Theory Of Operation - Geosense IPI-V-1 Instruction Manual

V1.0 September 2017

1.2 Theory of Operation

inclinometer casing is a specially machined plastic tube that is installed in, or
fixed to, a structure. The tube has 4 equally spaced, parallel 'keyways' in its
inner surface, into which wheeled probes can be inserted, thereby maintaining
their orientation. The inclinometer casing is designed to move with the
structure into which, or onto which, it is fixed, if the structure changes shape.
In order to detect any changes in the horizontal direction (vertical or inclined
access tubes) or vertical direction (horizontal access tubes), an inclinometer
systems is inserted into the inclinometer casing.
An inclinometer system comprises a wheeled probe that runs in the
inclinometer casing keyways and includes very sensitive electronic tiltmeter(s),
a connecting cable and a readout.
Portable inclinometer systems are commonly used where monitoring is to be in
-frequent or manual monitoring is in-expensive. These systems are used to
determine the inclination of an inclinometer casing at 0.5m intervals along it
length. This information is processed to generate a profile of the inclinometer
casing, with respect to vertical and sequential profiles being compared with
each other to detect changes.
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Geosense In-Place Inclinometers (IPI's) are intended to remain 'in-place'
within the inclinometer casing and are employed where continuous or frequent
monitoring is required. The completed installation is, in effect, a string of
interconnected, inclinometer probes, separated by rods or wires and
suspended in the inclinometer casing.
Each Geosense
Mechanical System (MEMS) tiltmeter. The device is extremely sensitive and is
detects changes in the angle of the module, if the surrounding inclinometer
casing moves. Installations close to vertical can measure movements in 2
directions, whereas
Since they are digital, the cable from the IPI modules can be connected
together in a 'string', thereby minimising the cables from each installation.
In most cases, Geosense
'Universal joints' so as to maintain a physically connected profile of
measurement. This is critical if a 'truly accurate' profile of the inclinometer
casing is to be measured. (Where steel rope is used to interconnect the IPI
modules, a true profile cannot be measured).
In addition, it is vital that the IPI modules are suspended between the walls of
the inclinometer casing and do not touch them at any time during the
monitoring period.
Once installed and suspended in the inclinometer casing, the IPI sensors can
be interrogated by various means. The readings from each module will be the
angle of the sensors, with respect to vertical, in either degrees or 'sine of the
angle' units and the temperature of the module.
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IPI sensor module includes a very sensitive Micro Electro-
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IPI's are mechanically inter-connected using
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