MPGuino release one workspace

[MetroMPG]

Wow!! That's a slick build.

Should we have a unique "Success! MPGuino built!" thread where people who get to this stage can report in?

[cmags]

Thanks! I thought that's what the enclosures section of the wiki was for, but if we want a thread, I've got no problem photo-whoring out my hard work...

[jmilk]

Ok, I've been reading many of the pages on here. I like the idea -- I had a similar one before even reading this thread, and had the arduino in mind as well. My initial thought was to tap into my car's "trip computer" as that necessarily has all the fuel-usage and vehicle speed info available. The thing it's missing is the "immediate" mpg display -- it only has avg mpg, which gets to be relatively useless about half-way through a tank. I would also REALLY like to log average mpg per driver.

So I cracked open the overhead console and found that the trip computer has all of four connectors -- power supply and two for data. I'm 95% certain that it's the car's CANbus interface, which broadcasts vss, fuel, throttle position, etc.

Considering that CANbus (and some variations) are avaiable on the OBDII connector, why don't we just tap into that interface? The values are calibrated and should prove sufficiently accurate. Additionally, there's a line of AVR chips with build-in CANbus interfaces out there, and the prices are within the range of the ATmega168.

Any takers?

[dcb]

I'm sure you will find it, but the obd discussion is here:
http://ecomodder.com/forum/showthrea...auge-2702.html

[jmilk]

Originally Posted by dcb

I'm sure you will find it, but the obd discussion is here:
http://ecomodder.com/forum/showthrea...auge-2702.html

I should be slightly embarassed now. That's what I get for googling CAN and OBDII. See you there with my collected wisdom.

[ptsmith24]

I ordered a completed arduino board and LCD screen from nkelectronics (i believe that's the one linked to from post 1 in this thread.

How long did it take to get parts from NK? Once those parts get here, I will be getting the other misc. resistors/etc., an enclosure, and a quick disconnect. I believe the disconnect was suggested in another thread, but should still work for this setup.

[wagonman76]

Originally Posted by MetroMPG

Wow!! That's a slick build.

Yes, very nice build. I really like it. Whered you get the pushbuttons and how do they work? I had really thought about using some like that for mine, but the ones from Radioshack are really crummy, Ive used them before. Yours look much better quality.

[cmags]

Originally Posted by wagonman76

Yes, very nice build. I really like it. Whered you get the pushbuttons and how do they work? I had really thought about using some like that for mine, but the ones from Radioshack are really crummy, Ive used them before. Yours look much better quality.

Thanks again. Just your basic momentary normally-open push button switch:



I thought they were the same thing as at Radioshack, but I've never bought them there. Most recently, I bought some at http://futurlec.com, though my order got a bit mixed up and I got half momentary switches and half latching. I had plenty of spares though - was just replenishing my supply to bulk up an order. I also like to use these types of switches for various projects:



They're not tactile-switch tiny, but they're easy to work with and small enough for most applications (especially automotive electronics)....

[wagonman76]

Hmm ok. Maybe its just the lighting, yours look like they have chrome shafts with black heads. The ones I bought before had a really hard time of consistently getting continuity when you press them, you had to wiggle the button around sometimes to get a connection and I figured theres no way Id get multiples to press precisely at once. But its been quite a few years, maybe they make them better now.

[dcb]

I cringed at the signal those buttons would make too tactiles are pretty crisp and used everywhere these days (along with the soft switch matrix thingies)