RU2694888C1 - Device for tracking object automatic tracking device - Google Patents

Abstract

FIELD: physics.

SUBSTANCE: invention relates to systems similar to radar tracking systems operating in the optical wave range, in particular to a tracking object automatic tracking device, and can be used in sensors of robotic systems, for example in robotic systems of agriculture. Device for automatic tracking of tracking object comprises video amplifier, threshold device, standard pulse generator, delay line, recording unit, control unit, parameter measuring unit T, measurement unit T_av, a memory unit, four multipliers, four low-pass filters, two subtractors, two amplifiers with automatic gain control, signals from which are sent to servo drive drives to eliminate mismatch, all said devices are connected to each other in a certain manner.

EFFECT: technical result consists in improvement of accuracy of measurement of mismatch between current and required positions of tracking object image in channel Y.

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Description

The technical field to which the invention relates.

The invention relates to systems similar to radar tracking systems in which the type of waves is insignificant, in particular, to a device for automatically tracking an object of tracking and can be used in automatic two-dimensional television tracking systems that measure the mismatch in two coordinates, namely to television viewfinders, for example , in robotic farming systems.

The level of technology

A known real-time optical correlator Ven der Lugt on a photorefractive crystal of gallium arsenide GaAs, in which to enhance the reliability of recognition, the processed images are delineated (see US Pat. No. 5,150,228, IPC G03B 1/16, published on 09.22.1992).

The disadvantages of the analogue - correlator are: complex optical design, sensitivity to vibration, which does not allow its use in mobile robotic systems.

There is a method of measuring the error in automatic tracking devices, based on the differential method for constructing the direction finding characteristics of two channels, in which two values of the correlation function are calculated in each channel: K _1,2 (X) = ∫ _A B (xX) ⋅B (x ± ΔX ) dX, where x is the argument of the reference (reference) function B (x), and X is the measured magnitude of the bias (mismatch) of the current function B (xx) relative to the reference B (x), ΔX is the fixed offset value of the function B (x ), with advance B (x-ΔX) and delay B (x + ΔX), used to calculate the correlation functions K ₁ (X) and K ₂ (X), allowing to construct the direction-finding characteristics ΔK (X) = K ₂ (X) -K ₁ (X) in automatic tracking devices for determining the sign (direction of displacement) and magnitude (modulus) mismatch X. Actuators on the calculated sign and value eliminate the mismatch in the desired direction and the calculated value (see Melik-Shakhnazarov AM, Markatun MG, Digital measurement systems of correlation type. - M .: Energoatomizdat, 1985, p. 53-60).

The disadvantage of this method is the hypothesis about the similarity of signals in the measurement channels, however, if different channels are processed in each channel, they require different processing algorithms.

The prototype device closest to the technical essence is known for automatic tracking of the tracking object with two independent identical channels for calculating mismatches U _Y and U _Z consisting of a video amplifier, a threshold device, a generator of standard pulses, a delay line, a recording unit, a parameter measuring unit T, a unit memory, four multipliers, four filters, two subtractors and two amplifiers with automatic gain control, while the analog input of the video amplifier is the input of the device a, the input of the threshold device is the output of the video amplifier, the input of the generator of standard pulses is the output of the threshold device, the input of the delay line is the output of the generator of standard pulses, the input of the control unit receives synchronizing pulses, the inputs of the recording unit are the output of the control unit and the first output of the delay line, the input of the block measuring parameter T is the output of the recording unit, the inputs of the memory unit are the output of the measuring unit parameter T and the output of the recording unit, the input of the memory unit About the image is the output of the recording unit, the first inputs of the first, second, third and fourth multipliers are the corresponding outputs of the reference image memory block and the second inputs are the second output of the delay line, the inputs of the first, second, third and fourth low-pass filters are the first, second, the third and fourth multipliers, respectively, the inputs of the first subtractor are the outputs of the first and second low-pass filters, the inputs of the second subtractor — the outputs of the third and fourth filters are low their frequencies, the inputs of the first and second amplifiers with automatic gain control are the outputs of the first and second subtractors, respectively, the outputs of the amplifiers with automatic gain control are the outputs of the prototype device, the signals from which go to the tracking system drives to eliminate the error (see pat Of the Russian Federation №2284552, cl. G01S 13/66, publ. September 27, 2006).

