Compensation Signals - Cont'd -141200145

A dial is attached to the shaft of the linear synchro (B7),

generator section, furnishing the damping signal

indicating the north-south component of own ship's speed.

voltage, and at the same time the control transformer

rotor of the resolver (B4) is positioned relative to the

The latitude computer, which produces the

ship's heading. The resolver (B4) functions to resolve

horizontal and vertical earth rate compensation signals,

own ship's speed and course inputs into S cos C or

consists of a type 1 computer amplifier, a motor-

north-south speed and S sin C or east-west speed. These

tachometer (B9), a resolver (B10), and an earth rate

are the speed compensation signals needed. A dial is

reference transformer (T1).

coupled to the shaft of the resolver (B4), indicating own

ship's course.

The tangent latitude computer, which produces the

meridian gyro east- west compensation signal, consists

The north-south acceleration computer (fig. 4-28)

of a type 2 computer amplifier and a resolver (B11). A

contains a north-south speed repeater consisting of a

dial attached to the shaft of the resolver (B11 ) indicates

linear synchro and dial (B7) and a motor-tachometer

the ship's latitude.

(B8). The computer also includes a limiting or nonlinear

network, a north-south acceleration signal amplifier,

The input to the latitude computer is the north-south

and a type 1 computer amplifier.

speed plus drift signal, and the inputs to the tangent

latitude computer are the east-west speed signal, and the

The north-south speed signal voltage is fed to the

initial, manual, ship's latitude setting. The latitude is set

stator of the linear synchro (B7) in series opposition with

by the compass operator at the start of a voyage, and

the stator voltage induced by the synchro rotor, The

thereafter the latitude computer keeps the latitude up to

difference between these two voltages is applied in

date, automatically, wherever the ship may go.

series with the north-south acceleration signal amplifier

output to the input of the type 1 computer amplifier. The

The north-south speed plus drift signal is fed, in

output of the type 1 computer amplifier drives the motor

series opposing, with the output of the generator section

section of the motor-tachometer (B8) at a speed

of the motor tachometer (B9), which produces a

proportional to the rate of change of the ship's

damping voltage for stabilization of the servoloop, to

north-south speed, and positions the rotor of the linear

the input of the type 1 computer amplifier. The type 1

synchro (B7) until the stator voltage due to rotor position

computer amplifier output drives the motor section of

equals the north-south speed signal voltage. A voltage

the motor-tachometer (B9) at a speed corresponding to

proportional to the rate of change of the ship's

north-south speed plus drift. The motor shaft is geared

north-south speed is obtained from the generator section

down (240 million to 1) to position the rotor of the

of motor tachometer (B8) and applied through a limiting

resolver (B10) so that it follows the changing ship's

network to the input of the north-south acceleration

latitude. At any time, the position of the rotor of the

signal amplifier, whose output is the north-south

resolver (B10) corresponds to the latitude position of the

acceleration compensation signal to the meridian gyro

ship. With a reference voltage, representing earth rate,

gravity reference system, When the elcctrolytic bubble

from the transformer (T1) impressed on the rotor of the

is displaced due to accelerations, it starts to return

resolver (B10), and the rotor set at the ship's latitude,

rapidly at first to its neutral position, then slows down.

the resolver (B10) functions to resolve its earth rate

This is due to the viscosity of the electrolyte and the

referencc voltage and latitude inputs into an output

design of the level. By connecting the acceleration

proportional to earth rate times the cosine of the latitude,

signal in series with the linear synchro before applying

or horizontal earth rate and earth rate times the sine of

the voltage to the motor, of the motor-tachometer, the

the local latitude or vertical earth rate.

motor speed is made to vary nonlinearly. This nonlinear

The amplified east-west speed signal from the type

speed is designed to be proportional to the output of the

electrolytic bubble level. In addition, the output signal

2 computer amplifier is fed to the rotor of the resolver

voltage from the electrolytic bubble level is proportional

(B11). With this voltage proportional to east-west speed

to the displacement of the bubble over a limited range,

on its rotor, and the rotor positioned to the ship's latitude,

beyond which it saturates. If the accelerations are of

the outputs of the two resolver stator windings are

sufficient magnitude, the electrolytic bubble level will

proportional to cast-west speed times the sine and cosine

saturate. This factor is also compensated for by applying

of the ship's latitude. The output of the cosine stator

the output of the tachometer generator to a limiting

winding representing the cosine of east-west speed and

network of rectifiers. The output of this network is

latitude, however, is fed back, inversely, to the input of

amplified and used as the tachometer feedback voltage

the type 2 computer amplifier so that the resultant output

to the input of the type 1 computer amplifier.

of the amplifier represents the product of east-west

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