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Beginner Questions for a Data Logger


#1

As a preface:
I’m a mechanical engineer grad student, and this area isn’t my strong suit.

On to the meat and potatoes:
I’m working on a project where I’m collecting emissions/operating data from a truck. There are two analyzers that are measuring emissions data (one can save data to an sd card or can communicate via usb and the other can output either via usb or analog), two devices that use a CAN network to communicate (but have an adapter to convert it to usb), and some thermocouples and pressure sensors (which output an analog signal). Currently, we have a datalogger that is recording the analog signals (one of the analyzers and the temp. and press. sensors), the other analyzer is saving data to an sd card, and the CAN devices are recording on the computer through their own program. As you can see, this is a mess, and is almost impossible to sync up as the time stamp on each will differ.

I ran into a guy the other day and he referred me to look at the GHI boards because that’s what he has used in the past. I’ve read through the various products and documents on the site and I think that the EMX board is what I probably need. My problem is that I’m not very experienced in any of this and I’m not real sure where to start. I’ve read through the Beginner’s guide, but it doesn’t really help on choosing a board.

What I’m asking is, does it sound like an EMX board would do what I’m needing it to do? I’ve done some C++ programming, but, as i said before, this isn’t really my wheel house, and I’m not really sure where/how to start. Does this sound hopeless, and should I probably just give up? Or do you think that this is do-able? Thanks for any help you guys can give.


#2

We call it FEZ as it is Freakin Easy to use :slight_smile: We have had many users that come in and have no idea what they are doing and have accomplished a lot. Now, you are an engineer so it will even be easier for you.

EMX (FEZ Cobra) is a perfect place to get started. It is right in the middle, not too pricey and not too basic.


#3

The EMX board (or one of the associated Cobra expanders) would meet your needs from a hardware perspective, with the possible exception of ADC precision. Micro-Framework devices (particularly the GHI devices) are about as easy to deploy as anything you will find. Nonetheless, your project is still challenging, particularly given programming is not your key thing. The data-logging aspect is achievable via the SD file system. If you have to interface to non-standard USB devices, youll have to learn things that are best avoided. If youre looking to use Analogue (voltage) inputs, be aware that the EMX input range is 0 to 3.3 volts. The internal converter has 10 bit resolution (so 2^10 [1024] output codes), so each measurement step is 3.3/1024 ~ 3.2mV. If you need more precision, there are options, but they incur extra work/cost.
Ive just completed a data-logger/web-server project – programming is my main game. I know of no easier way of doing this than using a MFW device, but the effort is still substantial.