RU2309381C1 - Device for determining coordinates of object - Google Patents

Abstract

FIELD: measuring technique.

SUBSTANCE: device comprises self-collimating optical system (2) that forms an image of cross-shaped light source (3) on matrix (4) of photodetectors. The position of the image is determined by rotation angle of mirror (1) connected with the object. Commutator (5) reads signal from matrix (4). Correlator (6) and amplitude comparator (7) determine the column number in which the signal varies, and using this number, counter (8) records the measured value in relative coordinates. The signal is supplied to the input of shift recorder (10) from the output of commutator (5) and to the first and second outputs of AND circuit (13) from the first and second outputs of the recorder directly and through AND-NOT circuit (11), respectively. The signal is fed to the third input of AND circuit (13) from the output of generator (12), and to the first inputs of first (15) and second (16) dividers from the output of the AND circuit. The signal is supplied to the second input of first divider (15) from the output of first counter (8), and to the second input of second divider (16) from the output of first divider (15). The signals supplied from the output of first divider (15) and second divider (16) are proportional to the values of velocity and acceleration of movement of the object.

EFFECT: enhanced precision.

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Description

The invention relates to measuring technique and can be used for measuring small linear, angular displacements, speeds and accelerations.

Closest to the invention is a device for determining the position coordinates of an object, comprising a mirror coupled to the object, an autocollimation optical system, a cross-shaped radiation source connected to the object, a rectangular array of photodetectors and a registration circuit connected to the rectangular array installed along the light beam, while the registration scheme is made in the form of series-connected commutator, correlator, amplitude comparator and first counter, control unit, trans the output of which is connected to the control input of the switch, and the second to the control input of the first counter, the output of which is the outputs of the angular coordinates of the positions of the object in two planes, the radiation source and the photodetector array are rotated so that the axis of symmetry of the photodetector matrix and the side of the radiation source form an acute angle moreover, the tangent of the angle formed by the axis of symmetry of the matrix and the side of the radiation source is a multiple of the ratio of the distance between rows or columns of the matrix to the length of the row or column TSA (USSR Author's Certificate No. 1483254, cl. G01B 21/00, 05/30/1989).

The disadvantage of this device is the inability to determine the angular velocities and accelerations of the object.

The purpose of the invention is the expansion of functionality by measuring angular coordinates, speed values and accelerating the movement of an object.

The essence of the invention lies in the fact that in the device for determining the coordinates of the position of the object, containing a mirror coupled to the object, an autocollimation optical system, a cross-shaped radiation source connected to the object, a rectangular array of photodetectors installed along the light beam and a recording circuit connected to the rectangular matrix where the registration circuit is made in the form of series-connected commutator, correlator, amplitude comparator and first counter, control unit, trans the output of which is connected to the control input of the switch, and the second to the control input of the first counter, the output of which is the outputs of the angular coordinates of the positions of the object in two planes, while the radiation source and the photodetector array are rotated so that the axis of symmetry of the photodetector matrix and the side of the radiation source form a sharp angle, and the tangent of the angle formed by the axis of symmetry of the matrix and the side of the radiation source, is a multiple of the ratio of the distance between the rows or columns of the matrix to the length of the row and and the column, an additional shift register, an NAND element, a pulse generator, an And element, a second counter, first and second dividers are introduced, the output of the comparator connected to the input of the shift register, the first and second outputs of which are connected directly to the first and through the And element, respectively -NOT with the second inputs of the element And, the output of the pulse generator is connected to the third input of the element And, the output of which through the counter is connected simultaneously with the first inputs of the first and second divider, the output of the first counter is connected to the second Odom first divider, whose output is connected to a second input of the second divider, the outputs of the first counter, the first and second dividers are respectively first, second and third outputs of the device for determining position coordinates of the object.

Salient features of the claimed device are the shift register, the AND element, the pulse generator, the AND element, the second counter, the first and second dividers, and new connections between the elements of the device circuit.

Figure 1 shows a block diagram of a device; figure 2 - shows the principle of operation of the autocollimation optical system; figure 3 - matrix of photodetectors and autocollimation image of a cross-shaped radiation source; figure 4 - matrix of photodetectors, on which the hatching shows the photodetectors, the output of which there is a signal; figure 5 - timing diagrams of signals at different points in the block diagram of the device.

The device comprises a mirror 1 connected to the object, an autocollimation optical system 2, a cross-shaped radiation source 3 and a rectangular matrix 4 of photodetectors placed in the focal plane of the autocollimation optical system 2, switch 5, correlator 6, amplitude comparator 7, counter 8 and control unit 9, the shift register 10, the element AND 11, the pulse generator 12, the element 13, the second counter 14, the first 15 and the second 16 divider, and the output of the comparator 5 is connected to the input of the shift register 10, the first and second output of which o connected to the first and second inputs of the element And 13, respectively, directly and through the element AND-NOT 11, the output of the pulse generator 12 is connected to the third input of the element And 13, the output of which through the counter 14 is connected simultaneously with the first inputs of the first 15 and second 16 dividers, the output the first 8 counter is connected to the second input of the first 15 divider, the output of which is connected to the second input of the second 16 divider, the outputs of the first 8 counter, the first 15 and second 16 dividers are respectively the first, second and third outputs of the device for determining Jelenia coordinate position of the object.

Consider the operation of the device on the example of determining the coordinates of the angular position of the object. In this case, the optical coupling of the matrix and the radiation source is carried out using an autocollimation optical system, the principle of which is illustrated in Fig.2.

