Preparing to Collect Data
By Mina Cappuccio
July 21, 1999
As the head researcher on the project, I choose the
measurements that that will be taken during the test. So six weeks ago
I submitted to the Test Manager, Jules Gustie, the data requirements and
he has assigned the mechanics and engineers to accomplish this work.
The model is just about to come out of the prep room.
While it was in the prep room the balance was installed on the model and
checkloaded. The model was assembled and the model was plumbed to the
Electronic Scanned Pressures (ESP).
During this test, we will be measuring the air pressure
on the surface of the model at over 300 locations on the wings. On one
side of the plane the pressures are being measured on the top of the wing
and on the other side of the plane we are measuring the pressures underneath
the wing. At each of the locations where pressure is measured there is
a pinprick-sized hole which is attached to a tiny stainless steel tube
which is attached to the ESP modules. There are five five modules, each
with 64 transducers, in the model. The ESP system takes the air pressure
measurement as a voltage. The voltage is sent to the data acquisition
system and converted to an air pressure measurement.
Some of the data I have asked for is visual data,
both video and digital still images. To collect this data we have painted
the model. We do this before putting the model in the tunnel so we don't
spill any paint in the tunnel.
The data acquisition system has
been customized for this test. This means that the constants for this
particular model have been put into the computer program. . Calibration
constants for converting analog and digital signals have also been put
in the program. These signals come from instruments like the balance,
ESP modules, and motors that drive parts remotely like the canard.
| Here is the empty tunnel with the crane ready to mount
the model |
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Today, the model will be moved from the model prep
room to the tunnel. This week will be spent making sure all the instruments
are connected to the data acquisition system and are working properly.
The model will also be put in its final configuration for when we are
ready to run.
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