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PART NO: 860029-001
Last Revised 01/06/15
7.0 FIXTURING
The user provides fixturing for the KD-5100 electronics and sensors. The following information
establishes fixturing requirements for optimum system performance. The quality of the
measurement is both a function of Kaman’s system and your Fixturing.
Both the sensor and target fixturing must be structurally sound and repeatable.
7.1 Factors that degrade performance:
Unequal Loading
: This refers to an unequal amount of conductive material within the field of
one sensor of a pair as opposed to another (the sensor’s field is approximately three times its
diameter). Unequal loading causes asymmetrical output from the sensor, which induces non-
linearity in the system output. Ideally, no conductive material other than the target should be in
the sensor’s field. Some loading may be acceptable if it is equal and the sensors are calibrated
in place. Even then, sensor loading may cause non-linearity. If unable to calibrate – loading is
too great.
Unequal Displacement
: For targets using a pivot point mount (examples, Figures 3 & 4) the
system should “see” equal displacement: i.e., the pivot point of the target is perfectly centered
between the sensors. If the pivot point is a fraction of a mil off it can introduce non-linearity into
the system.
7.2 Pivot point requirements:
The pivot point must be a common line between the centerline of a pair of sensors.
The axis of tilt must be a perpendicular bisector of a line between the centerlines of a sensor
pair.
The pivot point must be positioned on the target so as not to introduce a translation error. This
error, a function of angle, is caused by slight changes in the effective null gap as the target
moves about the pivot. This results in non-linearity.
The pivot point must not change or move with time.
