refresh951

Cool stuff Tom. I have everything here but have not touched it yet as I have been focused on baseline tuning my stroker motor. Should start working on the the data logger in the next week or so.

Tom M'Guinn

If you are going to use it to log data, you might also consider interfacing the Arduino with an encabulator (or if you have the amulite, trying to use it as a stand-alone encabulator!)...

David Floyd

He said "dingle arm"

refresh951

LOL

refresh951

Making progress on my data logger. Pretty fun stuff for sure. Second pic is a differential pressure sensor with a 0-5V output. Looking forward to getting pressure drop numbers at the intercooler, the maf, and throttle body.

Tom M'Guinn

Now you're talking -- looks like you're having fun and making progress!

I do think the Arduino (or a couple of them) could manage the whole motor, though it would take quite a bit of supporting circuitry -- injection drivers, ignition drivers, ISV driver, etc. -- and some fancy C++ programming...

refresh951

Made a ton of progress on my Arduino data logger today. This thing is amazing and a blast to work on! I should have several analog channels up and running this week. Starting to get the hang of the code. I successfully have pressure sensor data being written to the data shield SD card in time stamped intervals!

refresh951

It lives! Going to log some pressures tomorrow night. Then I have to put a simple circuit together to read the GM AIT thermisters.

Tom M'Guinn

Looking great! I vote for a wireless shield for some track-side telemetry! Something in this thread may be helpful as you work up the temp sensors.

http://reutterwerk.com/forums/showth...highlight=temp

At the risk (near certainty) of looking like an old guy who had to walk uphill in the snow to school both ways, here is my first microcontroller project from the 80's -- it's actually an 8051 like in the DME -- except all it could do was say "hello world"... The Arduino is infinitely more useful and accessible and not a minute too soon. Here's to progress...

refresh951

Lol, working on the code for the Arduino brought back memories of FORTRAN 77 in the late 80's. I remember working on the schools main frame in the middle of the night as you had to sign up for 1hr blocks and that was all I could get. An IBM line editor, what a disaster! I remember people having emotional break-downs at 3am because their "Hello World" program did not work.

Tom M'Guinn

The Arduino probably has more processing power than all those IBM's combined -- pretty incredible, especially for those who remember the days before personal computing.

My pictures didn't post, so here they are. Hardware from the 80's, with modern day dust on top...

Scott H

Nice work Shawn. I've been reading some of the Arduino tutorials in my spare time and it does seem relatively easy, even for someone with limited knowledge of coding. I've done some scripting and beginner Perl stuff back in High School but it's been close to 10 years since I've looked at that stuff. I'm going to order the starter kit and work through some of the sample projects.

And Rob, your car seems to have picked up a rash, you might want to get that looked at

refresh951

From RW: "I made up my own driver circuit from Radio Shack that I will detail in a new post. Bascially, just a 5 volt regulator with 2K resistors used as voltage dividers."

Tom - I am no EE but rather a gear head, lol. Any chance you could give me specific details on this as then I can then re-use much of your info? Maybe a simple schematic? TIA

Tom M'Guinn

It is indeed very simple. You just make a voltage divider out of a Radio Shack resistor (2k, 1/4 watt) and the temp sensor, and log the resulting voltage. Read up on voltage dividers here:

https://learn.sparkfun.com/tutorials...oltage-divider

As the resistance in the sensor changes, the voltage between the fixed value resistor and the sensor varies. So, for example, when the sensor reads 2k ohms, the voltage from this circuit will be (2k/4k)*5v = 2.5 volts. When the sensor reads 8k ohms, the voltage from this circuit will be (8k/10k)*5v = 4 volts. Knowing that, along with the resistance scale of the sensor, and you can use the Arduino to calculate temps based on the voltages it sees from this circuit. If that doesn't make sense, just let me know.

refresh951

Perfect! Thank you Tom!