RU2282874C2 - Method for measurement of mismatching in two-dimensional servo systems and device for its realization - Google Patents

Abstract

FIELD: systems for determination of the direction or deviation from the preset direction, using the optical radiation.

SUBSTANCE: the device realizing the method has a video amplifier, threshold device, standard pulse generator, delay line, control unit, recording unit, standard image storage unit, four multipliers, four low-frequency filters, two subtracters, two amplifiers with an automatic gain control, in addition use is made of the fifth multiplier, the first and second function generators.

EFFECT: metering of the mismatching measurement error caused by interdependence of the channels, enhanced accuracy of determination of the mismatching and thus enhanced efficiency of automatic target tracking.

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Description

The invention relates to the field of two-dimensional television tracking systems, namely to television sighting systems.

и

эталонных изображений В(x-ΔХ) и В(x+ΔХ), сдвинутых на фиксированные значения ±ΔX, и текущего изображения В(x-Х), по которым определяют значение рассогласования Х как обратную функцию пеленгационной характеристики ΔК(Х)=К₁(Х)-К₂(Х) в каждом канале [1].A known method for measuring the mismatch in two-dimensional tracking systems, based on the differential (difference) method for constructing direction-finding characteristics of two channels, in which two values of the correlation function are calculated

and

reference images B (x-ΔX) and B (x + ΔX) shifted by fixed values ± ΔX, and the current image B (x-X), which determine the value of the mismatch X as the inverse function of the direction-finding characteristic ΔK (X) = K ₁ (X) -K ₂ (X) in each channel [1].

A device for measuring the mismatch with two independent identical channels for calculating the mismatch U _Δy and U _Δz , consisting of a video amplifier, a threshold device, a standard pulse generator, a delay line, a recording unit, a memory block of the reference image, four multipliers that multiply the current image with the reference shifted by ± τ per line and ± T per frame, four filters, two subtractors and two amplifiers with automatic gain control [2].

If there is a mismatch in only one (for example, Y) channel (Fig. 2), the correlation functions K _1Y (τ) = ΣB _tech (z, y) · B _op (z, yT), K _2Y (τ) = ΣB _tech (z, y) · B _op (z, y + T) of the current image B _tech (z, y) and reference (reference) images B _op (z, yT) and B _op (z, y + T) shifted by ± T over the frame (channel Y), the differential correlation function K _{diff Y} (τ) = K _2Y (τ) -K _1Y (τ), and hence the mismatch y _ISM (or z _ISM during the operation of channel Z) are calculated without errors.

A disadvantage of the known method and device is an error in determining the amount of mismatch during the joint operation of two channels, arising from the adoption of the hypothesis of independence of the channels for determining the mismatch. Actually there is a relationship of channels. So, if there is a mismatch in two channels (y ≠ 0 and z ≠ 0), the measured correlation function K _2Y (τ) will be less than its true value K _2Y (τ) _ist by the error δ _Y (Fig. 3). Similarly, in the channel Z: K _2Z (τ) = K _2Z (τ) _{ist −} δ _Z. It is characteristic that the errors in channels Y and Z are equal, since δ _Y = δ _Y = δ. Numerically, the error in measuring the values of correlation functions is determined by the absolute value of the product of real (true) discrepancies in two channels δ = | y · z |.

An object of the invention is to take into account the error of measurement of the mismatch caused by the interdependence of the channels, which will more accurately determine the mismatch and, thereby, increase the efficiency of automatic tracking of the target.

The solution to the technical problem by the method is that in the method for measuring the mismatch in two-dimensional tracking systems, based on the construction of a differential correlation function, when the reference images of the tracking object shifted by fixed values of ± T and ± τ are multiplied by the current channel image, and the result is integrated, thereby forming the correlation functions and subtracting form the differential correlation functions for both channels, which are signals, the proportions the ionic measured mismatch y _ISM and z _ISM for two channels, respectively, additionally calculate the estimated error value of the measured mismatch y _ISM and z _ISM for two channels as the product modulus δ ^* = | y _ISM · z _ISM | and increase the signal modules of the measured mismatch values in each channel | y _meas | and | z _rev | by the estimated error value δ ^* .

It is proposed to determine the error estimate of the mismatch as the modulus of the product of the measured mismatch values over two channels δ ^* = | y _meas · z _meas | Naturally, the measured values of the mismatch in the joint operation of the two channels will always be less than the true values: y _ISM <y and z _ISM <z. However, their consideration will significantly reduce the error in determining the mismatch in the joint work of two channels.