The disadvantage of this known prototype device is an error in determining the magnitude of the mismatch on the Y channel, which arises due to the assumption that the tilt angle γ of the contour object’s lines to the television line is the same (Fig. 4.a or 4.b or 4.c) when forming the digital contour object tracking. The real digital contour of the tracking object can form lines with different angles of inclination γ _i , leading to different values of the parameter T _i (Fig. 5). Not taking into account the multiplicity of T _i values of the heights of the impulse packets and the shift of the reference digital contours of the tracking object over the frame, measured in channel Y, by the received value, for example, f _op (t ± T ₀ ) _; when T = T ₁ or T = T ₂ leads to non-linearity of the actual direction-finding characteristics (Fig. 2.a.6 and 2.b.6) and, as a result, to a decrease in the accuracy of determining the error on the Y channel and, accordingly, reducing the reliability tracking object tracking.

DISCLOSURE OF INVENTION

An object of the invention is to improve the accuracy of determining the mismatch on the Y channel and, accordingly, the tracking object tracking reliability by calculating the average value of T _cp = ∑N _i T _i / ∑N _i , which takes into account the multiplicity of values of the parameter T _i - -high pulse packets of the digital contour of the tracking object measured pulse number n _i in each of N _i - pulse packets (Figs 4 and 5,.) forming the contours of the digital tracking of the object, which is variable depending on the angle γ _i - tilt follow the contour of the object Ia, that allows to form DF characteristic ΔK (Y) Y channel differential method (FIG. 2.b.4 and b.5) as close as possible to a linear (FIG. 2.b.6).

The technical result of the invention is to improve the accuracy of determining the error on the channel Y and, accordingly, the reliability of tracking object tracking.

The technical result is achieved using a device for automatic tracking of a tracking object containing a video amplifier whose analog input is a device input, a threshold device whose input is a video amplifier output, a standard impulse generator whose input is a threshold device output, a delay line whose generator output is standard pulses, the control unit, the input of which receives the synchronizing pulses, the recording unit, the inputs of which are Exit control unit, on command which is produced overwriting reference digital contour tracking object, and a first output of the delay line unit measuring a parameter T that calculates a height of packets of pulses T _i reference digital loop tracking the object through the channel Y, the input of which is the output of the recording unit, a memory unit reference digital contour of the tracking object, made with the possibility of forming standards of the digital contour of the tracking object shifted by fixed values ± T and ± τ through the Y and Z channels, respectively, dd the parameter T is the height of the pulse packet of the reference digital contour of the tracking object over the Y channel, and the parameter τ is the pulse length over the Z channel generated by the standard pulse generator, the memory block inputs are the output of the parameter measurement block T and the output of the recording block, first, second, third and the fourth multipliers, the first inputs of which are the corresponding outputs of the memory block of the reference digital circuit of the tracking object and the second inputs are the second output of the delay line, the first, second, third and fourth low-pass filters, in which are the outputs of the first, second, third and fourth multipliers, respectively, the first and second subtractors, the inputs of the first subtractor are the outputs of the first and second low-pass filters, the inputs of the second subtractor are the outputs of the third and fourth low-pass filters, the first and second amplifiers with automatic adjustment amplifiers whose inputs are the outputs of the first and second subtractors, respectively, the outputs of amplifiers with automatic gain control are the outputs of the device, the signals from which Likewise, they arrive at the servo system drives to eliminate the mismatch, the proposed device additionally has a block for calculating the average value T _{c of the} parameter T - the average height of the pulse packets of the reference digital circuit through channel Y, whose input is connected to the output of the measuring unit of the parameter T, and the output is the first input of the block the memory of the reference digital contour, made with the possibility of forming shifted standards of the digital contour of the object of tracking along the channel Y by the calculated value ± T _cf.

The essential feature reflected in the claims is the element of the device for automatic tracking of the tracking object — a calculation unit T _av — average height T, packets N _i — pulses of the reference digital circuit f _op (t).

The technical result of the invention has been achieved by taking into account the calculated average value T _{cf of the} set T _{i of the} parameter T - heights N _{i of the} impulse packets of the reference digital circuit, thanks to the use of a new block and new connections in the device circuit for automatically tracking the tracking object.

Brief Description of the Drawings

FIG. 1 shows a block diagram of a tracking system, a general view;

in fig. 2 - graphs illustrating the formation of the direction-finding characteristic of the tracking system on the Y channel;

in fig. 3 - scan television signal taken from the generator of standard pulses;

in fig. 4 - scan of a television signal after quantization in time taken from the delay line;

in fig. 5 - real digital contours of the object of tracking with different angles of inclination.