Figure 2 shows a mirror 1 associated with an object whose angular position • to be measured. The ability to rotate at angles α and β is conventionally shown by placing mirror 1 in the axes of the suspension. Mirror 1 is in the field of view of the autocollimation optical system 2 (shown conditionally), in the focal plane of which there is a cross-shaped radiation source 3 and an array of 4 photodetectors.

The light flux of the source 3 passes through the autocollimation optical system 2 and enters the mirror 1. The light flux reflected from the mirror 1 again passes through the autocollimation optical system 2 and enters the photodetector array 4, on which the autocollimation image of the cross radiation source 3 is formed (conventionally shown by the cross) . When the mirror 1 is rotated by the angles α and β, the image of the source 3 will move along the matrix 4 in the horizontal and vertical directions, respectively.

Figure 3 shows an enlarged view of the matrix 4 of the photodetectors and autocollimation image of a cross-shaped radiation source.

Consider one of the lines of the cross, for example, vertical. The interaction of this line with a rectangular matrix when they are rotated through an angle φ is equivalent to the interaction of a line without a turn with v matrix made in the form of a transverse grid, i.e. when the line is moved, the signals in the photodetectors will appear sequentially in each row and by the number of the row in which the column number changes, and one can judge the rotation angle. The resolution will be determined by the ratio of the size "a" of the photodetector to the number of N rows.

For different values of the angle φ, a different resolution is obtained. The change in resolution occurs discretely at such values of the angle φ at which the line of the cross is parallel to the diagonal of one or more columns of the matrix.

It is advisable to choose the tangent of the rotation angle as a multiple of the ratio of the distance between the rows or columns of the matrix to the length of the row or column, i.e.

where K = 1, 2, 3 ... W (M);

a is the distance between the rows (columns);

b is the length of the row (column);

N {M) - the number of rows (columns).

When K = 1, the maximum resolution is achieved, equal to (in the case of angular measurements)

where f is the focal length of the lens.

Similarly, you can determine the angular position of the object in a different coordinate.

The switch 5 reads the signals from the photodetectors of the matrix in two stages sequentially in rows and columns. The correlator 6 compares the sequence of row or column signals with the reference signal S (t). The amplitude comparator 7 compares the signal from the correlator 6 with a threshold level of U then. The pulse counter 8 counts the pulses of the control unit 9 from the moment the signals from the photodetectors are read in rows or columns until it is stopped by the signal from the amplitude comparator 7 and thereby registers (in relative units) the value of the angular displacement.

The operation of the registration scheme is illustrated by the timing diagrams depicted in figure 5.

To determine the coordinate α, the switch 5 reads the signals from the photodetectors of the matrix 4 in columns, starting from the first in the direction of the arrow in figure 4 (from top to bottom).

In the correlator 6, the bitwise multiplication of the signal S _a with the signal S (t) and the summation of the multiplication results, and the signal S _{ka is formed} .

At time t _{a, the} signal S _ka reaches a maximum, while the time from the start of reading to time t _{a is} proportional to the coordinate α. Since the read pulses from the control unit 9 go at regular intervals, the coordinate α is proportional to the number of read pulses generated at time t _a .

The moment t _{a is} determined using the amplitude comparator 7, which generates a signal when the signal S _ka reaches a maximum. Since the pulse counter starts at the moment of reading and stops with a signal from comparator 7, the readings N _{a of the} pulse counter 8 are proportional to the coordinate α.

The signal from the output of the switch 5 also goes to the input of the shift register 10, from the first and second output of which goes to the first and second input of the And 13 element, respectively, directly and through the And-HE 11 element, the signal from the output of the pulse generator 12 comes to the third input, from the output of element And 13, the signal enters through the second counter 14 to the first inputs of the first 15 and second 16 dividers, the second input of the first 15 divider receives a signal from the output of the first 8 counter, from the output of the first 15 divider the signal goes to the second input of the second 16 divider . The signals coming from the output of the first 15 and second 16 divider are proportional to the value of the speed and acceleration of the movement of the object.

Similarly, the coordinate β is determined, while reading occurs along the rows of the matrix, starting from the first in the direction of the arrow shown in figure 4 (from left to right).

The source of information.

1. USSR author's certificate No. 1483254, cl. G01B 21/00, 05/30/1989 (prototype).

Claims (1)

A device for determining the coordinates of the position of the object, containing a mirror connected to the object, an autocollimation optical system, a cross-shaped radiation source connected to the object, a rectangular array of photodetectors installed along the light beam and a registration circuit connected to the rectangular matrix, the registration circuit is made in the form of series-connected a switch, a correlator, an amplitude comparator and a first counter, a control unit, the first input of which is connected to the control input to switch, and the second with the control input of the first counter, the output of which is the outputs of the angular coordinates of the position of the object in two planes, while the radiation source and the photodetector array are rotated so that the axis of symmetry of the photodetector matrix and the side of the radiation source form an acute angle, and the tangent of the angle formed the axis of symmetry of the matrix and the side of the radiation source, a multiple of the ratio of the distance between the rows or columns of the matrix to the length of the row or column, characterized in that shear the first register, the AND element, the pulse generator, the AND element, the second counter, the first and second dividers, the output of the comparator connected to the input of the shift register, the first and second outputs of which are connected to the first and second inputs of the AND element, respectively, directly and through the AND element -NOT, the output of the pulse generator is connected to the third input of the element And, the output of which through the counter is connected simultaneously with the first inputs of the first and second divider, the output of the first counter is connected to the second input of the first divider, the output of which is connected nen with a second input of the second divider, the outputs of the first counter, the first and second dividers are respectively the first, second, third output device to determine position coordinates of the object.

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