Inertial
Sensor Technology
How Servo
Inclinometers work
Servo inclinometers are extremely sensitive transducers measuring
horizontal and vertical inclination with virtually infinite resolution
using a 'taut band' detection mechanism.
Features
Ranges ±1° to ±90°
1500g mechanical shock
DC input - DC output
Output proportional to sine of
tilt angle
Resolution down to 0.1 arc second
Typical applications include road grading, borehole alignment,
satellite dish alignment, tilt train control and other applications
where high accuracy of tilt measurement is required.
All units are manufactured under ISO 9001 conditions.
All inclinometers operate as a closed loop torque balance servo
system (see figure below).
The heart of this gravity referenced angle detector is a torsional
flexure supported moving mass system that is rugged enough to
withstand severe shock and vibrations and still maintain excellent
precision and accuracy. The servo system electronics, torque
motor and feed?back sensor are all enclosed within an environmentally
sealed housing permitting operation under hostile conditions
without degrading performance.
As the inclinometer
is tilted through some angle (ø) along its sensitive axis,
mass 'A' tries to move in the direction of tilt as a result of
a force (torque) applied to the mass by the normal component
of gravitation acceleration.
The resulting change in position of mass 'A' is detected by position
sensor 'B', which produces an error signal output. This DC error
signal is fed to a servo amplifier whose output is a DC current
coupled to the armature of torque motor 'C' through 'Ro'. Current
applied to the torque motor armature produces a torque that opposes
the gravitational force acting on mass 'A' and moves it back
towards its original position.
The current passing through 'Ro' generates a voltage across 'Ro'
that is proportional to the normal component of the gravity vector.
The normal component is the product of the essentially constant
gravity vector times the sine of angle ø. Therefore, the
output voltage across 'Ro' is proportional to the sine of the
tilt angle ø.