The implementation of the invention

The device for automatic tracking of the tracking object, measuring the mismatches of Y and Z via Y and Z channels, respectively (Fig. 1), contains a video amplifier 1, the analog input of which is the input of the device for automatic tracking of the tracking object, the threshold device 2, the input of which is output video amplifier 1, the generator 3 standard pulses, the input of which is the output of the threshold device 2, the delay line 4, the input of which is the generator output 3 standard pulses, block 5 records, the inputs of which o are the first output line 4 delay and the control unit 6, the output of which commands performed dubbing reference digital circuit object tracking f _op (t) (Figure 2), the input of which receives the clock pulse (SI), a measuring unit 7, a parameter T, computes height T _{i of} packets N _i pulses of the reference digital contour of the tracking object f _op (t) on channel Y and the number of packets N _i with height T _i whose input is the output of recording unit 5, and the output is connected to block 8 for calculating the average value of the parameter T - average height T _cf package s of pulses of the reference digital contour of the tracking object f _op (t) on channel Y, the output of which is the first input of block 9 of the memory of the reference digital contour of the tracking object f _op (t), configured to form shifted reference digital standards of the tracking object on the calculated Y value ± Tcp, and ± τ standards of the digital contour of the tracking object on channels Y and Z, respectively, where the parameter τ is the period of the synchronization pulses (SI) on the Z channel, generated by the generator 3 standard pulses, the inputs of the block and 9 memories are the outputs of block 8 of the computation T _cf and block 5 of the record, and the outputs are the first inputs of the first f _op (t + T _cp ), the second f _op (tT _cp ), the third f _op (t + τ) and the fourth f _op (t-τ) multipliers 10, 11, 12, 13, respectively, and their second inputs - the second output of the delay line; the first, second, third, and fourth low-pass filters 14, 15, 16, 17, respectively, whose inputs are the outputs of the first, second, third, and fourth multipliers 10, 11, 12, 13, respectively; The first 18 and second 19 subtractors, the inputs of the first subtractor 18 are the outputs of the first and second low-pass filters 14, 15, respectively, the inputs of the second subtractor 19 are the outputs of the third and fourth low-pass filters 16, 17, respectively, the first 20 and second 21 amplifiers with automatic gain control, whose inputs are the outputs of the first and second subtractors 18, 19, respectively, the outputs of amplifiers with automatic gain control 20, 21, respectively, are the outputs of the device for automatic tracking EKTA tracking values mismatches U _Y U _Z and with actuators which act on the servo system (FIG. 1, not shown) to eliminate the error, the method further comprises a calculation unit 8 T _cp, at whose output is generated the value T _cp = ΣN _i T _i / ∑N _i (N _i is the number of packets with height T _i measured by the number of pulses n _i in the packet N _i , ∑N _i is the total number of packets of pulses) on channel Y, whose input is connected to the output of the parameter measuring unit 7 T _i and counting the number of packets N _i, and the output is the first input of the storage unit 9 ref nnogo digital object contour tracking f _op (t), it configured to generate a shifted standards f _op (t + T _cp) and f _op (tT _cp), respectively, the digital tracking loop object on channel Y on the computed value ± T _Wed.

Device for automatic tracking object tracking works as follows.