The inventive method is implemented in a device for automatically tracking a tracking object containing a video amplifier, the input of which is the input of the device, a threshold device, the input of which is the output of the video amplifier, a standard pulse generator, the input of which is the output of a threshold device, a delay line, the input of which is the output of a standard pulse generator , a control unit, to the input of which synchronizing pulses arrive, a recording unit, whose inputs are the output of the control unit, p whose teams overwrite the reference image, and the first output of the delay line, the memory block of the reference image, configured to generate image standards shifted by fixed values ± T and ± τ on channels Y and Z, respectively, where T is the image shift parameter on channel Y, and τ is the parameter of the image shift along the channel Z, the input of which is the output of the recording unit, the first, second, third and fourth multipliers, the first inputs of which are the corresponding outputs of the memory block of the reference image and second inputs - the second output of the delay line, the first, second, third and fourth low-pass filters, the inputs of which are the outputs of the first, second, third and fourth multipliers, respectively, the first and second subtracters, the inputs of the first subtractor are the outputs of the first and second low filters frequencies, the inputs of the second subtractor are the outputs of the third and fourth low-pass filters, the first and second amplifiers with automatic gain control, the outputs of which are the outputs of the device, the signals from which upayut servo system to the actuators for eliminating the error, further having a fifth multiplier whose output module formed product of measured values mismatches | y · z _{MOD MOD} | channels Y and Z, that is, the estimated error value, the inputs of which are connected to the outputs of the subtracters, the first and second functional converters, which increase the modules of the measured values of the mismatch in each channel by the value of the estimated error value | y _meas · z _meas |, the first inputs of the functional converters are connected to the output of the multiplier, the second inputs are connected to the outputs of the first and second subtracters, respectively, the outputs of the functional converters are connected to the inputs of the first and second amplifier with automatic gain control accordingly.

The salient features reflected in the claims are: a new method for determining the mismatch, which additionally calculates the estimated error value of the measured mismatch values y _ISM and z _ISM over two channels as the product modulus δ ^* = | y _ISM · z _ISM | and increase the signal modules of the measured mismatch values in each channel | y _meas | and | z _meas |, by the estimated error value δ ^* , and the elements of the device are a multiplier, which forms the estimated error value and two functional converters that increase the modulus of the measured error value of each channel by the value of the estimated error value.

The technical result of the invention is achieved by taking into account the error of measurement of the mismatch caused by the interdependence of the channels when using the new method and new elements of the device and new connections in the device circuit.

The structural diagram of the tracking system is presented in figure 1; figure 2 is a drawing illustrating the formation of the correlation function of the tracking system in the presence of a mismatch in only one channel; figure 3 is a drawing illustrating the formation of the correlation function of the tracking system during the joint operation of two channels (if there is a mismatch in both channels).

Description of the device. The video signal from the vidicon is sent to the video amplifier 1 and then to the threshold device 2, from the threshold device, the binary image is sent to the standard pulse generator 3; reduced to pulses of the same duration, the contour image is fed to the delay line 4, from where it enters the recording unit 5 and four multipliers 8, 9, 10, 11; the recording unit 5 at the commands of the control unit 6 periodically provides an image for overwriting the standard in the memory unit 7; in four multipliers 8, 9, 10, 11, the reference images shifted by values of ± T and ± τ are multiplied by the current image coming from the delay unit 4; Multiplication results are integrated in low-pass filters 12, 13, 14, 15 and fed to subtractors 16, 17, from which signals proportional to the measured mismatches of the current image relative to the reference are fed to a multiplier 18, configured to generate the absolute value of the product, the output of which is formed estimated error value | y _meas · z _meas | and on the functional converter 19, 20, which receives the estimated error value from the multiplier 18; functional converter 19 increases the modulus of the measured value of the mismatch on the channel Y by the estimated error value sign (y _meas ) · (| y _meas | + | y _meas · z _meas |) and the functional converter 20 increases the module of the measured value of the mismatch on the channel Z by the estimated value errors sign (z _meas ) · (| z _meas | + | y _meas · z _meas |) processed in the functional converters 19, 20, the signals are fed to amplifiers with automatic gain control 21, 22 and further to the servo drive to eliminate the mismatch.

