Re: Small low-cost embedded board for model airplane


Paul Carpenter wrote:
On 23 Sep, in article
<1159077661.584590.144500@xxxxxxxxxxxxxxxxxxxxxxxxxxxx>
albertgoodwill@xxxxxxxxx "Albert Goodwill" wrote:
============
* ADC (Analog to Digital Converter)
13 channel (simultaneous sample hold is desirable)
16 bits resolution
it will be used to capture 1000 samples/ second
<snip>
I would have expected for these types of sensors a sampling rate of
10 to 20Hz per channel giving 130 to 260 samples per second.
Considering the nature of the sensors being slow response and the
application simultaneous sample and hold seems unnecessary.
<snip>

Following are the sensors to be connected to the embedded board
Sensors with analog outputs
* 3 axis accelerometers (0-5v or 0-3.3v analog outputs)
* 3 axis gyros (0-5v or 0-3.3v analog outputs)
* 3 axis magnetosensors (0-5v or 0-3.3v analog outputs)
* 2 pressure sensors (0-5v or 0-3.3v analog outputs)
* 2 current sensor (0-500mv outputs)

Except for the current sensors, the rest have response times, that mean the
output changes if you are lucky at 10Hz. See comments above about A/D.
I actually doubt that the current sensors (probably for measuring
power supply load to this board and main radio control) actually need to
be monitored more than 1Hz anyway.

I would also question the need for 16bits of resolution. I doubt any of
these sensors have more than 10 or at most 12 bits worth of signal.
Actually I wouldn't be surprised if 8 bits was overkill.

Albert, you need to ask what is the resolution you need for acceptable
results and also what resolution the sensors are capaple of.

Robert

.

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