User's Manual

MicroStrain, Inc.
Sample Duration Calculations
Datalogging, streaming, low duty cycle and high speed streaming sampling sessions can
all be set to last a finite duration, a finite amount of time. Finite sample duration is a
value ranging from 100 to 65500, in increments of 100.
A datalogging example: We set the number of active channels to 3. We set the sample
rate to 32. We set the sampling duration to 1000. We trigger the session. We download
the session. We find that we have 1000 rows of data, with each row containing 3 channels
of sensor data. We see that the session lasted ~31.25 seconds.
Another datalogging example: We set the number of active channels to 1. We set the
sample rate to 1024. We set the sampling duration to 10000. We trigger the session. We
download the session. We find that we have 10000 rows of data, with each row
containing 1 channel of sensor data. We see that the session lasted ~9.77 seconds.
From this is becomes clear how the sampling duration can be thought of as a time setting:
• In our first example, we can divide a sampling duration of 1000 by a sample rate
of 32 to equal ~31.25 seconds.
• In our second example, we can divide a sampling duration of 10000 by a sample
rate of 1024 to equal ~9.77 seconds.
A streaming example: We set the number of active channels to 3. We can’t set the
sample rate because that is fixed in hardware and we know it will be 617. We set the
sampling duration to 10000. We start the session. We save the session. We find that we
have 10000 rows of data, with each row containing 3 channels of sensor data. We see that
the session lasted ~16.21 seconds. As before, 10000 sampling duration divided by 617
sample rate = ~16.21 seconds.
A low duty cycle example: We set the number of active channels to 3. We set the sample
rate to 1. We set the sampling duration to 100 (100 is the minimum setting in Agile-
Link™ software). We start the session. We save the session. We find that we have 100
rows of data, with each row containing 3 channels of sensor data. We see that the session
lasted ~100 seconds. As before, 100 sampling duration divided by 1 sample rate = ~100
seconds.
A high speed streaming example: We set the number of active channels to 4. We can’t
set the sample rate because that is fixed in hardware and we know it will be 1000. We set
the sampling duration to 10000. We start the session. We save the session. We find that
we have 10000 rows of data, with each row containing 4 channels of sensor data. We see
that the session lasted ~10 seconds. As before, 10000 sampling duration divided by 1000
sample rate = ~10 seconds.
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