Only $50 for a pair of RF modules, each Arduino-compatible, is a very good deal.
I hope you guys reach your goal.

Thanks for the tips! I've also now located some information about it in the online manual/documentation pertinent to my car.

Noted -- and does one have to hack something apart to get access to either of those modules? I guess I'm asking how I actually break in to this area of the car.

Generally speaking, where is the OBD / CAN Bus port/connector located in a car? Is it readily accessible, or does one have to break into potentially hazardous wiring territory within the car? (I'm not even sure if my car, or even most modern cars, have this kind of data provision.)

I tried looking in the manual, but perhaps I have got the terminology/idea wrong.

I've recently become interested in experimenting/learning more about this subject after having read about the CAN-Bus support on the Arduino Due.

Thank you for this! I'm getting started on CAN.

Simon, Yes, please do see what they can do to make the diagrams readable. Going by the previous editions, this book is absolute gold, and extremely readable. And the under $25 price on Amazon is affordable for students like me.
And @thewknd: Thanks for the link.

Seems you guys are already nearly half-way there -- wow, that's fast.

Simon, Regarding the other book (co-authored by you) "Practical Electronics for Inventors 3rd edition" -- when will this be released on Kindle/ebook format? Been looking forward to this new edition for a long time!

I searched on Amazon, but only hardcover is available: http://www.amazon.com/Practical-Electronics-Inventors-Third-Edition/dp/0071771336/ref=dp_ob_title_bk

Thanks for designing this; definitely could be of use to my projects.
The website's not loading though -- at least at this moment.

Robert, As the site (http://playground.arduino.cc) states, "This is the place to post and share your own code, circuit diagrams, tutorials, DIY instructions, tips and tricks, and after all the hard work, to show off your projects."

So I think your post more than qualifies, especially because, based on seeing your blog, you have a very clear, organized writing style!

I'm sure most of the community would back you up on that.

And, if you would make a tutorial regarding Arduino & SD covering the various aspects that you mentioned, it could become a much-needed accumulation/bible of all things data-logging-related for Arduino-users. If something like that exists, at least 25% of the SD-storage-related questions on this forum could probably be avoided

There are numerous questions coming up all the time regarding data logging, especially faster logging (you have seen the "Storage" section of the forum already). And one of the sadly missing things is that a lot of the knowledge from the forum answers is  never accumulated into a permanent page of wisdom that future users can refer to.

While a lot of the blogs on the Internet, e.g., Ladyada's site, cover basic hardware setup of Arduino-to-SDcard, however there is a big need for authoritative tutorials on the software side of SD logging.

Fat16lib's library of course has been an enormous step, and a tutorial like the one you want to write could be a very useful instructive contribution to lots of people.

I remember I spent nearly a few weeks in my early Arduino days to achieve faster logging than a few hundred points a second; of course, now the target has been extended further!

@giantsfan3: thanks
ok for the post, but can´t do it today. Maybe with a title like '[Info] Example measurement for high speed ADC & SD Card writing' and maybe asking interested folks what the would be interested in to be measured further.

I looked at playground -> storagy....am unsure if my post already qualifies for the playground olymp For example I didn´t add the info, which hardware I used, which SD card etc. So it´s no qualified measurement in the sense.

I´m wondering more if a kind of 'getting started with Ardiuno & SD' would help people more (After reading some of the topics in this forum....). Something along these lines
- Working example of setting up the hardware + simple sketch to basically test if it works in principle (people could also be asked to try this before posting questions ) ; could be complemented over time with 'proven SD cards'
- Basic steps to analyze issues (memory consumption, frequency/data volume of updates to/read from SD)
- Decision tree along some questions ( a) volume of data to be written (b) which frequency to you want to log with...). There will also be some ends in the decision tree that end in 'Do not use an arduino, better get a digital scope...')

Opinions?

@volshebnick, These enclosures look just fantastic! Kudos on having such a beautiful sense of design. Honestly, I'm surprised the price is so low.

Since you mentioned customizing enclosures, I want to ask: Can you customize enclosures on an as-needed basis for small changes like cutouts/holes or slightly longer along one axis? I'm talking about low quantities (1 to 10 enclosures). If you provide this service, what kind of price range will such custom enclosures be?

@Robert Getzner:
This is great. Thanks for the detailed analysis!
And I wish there was some wiki where information like this were made permanent (Perhaps the Arduino playground?).
Until then, could you please create a separate new thread/topic on the "Storage" section of the forum, and either link to, or copy and paste, the information from your webpage.
You could perhaps title the thread something generic enough (e.g., "SD card writing at high speed / sample rate") so that future searchers can find it easily.

Will do what I can on my social networks to help spread it!
It's a much-needed project, and was inspiring to read the background on what first motivated you to do this.

Also, have you considered submitting a summary to some tech blogs/blog authors? Early PR can help generate a lot pledges for crowd-sourcing projects, and for a project like this which practically everyone can relate to, people becoming aware of it on popular blogs might make all the difference.

Load cells can be pretty cheap -- what kind of precision are you looking for? e.g., what is the smallest difference in weight that you want to measure?

Alternatively, you can trigger the light to turn on only when the cat is on the road; for example, you can put a color sensor on the collar, facing down, and check what colors the sensor primarily sees. This would be a little crude, but if you take a series of measurements over a few seconds, then you can tell with certainty that the cat is on a road-like surface.