't there, check with the manufacturer. "P" (Powertrain) codes are emission related and, yes, include the transmission - shift points, engine RPM, and a host of transmission related parameters affect emissions. Why do newer cars have tire pressure low indicators? Because rolling friction affects mileage and lower mileage means higher emissions. Engine temperature affects fuel burn efficiency, so coolant temperature is measured; oxygen content of air is related to altitude, so barometric pressure is monitored... the list goes on. Other prefixes "B", "C", "U" and others designate other systems. Newer vehicles support "CAN" (Controller Area Network) where literally every system (airbags, electrical, transmission, fuel, exhaust, etc.) has it's own (at least one) controller running on the bus. Want to test this? Take off your gas cap and see how long it takes for the "MIL" (Malfunction Indicator Light) to come on. Why? Because gasoline fumes are high in hydrocarbons. And, where emission efficiency drops, cost takes over - imagine the cost of running individual wires for each light at the back of your vehicle - tail, brake, blinker... Now imagine running one signal wire to a microprocessor that activates those lights when signaled to do so - cheaper!

Do as you choose and believe what you like, but the OBD system, testing emissions, and working with mechanics to repair this equipment has been my job for the last 15 years. For the sake of those who come later looking for correct information I feel obligated to insist that OBDII is a very robust system - and expanding quickly - to include actively controlling the vehicle's braking, shifting, and steering among other things.

Sorry for the rant...

Archangel
- 11th December 2014, 05:42
I feel obligated to insist that OBDII is a very robust system - and expanding quickly - to include actively controlling the vehicle's braking, shifting, and steering among other things.

Sorry for the rant...
Very Robust, and expanding quickly. That is true, But, big big but, what year is this van? What was the state of OBD for that year? What was available and how much of the info was pro priority at that time? I think Bo is trying to avoid spending huge money and spending massive amount of time getting some basic info to his dash + Subaru != VW per Se in terms of "system". I have Snap-on mt2500 with software for my old cars, but compared to say a Ford Star tester, it's a toy, gets generic codes, reads some sensors, but for the other functions, no dice. So as I see it, you're both correct. . . and no I don't work on cars anymore, but I get where you are coming from.

So Bo, what year is the VW and the Subaru ?

BTW Skimask did an OBDII pic reader he was pretty darned proud of, posted it on YouTube looked pretty busy too, I'll try to find it.
https://www.youtube.com/watch?v=Nzd_ydoEGUk

boroko
- 11th December 2014, 06:23
Amoque, let me expand your perceptions just a bit.
I understand the need for CANBUS, OBDII, and all the benefits that they bring. And I understand that it has developed into a robust system and allows for major troubleshooting. Before you shoot holes in my thread, understand that not everyone's needs are the same. Feel free to look up an '90 Audi V8Q and tell me how much OBDII info is available. It is the older system that blinks out codes. How about a '98 Subaru Legacy, can you tell me the PID for the oil pressure and temperature? Or how about a '87 VW Vanagon? it doesn't even have OBD, let alone give me the tranny lube temperature. EGT is another parameter that is helpful that I haven't seen. Or a race car, or a tractor, or a generator set...

Bottom line is this, I would like to monitor a number of things that are not available through On Board Diagnostics on the vehicles that I own. For that, I would like to augment what info is available through OBDII without having a dash full of gauges that make my vehicle look like the inside of the Millennium Falcom. Any help to that end would be useful. As it appears to be something that few others have interest in, so I will continue to pursue it on my own. If I am successful, I will likely share it here. The move to an existing device as the display is also intriguing, thus the interest in sending it wirelessly to an Android App. I'd like to stay with PIC's, but what I have seen is on Arduino, and I am completely clueless on C or Java for the Android. Not to mention that there are a small number of people working on the previously mentioned MuntiDisplay, and they are mostly German. Anyway, thanks for the input, and when I start driving a 2015 Mercedes, I wont have as much need for this. Until then...

Bo

boroko
- 11th December 2014, 07:29
Archangel, thanks for the video. Wow, Skimask, what a project! And it is pretty cool to "meet" you. Its interesting that our perceptions of someone are usually greatly different than reality.
Bo

Demon
- 11th December 2014, 11:59
As far as the OBDII, the system is primarily for emissions and doesn't often monitor basic engine functions for older models..

There, fixed it for you.

Robert
:-)

boroko
- 11th December 2014, 12:15
Thank you. I stand corrected

Amoque
- 11th December 2014, 12:34
You are correct, Boroko, in my zeal to define how I see the system I have not adequately accounted your specific needs. Only vehicles 1996 and newer are OBDII equipped and, sadly, the '96 Subaru was improperly implemented and so still we offer an alternate test for that vehicle. I am anxious to help however. Here (http://www.obd-codes.com/trouble_codes/subaru/subaru-obdii-obd2-codes.php)is a list of the "P" codes available from that vehicle.

I would suggest that if there is a sensor it is being monitored by something (if there is no indicator in OBD or no gauge on the dash... I suspect there is no sensor) and it is likely (to my limited electronics experience) outputting variable voltage - to be read by ADC through a voltage divider, variable current - can be modified to be read by ADC, or a PWM output. I have used "Frequency to Voltage" chips with success - or perhaps the PBP functions of COUNT or PULSIN will be adequate. Once you are able to capture the signal (either from an existing sensor or one installed by you - while only 2015 Subaru may come with the sensor, it might be added...), Let the PIC condition the signal, then output to Android with one of the serial Bluetooth links. There are some pretty good "BASIC" programming apps for Android that should, with some study, allow the development of a display.

I suspect you have come to this same conclusion and are looking for a template, so as not to have to reinvent the wheel. Alas, I do not know of one; however, for a limited number of channels this project might require a reasonable amount of effort and, if the Bluetooth is eliminated, seems almost trivial once the sensors are located or installed. I am using several "analog" voltmeter gauges, driven by I2C DAC's - with custom background templates - they look quite nice and, such gauges are traditional in vehicles, even those without OBDII ;) .

Whatever you decide, I wish you the best of luck and stand willing to help in any way I can.

J. Mark Wolf
- 11th December 2014, 20:09
I started a project some time ago with the following features.

1. Battery voltage monitoring
2. 4 EGT thermocouple channels
3. 4 CHT thermocouple channels
4. Electric water pump current monitoring
5. Water temp
6. Oil temp
7. Charge Air temp
8. O2 sensor via serial port
9. Manifold pressure
10. Barometric sensor
11. Tachometers
12. Log data to a compact flash card
13. Graphic LCD output via serial port (Text and bar graphs)

Software is 80-90% complete but written in Proton syntax. Would be a relatively simple port to PICBasic.

Circuit board is complete.

Project was designed for an aircraft application, but the project went away.

PM me. We'll talk.

Tobias
- 12th December 2014, 21:03
I have an agriculture Android based electric motor controller that I use Bluetooth to communicate with the PIC chip(s)

I use B4A (basic for android) It is great.

Example screen shots
http://www.grahamelectricplanter.com/gc/

boroko
- 13th December 2014, 12:56
That looks quite nice. thanks for letting me know about it.
bo