Detection method of underwater robot and unmanned aerial vehicle and device suitable for implementation of detection method

Abstract

The present invention relates to the field of detection of ferromagnetic underwater objects and other objects of artificial origin. The technical result of the invention is that the detection range of ferromagnetic underwater objects and other objects (such as underwater robots and unmanned aerial vehicles with complex and heterostructures) is increased. The detection method is based on the use of a radiation magnetic ring antenna in two working modes: the first mode is a parameter magnetization mode; the second type is inductive, accompanied by recording parameter modulation and influencing the mechanical force impact channel by means of electro-hydraulic impact. Meanwhile, due to the high penetrating power of the pulsed magnetic field and the mechanical shock physical field, faults of the electronic circuit of the detected object are captured as additional information characteristics through the body shell.

Description

Technical Field

[0001] This invention relates to a method for detecting objects and an apparatus for detecting objects (such as underwater robots and drones).

[0002] This invention relates to the field of detecting ferromagnetic underwater objects and other man-made objects, particularly underwater robots and drones that are prevalent in the modern world. Background Technology

[0003] The most difficult problem is detecting stationary objects. These are so-called underwater "bookmarks"—robotic capsules that are deployed underwater for weeks, months, or years, activated by signals, and then run and activate one or more functions after surfacing or submerged.

[0004] Inspecting these underwater robotic capsules is an extremely urgent task to ensure the safety of seaports and river ports, ships, and coastal infrastructure.

[0005] A method for detecting underwater acoustic signals of objects in an aquatic environment is known. The method is based on recording underwater acoustic signals reflected from underwater objects [1].

[0006] The drawback of this method is that it is practically impossible to detect stationary underwater objects in the presence of interference, especially due to seabed irregularities.

[0007] For detecting ferromagnetic (and non-ferromagnetic) metallic objects, one induction method is known [2].

[0008] The drawback of this method is its small detection range, which is comparable to the size of the search element (frame antenna).

[0009] The closest invention to the claimed invention is a magnetic force measurement detection method that allows the detection of ferromagnetic objects in a variety of environments, including water[3].

[0010] Known magnetic measurement methods allow for recording the spatial distortion of the Earth's magnetic field produced by ferromagnetic objects. Objects whose structures include ferromagnetic elements (body, mechanical, and electrical components) can be detected in any natural environment: deep within seawater and freshwater, clay and sandy soils, ice, etc. The strength of the Earth's magnetic field is 0.34 Oersted at the magnetic equator, 0.66 Oersted at the magnetic poles, and 0.57 Oersted at mid-latitudes (approximately 40 A / m in the SI system).

[0011] The most commonly used device in this field is the magnetometer. Using two magnetic receivers, a device is created to measure the difference in magnetic field induction between two points in space. In this case, the device is called a magnetic gradiometer.

[0012] The drawback of this method is its limited detection range for locally ferromagnetic objects, not exceeding 6-8 meters. These objects typically have dimensions measured in decimeters to meters.

[0013] US 6,335,624 B1 discloses the detection of conductive objects hidden near the seabed surface, such as mines laid near the coast.

[0014] DE 10 2016 112 524 A1 discloses a method for electromagnetic detection and surveying of the water surface to find metallic foreign objects hidden beneath the bottom, particularly for searching for unexploded ordnance.

[0015] US 5,598,152 discloses the detection of underwater objects by creating an electric or magnetic field and measuring its deviation and variation. Magnetic objects change due to their magnetization based on the emitted electric or magnetic field. Non-metallic objects submerged in seawater cause deviations in the created electric or magnetic field by creating "holes" in the conductive pattern of the seawater.

[0016] AU 632320B2 discloses a method for detecting objects immersed in saltwater or brackish water by creating a magnetic field and measuring its deviation and changes. The magnetic field is created in a pulse-like manner, abruptly switching from a substantially stable voltage to at least one other substantially stable voltage.

[0017] RU 2 444 765 C2 discloses a method for detecting underwater objects by generating mechanical vibrations of the target object using a pulsed magnetic field and then detecting the vibrations using a hydroacoustic method.

[0018] US 6,215,734 B1 discloses a projector for generating electro-hydraulic acoustic and pressure waves. This includes an energy source, such as a capacitor, arranged within an electrode assembly of approximately one meter in radius. Larger projectors can be formed by arranging multiple projectors, or even by lining the projectors in a row. Summary of the Invention

[0019] One of the objectives of this invention is to increase the detection range of ferromagnetic underwater objects and other objects, such as underwater robots and drones with complex and heterogeneous structures.

[0020] This objective is achieved through the features of the independent claims. Favorable developments come from the dependent claims.

[0021] The detection of ferromagnetic underwater objects is achieved by introducing an additional impact pulse magnetic field channel. This channel magnetizes the ferromagnetic elements of the object being detected, and the change (increase) in the object's magnetic field is due to remanent magnetization, which is recorded by a magnetic force measurement receiver.

[0022] The detection of ferromagnetic (and non-ferromagnetic) underwater objects is based on the impact of an additional pulse of mechanical force via electro-hydraulic shock and the influence of a harmonic magnetic field from a magnetic frame antenna on the object being detected, and the parametric modulation (“burst”) of the reflected harmonic magnetic field is recorded.

[0023] The electro-hydraulic shock causes a short-term (pulse) change in the distance (r and h) between the search object, the magnetic loop antenna, and the receiver due to the mechanical impact of the electro-hydraulic shock on the metal object being detected.