The device operates as follows. The video signal from the Vidicon through the video amplifier 1 is fed to the threshold device 2, the output of which is generated a binary signal: one if the video signal is greater than the threshold value and zero if less. From the output of the threshold device 2, a binarized image of the tracking object is fed to a standard pulse generator 3, at the output of which pulses are generated with the same duration τ equal to the period of the synchronizing pulses. The delay line τ _and / 2 4 compensates for the systematic shift of the memory frame due to time quantization, in addition, the image is digitized by logical multiplication of the pulses of the contour of the tracking object and synchronizing pulses. The recording unit 5 by the commands of the control unit 6 periodically overwrites the reference image. From the output of the recording unit, the image in the form of an array of zeros and ones goes to the memory unit 7, where it is stored as a reference (reference) image. In multipliers 8, 9, 10, 11, the reference images shifted by the values ± T and ± τ are multiplied by the current image processed in the same way as the reference image from the output of the delay line 4. The low-pass filters 12, 13, 14, 15, 16 summarize the product results. Subtracting devices 16, 17 implement the differential principle of calculating the mismatches (form direction finding characteristic). From the subtracting devices 16, 17, the signals are fed to the multiplier 18 to form the estimated error value | y _meas · z _meas | and two functional converters 19, 20, which receive the estimated error value from the multiplier 18. Functional converter 19 increases the modulus of the measured value of the mismatch on channel Y by the estimated error value sign (y _meas ) · (| y _meas | + | y _meas · Z _meas |), and functional converter 20 increases the modulus of the measured value of the mismatch on channel Z by the estimated error value sign (z _meas ) · (| z _meas | + | y _meas · z _meas |). Next, the signals are amplified in amplifiers with automatic gain control 21, 22 and are fed to the servo drive to eliminate the mismatch.

Information sources

1. Melik-Shakhnazarov A.M., Markatun M.G. Digital measuring systems of correlation type. M .: Energoatomizdat, 1985, p. 53-60 (prototype).

2. Integrated sighting and navigation system PNS-24M / ed. Ganulich A.K., Sidorina V.M. Part II. Laser-television sighting system ″ Kayra-24 ″. M .: VVIA them. prof. N.E. Zhukovsky, 1980, S. 60-67 (prototype).

Claims (2)

1. A method for measuring the mismatch in two-dimensional tracking systems, based on the construction of differential correlation functions, when the fixed time values ± T and ± τ shifted by the values of the reference images of the tracking object along the channels Y and Z, respectively, are multiplied by the current image, and the result is integrated, thereby thereby forming the correlation functions and subtracting the differential correlation functions for both channels, which are signals proportional to the measured mismatches y _ism and z _ism in two channels, respectively, characterized in that it further computes the estimated error value of the measured values of the mismatch y _ISM and z _ISM for the two channels as the modulus of their product δ ^* = | y _ISM · z _ISM | and increase the signal modules of the measured mismatch values in each channel | y _meas | and | z _rev | by the estimated error value δ ^* . 2. A device for measuring the mismatch in two-dimensional tracking systems, containing a video amplifier, the input of which is the input of the device, a threshold device, the input of which is the output of the video amplifier, a standard pulse generator, the input of which is the output of a threshold device, a delay line, the input of which is the output of the standard pulse generator , a control unit, to the input of which synchronizing pulses are received, a recording unit, whose inputs are the output of the control unit, whose commands overwriting the reference image and the first output of the delay line, the memory block of the reference image, made with the possibility of forming shifted by a fixed value ± T and ± τ image standards on channels Y and Z, respectively, where T is the parameter of the image shift on channel Y, and τ - the parameter of the image shift along the channel Z, the input of which is the output of the recording unit, the first, second, third and fourth multipliers, the first inputs of which are the corresponding outputs of the memory block of the reference image and the second inputs mi - the second output of the delay line, the first, second, third and fourth low-pass filters, the inputs of which are the outputs of the first, second, third and fourth multipliers, respectively, the first and second subtracters, the inputs of the first subtractor are the outputs of the first and second low-pass filters, the inputs the second subtractor - the outputs of the third and fourth low-pass filters, the first and second amplifiers with automatic gain control, the outputs of which are the outputs of the device, the signals from which are fed to the drives system for eliminating the mismatch, characterized in that it additionally has a multiplier, the output of which is formed by the module of the product of the measured values of the mismatch | y _meas · z _meas | on channels y and z, i.e. the estimated error value, the inputs of which are connected to the outputs of the subtractors, the first and second functional converters, which increase the modules of the measured values of the mismatch in each channel by the estimated error value | y _meas · z _meas |, the first inputs of the functional converters are connected to the output of the multiplier, the second inputs connected to the outputs of the first and second subtracters, respectively, the outputs of the functional converters are connected to the inputs of the first and second amplifier with automatic gain control laziness, respectively.

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