User's Manual

IDS Ingegneria Dei Sistemi S.p.A. N doc: MN/2009/071 - Rev. 1.1

IBIS-S v. 1.0 - User Manual

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6. USEFUL TIPS

6.1 Installation

The successful performance of a field measurement campai

gn starts with the initial

inspection survey. The scope of this survey is the evaluation of the following aspects:

• Identification of a suitable installation point for the IBIS-S in terms of scenario

visibility and stability of the point the equipment will sit on. The characteristics

of a good position can be summarised as:

o direction of the displacement to be measured coincides with the ideal line

traced between the sensor and the measurement point;

o there being sufficient space to operate safely and to position the tripod, the

IBIS-S case and for the operators to move around;

o easily accessible to permit all the required material to be brought to the site.

• An evaluation beforehand of the quantity, quality and position of reflecting

points present in the scenario;

• The possibility to install artificial reflectors if those present in the scenario are

not sufficient. Installation of artificial reflectors eliminates one of the advantages

of IBIS-S, because it means that there must be access to the site. However, the

use of artificial reflectors allows a better accuracy in displacement measurement

and identification of the point the displacement is measured for.

• The presence of possible disturbances due to vegetation, foliage or other

sources, near to the intended displacement measurement points.

• The number of measurement points and their location in the scenario.

The IBIS-S sensor measures displacements along the ideal line joining the sensor to the

point being examined (radial displacement), therefore if the real displacement occurs in

another direction, the detected displacement must be projected on the basis of geometrical

considerations (Fig. 6.1).

Fig. 6.1 – Projection of displacement data

Real displacement

Measured displacement