SU647611A1 - Method of determining accelerometer follow-up system statism - Google Patents

Description

element and basic approach to the vector of acceleration of gravity. The axis 1 of the reference of the sensitive element 2 is perpendicular to the axis X and. U accelerometer and. lies in a horizontal position. The measuring axis 3 is perceptual to the plane passing through the axis of suspension and the center 4 of the inertia of the sensing element. The base plane 5 with the vector of 6 accelerated gravity forms the angle C1 (see drawing, pos. A), the angle (ISO tj)) is in the position; shown in the drawing pos. b, angle (18О + () - at the positions shown on the drawing of position c, angle minus f - at the position shown on the drawing of positions pos. Г

The output signals of the accelerometer in price, feedback are described by the following expressions: in the position shown in the drawing (pos. A), the output signal XT of the accelerometer W

veins

is .jial-Ktoio- g 5Ш ()

Hi

(v) (oC2, -if) .21

 .g

(y, u

-t-P,

3 th-in .2

where K is the steepness of the static calibration characteristic of the accelerometer;

GQ is the accelerometer signal component, independent of acceleration;

o6v base error (non-perpendicularity of the measuring axis to the base plane along axis 2 ();

tp is the static displacement of the sensitive element caused by the presence of acceleration along the measuring axis; RL, R, - coefficients of quadratic and cubic nonlinearity, respectively

In the position shown in the drawing pos. b, the output signal of the accelerometer Aven

iso-C)) I Y og; n (V-d.2i)

".P. ,, F). (21

3g, T &

in the position shown in the drawing pos. in, the output signal and .Q Q,., is equal to

 iSOOT ui ° o - g Sirj (1 - OC 2 -CH) -i; P2.sin2 (lytOi2i-bCp) -.

. () (S)

In the box {shi, shown in the drawing pos. g output equal to

m toil to о - g S i Ц- 0 and -) +

(C-oSa-f) -Rzё 5 1 -La-f). W Statism of the following accelerometer system is

.

H-Y -. (5)

)

Determining from the expressions (1) and (4) the angle с taking into account its smallness and taking co9оЬ2: .1, after substitution in expression (5), we obtain for statism

Vi900-v c,). LI. (O, b-U (a) - U,

, - b

4k b1pts) SOB

The accuracy of the determination of statism depends on the angle tjl

If a relative error is permissible

in the definition of statism

equals

AW

but

Oy-y

where D11 is the absolute value of the error of determination of J, then the angle φ ba-. the core plane with the vector of acceleration of gravity should be set within

Gy gk-

45 -psBSHl- iWiAS + arcsmn -ii- (3)

N 242

Static determination is made from the large constant output signals of the accelerometer in the feedback circuit and the output of the accelerometer does not pass a zero non-phase signal from the displacement sensor and the interference signal, which are eliminated by the phase demodulator of the accelerator servo system amplifier.

Claims (1)

Invention Formula The method of determining the statistics of the tracking system of a feedback accelerometer by measuring the displacement of the sensitive element from the acceleration along the measuring axis is about the same, so that, in order to increase accuracy, the accelerometer is successively deployed relative to of the vector of acceleration of the force of tinplate to the west. 180 + f, 18 y the total angles + C) and –1) measure the constant output signals in the feedback circuit, the tracking system’s statism is determined from the measured signals and given angles, and the angle is chosen according to the inequality . (bGfir 45 ° -arcsin-J i6 {, t445 ° 4 oifCsinn 1, 2h 2 where & is the relative error of the definition of statism, and the axis Accelerometer suspension horizontally. Sources of information taken into account in the examination 1, Ageikin DI, and others. Sensors of control and adjust, M., 1965, 485-551. 2, ttniepnational Aerospace Dn & tvumentation Sympos umoi the CrauilS-d nnetHuie of Tech notogy, Crau {ied, Be (iioicl, EngBdnd, March 197O. m tf