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jlane84
09-16-2004, 09:01 PM
Hi,

I am a PhD student looking at knee joint stiffness following total knee
arthroplasty and am wondering if anyone out there with experience in LabView
programming can help?

I trying to simultaneously acquire continuous data from a torque transducer
and a Biometrics electrogoniometer using LabView Express 7.0. Torque data is
collected directly through the USB port, the electrogoniometer data is being
acquired through a Data Translation DAQ module connected to the other USB
port.

I have written a LabView program which will acquire the data from both
channels using DT-LV Link VI's for the electrogoniometer data and
manufacturer supplied VI's for the torque data. I have successfully included
all these sub-VI's in a single loop and can write the data to a file but
cannot work out how to get the program to acquire the data absolutely
synchronously.

I can set the data acquisition rate for the electrogoniometer but the torque
data VI's are written to sample as quickly as the processing power will
allow. I need the torque displacement data to be synchronous but this is not
happening. I am not sure if the problem is just in writing to the file or in
the actual acquisition. I am wondering if I need to write the data to a
buffer before writing to file? My programming skills are limited and we have
no-one in our University who knows how to use LabView.

Has anyone got any ideas or has similar VI's which they might be prepared to
share?

Your hopefully,

Judith Lane
School of Health Sciences
Queen Margaret University College
Edinburgh
Scotland

Email:jlane@qmuc.ac.uk

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