MEMS Digital Inclinometer System with Android
Instruction Manual
ICM0099A
23
Step 3 - Select the desired graphs
Once the desired data set has been selected, the Digital Inclinometer app may plot 5
different types of comparison graphs for either Axis A or Axis B. The 5 comparison graphs
are:
•
Checksum
•
Mean Deviation
•
Absolute Position
•
Incremental Displacement
•
Cumulative Displacement
Checksum
Checksum in A+/A- plane = A+ plus A-
Checksum in B+/B- plane = B+ plus B-
Checksum should be reasonably constant and of small magnitude; large and inconsistent
Checksums may indicate that a problem exists. However, the consistency of checksums
from survey to survey is more important than the actual value of the checksums. Checksum
data should be monitored during the survey as a check on data integrity. Note that high
checksums can be expected if a settlement coupling has been encountered, a checksum of
the order of (+0.0045m and -0.0035m) or (+0.0147ft and
–0.0114ft) would be reasonable at
consecutive depths/couplings.
Mean Deviation
A+/A- mean deviation in the A+/A- plane = (A+ minus A-)/2
B+/B- mean deviation in the B+/B- plane = (B+ minus B-)/2
This represents the mean deviation at each depth.
Absolute Position
An absolute position value at a particular depth is the summation of mean deviations,
starting from the bottom up to that particular depth. The Absolute Position is the profile of the
access tube with respect to the vertical axis in a given plane. The Absolute Position can also
be calculated from the top down, if required,
using Inclinalysis™ software.
Incremental Displacement
The Incremental Displacement is the difference in values of mean deviation between the
base file (i.e., the first set of readings taken) and a selected file(s) (usually the latest set of
readings) at e
ach depth. This plot can be generated using Inclinalysis™ software.
Cumulative Displacement
The Cumulative Displacement value at a particular depth is the summation of incremental
displacements starting from the bottom up to that particular depth.
The profile represents the actual movement (or displacement) which has occurred at all
depths between the times that the two sets of readings were obtained.
4.3.9 A
DD
R
EADINGS
The Digital Inclinometer app’s primary function is to take readings at the borehole. The “Take
Reading
” feature commences when the user selects the Add Reading function from the View
Borehole Readings screen.
