Hi-
I have made a preliminary design for an automotive compression tester and would like to run the idea past the Arduino experts on the forum for any feedback that they'd care to share. I'll try to be brief.
I need to sense the pressure from the combustion chamber during a compression test (fuel and ignition disabled). I want to be able to have a few input parameters for the varying engines that my tester will be applicable, display the results, provide data and possibly offer a probable scenario for various failure conditions.
I've reviewed the online tutorials for Arduino and seen a few example programs. I've also searched this forum for similar projects, from which I have gleaned some good information. I am a software engineer by day (old school C/C++) so I've already written the "sketch", based on what I've learned about Arduino thus far.
Here is the basic design, laid out in a linear fashion beginning at the plug hole:
Adaptor -> Pressure transducer -> Connector -> Unit casing (no connector for the cable) -> Arduino Uno R3 with data logger shield and display shield
I'm considering creating the ability to connect a smart phone for viewing of the data with an app, but don't have much experience with that, so might not go down that road. If anyone has any input regarding making the data available to a smart phone, I'd like to hear from you. I saw the SD stuff, but don't think that would be the way I'd wanna go.
Anyway, opinions? Also, I've been researching pressure transducers. Looking at a Honeywell unit that is 0-200 psi, 0.5 - 4.5 V output and that is powered with +5V. Any opinions there?
Finally, the display. I've reviewed the 2-line RGB LCD displays and they advertise that they have directional buttons plus a select. Then there's the 1.8" TFT with the same 5 buttons (which they are calling a "joystick") and the 2.8" TFT touch screen. The latter claim that they use less pins and less memory on the Arduino but I am not certain how difficult they are to program. I read that there are libraries available to draw lines and such for the TFT devices, but it kinda seems like I'd be getting much more complicated with one of those options, and they may end up being a time sink. But I don't have any experience with any of them, so I thought I'd ask. The 2-line LCD seems like it'd be the easiest. Any feedback here?
Thanks so much!
Jerry