SU996863A1 - Laser goniometer - Google Patents

Description

The invention relates to a measuring apparatus and can be used to dynamically measure the angles of various objects, for example, multiple magnetic prisms.

 A goniometer containing a rotary platform / is known: with a drive, an angular displacement sensor, mechanically connected to the rotary platform, a block (forming intervals of axes, the input of which is connected to the angular limiter sensor, and the output connected to an L13 drive. The goniometer's fault is low accuracy of measurements.

The most competitive to the invention according to its technical nature is a laser goniometer, containing a rotary (1) attenuation) MI with a drive, KOL. target laser mechanically coupled to the turntable; time interval interlock unit, oscillator, frequency divider, frequency discriminator, Information processing unit, the first input of which is connected to the time interval shaping unit, output, of a ring laser, is connected to the Secondary input of the information processing unit and the second input of the frequency detector, the second one.

the input of which is connected to the output of the frequency divider, whose input is connected to, connected to the generator, the output of the frequency discriminator is connected to the control input of the C2 drive.

The disadvantage of the laser goniometer is the dependence of the measurement results on the change in the absolute speed of rotation of the rotary plate 10 of the form with a {ring laser.

The purpose of the invention is to improve the measurement accuracy).

This goal is achieved by the fact that the laser goniometer is equipped with a second frequency divider, a second frequency 1m discriminator on the angular displacement sensor, is mechanically connected to the turntable, the ring laser is controlled by

20, the output of the angular displacement sensor is connected to the first input of the second frequency discriminator, the second input of which is connected to the output of the second frequency divider, the input of which is connected to the generator, the output of the second frequency discriminator is connected to the control input of the ring laser.

The drawing shows a functional diagram of a laser goniometer.

The goniometer contains a rotary platform 1 with a drive, an angular displacement sensor 2, a ring laser 3, a time interval formation unit 4, a generator 5, a frequency divider 6, a frequency discriminator 7, a second frequency divider 8, a second frequency discriminator 9, an information processing unit 10.

Laser grniometer works as follows.

The rotary platform 1 with the drive causes the rotation of the sensor 2 of the angular displacements and the ring laser 3. When the rotary platform 1 rotates, the block 4 of formation of time intervals forms time intervals whose duration is proportional to, for example, the angles between the individual faces of the polyhedral prism.

The time interval formed by the time interval forming unit 4 is filled with pulses removed from the code of the ring laser 3, in the processing unit 10 of the information ""

To stabilize the frequency of the pulses taken from the output of the ring laser 3, two frequency self-tuning loops are used.

The first branch consists of a generator 5, a frequency divider 6, a frequency discriminator 7, the output of which is connected to the drive of the turntable 1.

The second branch consists of an angular displacement sensor 2, a generator 5, a second frequency divider 8, a second discriminator 9, the output of which is connected to a control input of a ring laser 3.

The pulses from the output of the ring laser 3 are fed to the first input of the frequency discriminator 7, the second input of which receives the pulses from the output of the frequency divider 6.

In the case of the difference between the frequencies generated by the ring laser 3 and the frequency divider 6., a signal is generated at the output of the frequency discriminator 7, changing the rotation speed of the turntable 1.

The pulses from the output of the sensor 2 angular displacements arrive at the first input of the second frequency discriminator 9, to the second input of which impulses come from the output of the second frequency divider 8.

In the case of the frequency difference between the angular displacement sensor 2 and the second frequency divider 8, the output of the second frequency discriminator 9 generates a signal that changes the frequency of the ring laser 3, for example, by moving one of the elements that change the optical path length of the beams.

Due to the presence of two branches of the automatic frequency control, the condition

  Kdu - to s7

l,

 -

cl

AZ

where is the angular frequency of the ring laser;

Cd, y - transfer coefficient of the sensor of angular displacements}

K, Kd - transfer coefficients of the first and second frequency dividers;

QQ is the angular velocity of the turntable relative to the base;

Kj. - goniometer transmission coefficient.

From the above dependence it follows that the angular frequency of the ring laser 3 does not depend on the absolute angular velocity of the ring laser, which makes it possible to increase the measurement accuracy.

Claims (2)

1. Patent QdA No. 3626512, cl. 6 01 B 11/26, 1971. 2. Authors certificate of the USSR 717956, cl. G 01 B 19/00, 1979 (prototype).