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[on:]

Hello,

I am a student in biomedical engineering and I will be building a wireless ECG monitor.I would like to know if the following setup will do the trick:

I would like to use an arduino fio in combination with an Xbee module that will comminucate with an another XBee connected to my computer with an Xbee explorer serial to usb. I will process to signal and use an analog input of the Fio, sample my signal and then transmit it to the XBee plugged in my computer. Then, I will programme something in C/C++ to display the signal.

So, since I have never used any if these components, I would like to know if the programming of the Fio and the Xbee is relatively simple, if there is any documentation available, are there known problems I should be aware of,is the serial data easily retreivable from an Xbee, is the wireless programming of the Fio with the Xbee reliable, etc.

Thanks alot!

[Reply #1 on:]

I would like to know if the following setup will do the trick:

I would like to use an arduino fio in combination with an Xbee module that will comminucate with an another XBee connected to my computer with an Xbee explorer serial to usb.

This part is.

I will process to signal and use an analog input of the Fio, sample my signal

What kind of processing are you planning? What signal is being processed? Keep in mind that the ADC sampling rate is relatively slow.

and then transmit it to the XBee plugged in my computer.

As binary or ASCII data? If binary, that's two bytes. How will you synchronize the read operation, if a byte gets lost?

As ASCII data, that is a maximum of 4 chars plus some separator.

So, since I have never used any if these components, I would like to know if the programming of the Fio and the Xbee is relatively simple

Compared to what? For whom? The XBee doesn't need programming, any more than your car radio does. The Arduino does, but some people consider it simple. Others struggle.

are there known problems I should be aware of

Well, XBees come in two varieties - point to point and mesh network. One seems ideally suited for your purposes. One is overly complicated. Digi will tell you that the XBees don't need to be configured to work, but for optimum speed they do.

is the serial data easily retreivable from an Xbee

Yes. The XBee takes care of pushing the data to the Arduino, and into the serial buffer. All you have to do is read it. That is no different from using wires.

is the wireless programming of the Fio with the Xbee reliable

Couldn't tell you.

[Reply #2 on:]

Thank you for the response!

So here are the details:

My ECG signal will be amplified and filtered with an analog instrumentation amplifier with filters using op-amps. An ECG signal can be sampled at 100 hz since an ECG signal as a spectrum between 1 and 30 hz, so I believe the specs of the Fio is sufficient.

It will probably be binary, I will eventually convert the binary signal into voltage to display the signal.

I have followed some classes in C and Matlab programming, so I believe I should be able to handle Arduino?

If the Xbees don't need specific programming, then that's good news. I would still like to use the mesh network XBee because the ECG is basically a node in a Body Area Network, so eventually a Mesh network would be interesting in the future. Is mesh network programming still complicated if there is only one node communicating to my computer?

Also, is there a way in the Arduino software to show the data I will receive from the Fio/Xbee in real-time (well, almost real-time)?

Thanks again

[Reply #3 on:]

Is mesh network programming still complicated if there is only one node communicating to my computer?

No. You would just designate that XBee as the coordinator. All other XBees talk, directly or indirectly, to it.

Also, is there a way in the Arduino software to show the data I will receive from the Fio/Xbee in real-time (well, almost real-time)?

No. The "Arduino software" is an editor, compiler, linker, and uploader. It includes a Serial Monitor application to see the data, as text, not graphics. Not that binary data as text will mean anything,

[Reply #4 on:]

Also, is there a way in the Arduino software to show the data I will receive from the Fio/Xbee in real-time (well, almost real-time)?

 no but you can use labview

[Reply #5 on:]

Thanks PaulS for this clarification!

CyrilAnthony, I will explore the Labview option, as I've seen some projects involving Xbees using Labview. I'll see if I can find a student version or something "free" on the net. Have you ever used Labview with an Xbee? If so, is the whole process easily configurable and relatively lag free? Is it possible to manipulate the data within Labview? For example, I will have to convert my binary data into voltage, just a simple proportion. Is this possible?

Thanks!