Watson Industries, Inc.
DMS-EGP02 Rev A 03/28/2008
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Appendix B
Sensor Test Instructions
Tests within this section have been designed to allow the user to verify the correct operation of the
sensor without the use of elaborate test equipment other than a means of accurately observing the
outputs. The “Hyperterminal” program provides a suitable means of observing the outputs.
B.1 Parameter Exercise Test
After successful initialization, move the sensor in all three axes using both linear and angular
motion, making certain each of the measurement parameters responds to the motion.
B.2 Angular Displacement Scale Factor Tests
After successful initialization, place the sensor on a level surface and observe the pitch and roll
displacement signals. Place the sensor on a pivot and incline the sensor by a small angle of 6 to 10
degrees in the pitch. A suitable pivot is a 10mm square bar attached to the sensor base plate with
adhesive tape. Give the "Reference" command. The signals from the simulated pendulums will be
output instead of the normal angular displacement signals. Careful note should be taken of the
angles indicated in the reference mode. The sensor should then be tipped on the pivot into the
other stable position and the angle again noted.
The procedure of tipping the sensor should be repeated in “Inertial Mode”. The angles obtained
should agree with those noted in “Reference Mode”.
Repeat this procedure for the Roll axis. The same pivot may be used, but some care will be needed
to avoid exceeding the 100 °/second limit. A more appropriate size of bar would be 5mm square.
B.3 Accelerometer Scale Test
After successful initialization, place the sensor on a level surface and monitor the acceleration
outputs. Observe that the X and Y outputs read near zero while the Z axis will read -1G within the
accuracy of the sensor.
Set the sensor at a 45° angle to the horizontal in Pitch only. The value of X and Z acceleration
should read 0.71G, within the accuracy of the sensor, while the Y acceleration should remain at the
level value. The values of Forward, Lateral and Vertical Acceleration should remain at the values
when level.
Repeat the test for the roll axis of the sensor. Under this test, Y and Z acceleration will read 0.71G
and the X acceleration will retain its value at level.