The video signal from the vidicon (not shown in Fig. 1) is fed to the video amplifier 1 and then to the threshold device 2, at the output of which a binary signal is formed - rectangular pulses with different duration. From the threshold device 2, the binary image is fed to the generator 3 standard pulses, at the output of which pulses are formed with the same duration τ equal to the repetition period of the sync pulses; the image of the tracking object, created by casting the binary image to pulses of the same duration τ, is fed to the delay line 4, as a result, the analog circuit of the tracking object is formed (Fig. 3). Line 4 of the delay compensates for the systematic shift of the image due to time quantization, in addition, the logical multiplication of the pulses of the analog circuit of the object of tracking and synchronizing pulses converts the analog circuit of the object of tracking into sets of meanders forming the digital contour of the object of tracking (Fig. 4). As a result, the digital contour of the tracking object f _tech (t) is obtained with raster distortions in the form of pulse packets with a constant width τ and variable heights T _i depending on the angles of tilt γ _i to the television line (Fig. 4.a, b, c) c digital contour object tracking. The binary code representing the digital contour of the tracking object (Fig. 4) enters the recording unit 5 and four multipliers 10, 11, 12, 13, respectively. The recording unit 5 forms a digital contour of the tracking object in the form of an array of zeros and ones (Fig. 4), which enters the memory block 9 and the commands of the control unit 6 periodically record the digital contour of the tracking object stored as a reference (reference) digital contour of the tracking object f _op (t) (Fig. 2, pos. 1), and in block 7 of measuring the parameter T to determine the heights T _{i of} packets of pulses by counting the number of n _i pulses in a packet and the number of these packets N _i via channel Y, which are fed to the block 8 calculate the average height T _cf packet impulse owl, the output of which is the input of memory block 9, in which T _{cf is} taken into account when forming shifted reference digital circuits f _op (t ± T _cp ) of the tracking object on channel Y (Fig. 2.b, pos. 2, 3), thus an adaptation of the tracking system to changes in the angles γ _{i of the} slope of the lines in the digital contours of the tracking object (Figs. 3, 4, 5) and the construction of a tunable direction-finding characteristic via the Y channel (Fig. 2.b.6) is achieved. The principle of the formation of the direction-finding characteristics is the same for both channels Y and Z (Fig. 1). Reference (reference) digital contours of the tracking object shifted in memory block 9 by the calculated value ± T _{cf of the} parameter T via the Y channel: f _op (t + T _cf ), f _op (t-T _cf ) and ± τ is the constant value of the parameter t on the Z channel: f _op (t + τ), f _or (t-τ) in four multipliers 10, 11, 12, 13 are multiplied by the processed, like the reference, current digital contour of the tracking object f _tech (t) coming from output line 4 delay. The low-pass filters 14, 15, 16, 17 produce the summation of the results of the product, thereby calculating the values of the correlation functions K ₁ (Y) = ∑f _op (tT) f _tech (t), K ₂ (Y) = f _op ( t + T) ⋅f _tech (t) in the channel Y (Fig. 2.b, pos. 4, 5) and K ₁ (Z) = Σf _op (t-τ) ⋅f _tech (t), K ₂ (Z) = ∑f _op (t + τ) ⋅f _tech (t) in channel Z. Subtractors 18, 19 implement the differential principle of determining mismatches, calculating the differential correlation functions ΔK (Y) = K ₂ (Y) -K ₁ ( Y) in the Y channel (Fig. 2.b, pos. 6) and ΔK (Z) = K ₂ (Z) -K ₁ (Z) in the channel Z, thereby forming the Y direction finding channel characteristics and device for automated Z eskogo support tracking object. The signals U _Y and U _Z , proportional to the mismatch Y and Z in channels Y and Z, respectively, between the reference f _op (t) (required) and the current f _tech (t) digital circuits of the object of tracking, go to the amplifiers 20, 21 with automatic by adjusting the gain, respectively, from the outputs of which are fed to the drives of the tracking system (not shown in Fig. 1) to eliminate the error.

The effectiveness of the proposed solution is verified and confirmed by computer simulation.

The present invention compared with the prototype and other known solutions by taking into account the calculated average value T _{cf of the} set T _i parameter T - the heights of the pulse packets N _{i of the} reference digital contour of the tracking object in channel Y, implemented in the new unit, and the new connections in the device circuit, has the advantage of: improving the accuracy of determining the mismatch of the channel Y and, as a consequence, the reliability of tracking the object tracking.

Claims (1)

A device for automatic tracking of a tracking object containing a video amplifier whose analog input is the device input, a threshold device whose input is the video amplifier output, a standard pulse generator, the input of which is the output of the threshold device, a delay line whose input is the output of the standard pulse generator, the control unit whose input receives synchronizing pulses, a recording unit whose inputs are the output of a control unit, on commands of which oizvoditsya overwriting reference digital contour tracking object, and a first output of the delay line unit measuring a parameter T that calculates a height of packets of pulses T _i reference digital loop tracking the object through the channel Y, the input of which is the output of the recording unit, the memory reference digital contour tracking object executed with the possibility of forming standards of the tracking object shifted by fixed values ± T and ± τ through the Y and Z channels, respectively, where the parameter T is the height of the pulse packet of the reference the digital contour of the tracking object on the Y channel, and the parameter τ is the pulse length on the Z channel generated by the standard pulse generator, the memory block inputs are the parameter measurement block output T and the recording block output, the first, second, third and fourth multipliers, whose first inputs are the corresponding outputs of the memory block of the reference digital contour of the tracking object and the second inputs are the second output of the delay line, the first, second, third and fourth low-pass filters, whose inputs are the outputs of the first, second , the third and fourth multipliers, respectively, the first and second subtractors, the inputs of the first subtractor are the outputs of the first and second low-pass filters, 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, whose inputs are the outputs of the first and the second subtractors, respectively, the outputs of amplifiers with automatic gain control are the outputs of the device, the signals from which are fed to the servo drives for elimination of the mismatch, characterized in that it is additionally equipped with a unit for calculating the average value T _{cf of the} parameter T - the average height of the pulse packets of the reference digital contour of the tracking object via channel Y, the input of which is connected to the output of the measuring unit of the parameter T, and the output is the first input of the reference memory digital contour of the object of tracking, made with the possibility of forming shifted standards of the digital contour of the object of tracking through channel Y by the calculated value ± T _cf.

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