[0024] This results in a parameter amplitude modulation (“burst”) of the reflected signal of the investigated harmonic magnetic field, which is recorded as an additional information feature by the magnetometer receiver.

[0025] This improves search performance.

[0026] The outer shells (body) of underwater robots and drones are mostly made of ferromagnetic materials. However, the possibility of making them from other materials that do not exhibit magnetism (such as titanium, bronze, brass, etc.) must be considered. Underwater acoustic shock waves generate pulsed overpressure and penetrate the ferromagnetic or non-ferromagnetic shell of the object being tested.

[0027] Inside the housing are the movable and fixed components of the object (robot or drone): electric motors, batteries, electromechanical actuators for the manipulators, mechanical components of the actuator module, and control system devices. Their positions within the housing are connected by fastening elements, pulleys, hinges, and springs.

[0028] The overpressure pulse from the electro-hydraulic shock penetrates the casing and causes a resonant "splash," making the object "shudder."

[0029] The presence of pulsed magnetic fields and mechanical shock fields penetrating the body shell of the object being tested causes partial damage to the function of the electronic circuits inside the object. This alters the operating mode of the electronic circuits and causes characteristic "sudden" changes in the level of reflected signals.

[0030] Therefore, additional information about the objects emerged due to partial damage to the electronic circuits (electromechanical components) of the underwater robots and drones.

[0031] One important direction for increasing the maximum detection depth is to create conditions where the searched object causes a stronger distortion of the Earth's magnetic field. This is achieved through remote parametric magnetization, a special case of parametric localization in semiconductor media.

[0032] In the first approximation, the locally detected object can be replaced by a solid ferromagnetic sphere. In the Earth's uniform magnetic field, the ferromagnetic sphere acts like a magnetic dipole, and its magnetic moment is determined by the following formula:

[0033]

[0034] in,

[0035] R sp – Radius of the ferromagnetic sphere (search object):

[0036] μ1 – Magnetic permeability of the spherical material

[0037] μ0 – the magnetic permeability of the surrounding natural environment.

[0038] (water, soil) and

[0039] H0 is the Earth's constant magnetic field.

[0040] In practice, when searching for local ferromagnetic objects, what is usually measured is not the absolute value of the anomalous magnetic field, but its gradient.

[0041] The maximum detection range for detecting ferromagnetic spheres using a magnetic gradient meter can be estimated using the following formula:

[0042]

[0043] Wherein, min is the field sensitivity T / m of the gradiometer (the distortion of the magnetic field per unit length in space, where B is the magnetic induction intensity).

[0044] actual

[0045] The sensitivity of modern portable magnetic gradient meters is 10. -7 …10 -8 T / m. For a ferromagnetic sphere with a radius of 0.3...0.5m, at a sensitivity of 10 -8 The detection range at T / m is 6...8m.

[0046] The underwater robot located in the water column is mostly made of polycrystalline ferromagnetic material, primarily steel.

[0047] Depending on the chemical composition of the alloy and the geometry of the object, its physical and mechanical properties undergo various structural and phase transformations during magnetization. Figure 2 These changes typically lead to improved efficiency in the devices (including search equipment) used to detect and search for objects such as underwater robots and drones, regardless of their construction principles.

[0048] Therefore, phase transitions typically lead to an increase in the intrinsic magnetic field due to stronger alignment of magnetic domain moments.

[0049] The detection range of a magnetized iron sphere can be estimated using the following expression:

[0050]

[0051] Among them, K dem- is the demagnetization coefficient (0.33 for a sphere).

[0052] H ext - is the magnitude of external magnetization, A / m.

[0053] As can be seen from expression (3), magnetizing the sphere with a pulsed magnetic field with an amplitude of 1 kA / m can increase the detection range by about 80%.

[0054] It should be noted that the duration of the magnetizing pulse can be quite short. For search objects with a wall thickness of 1...10 mm, it is only one-tenth...one-hundredth of a second. Based on shielding theory, this duration is determined by the thickness of the steel's "surface" [4,5]. The short duration of the pulse and the long pause (in units of...tens of seconds) ensure low power consumption in the technical implementation of this method.

[0055] Field experiments were conducted to test the most complex component of the proposed method.

[0056] The detection range of iron for magnetic objects is the same in both fresh and seawater as in soil. Furthermore, in the case of soil, soil moisture has no effect on the detection range. When searching in water, the magnetometer is mounted on a non-magnetic floating vehicle (rubber boat). This vehicle does not contain any ferromagnetic elements (supports, nails, spikes, etc.).

[0057] The experimental setup generates a pulsed magnetic field with an amplitude of 500...700 A / m at the location of the search object, lasting for 20 ms. The search object is:

[0058] • Steel balls with diameters of 5cm and 10cm (see search objects);

[0059] • A steel pipe with a diameter of 10cm and a length of 30cm (underwater robot model).

[0060] The MBI-2 portable magnetometer, with a sensitivity of up to 10⁻⁷ T / m, was used as the search instrument.

[0061] Measurements were also conducted in fresh water (ε = 80, n = 10⁻² S / m) in a pond 2.5 m deep. The detection range of the object was the same as in air. The MBI-2 magnetometer was placed on a rubber boat.

[0062] Exposure to H ext Ferromagnetic objects under long-range magnetization of ≈500...700 A / m were detected at distances 1.5...2 times higher than the limits of the MBI-2 magnetometer.

[0063] As described above, this invention proposes a method for remotely magnetizing a search object to increase the detection range of ferromagnetic objects using magnetic force measurement. However, this method can only detect ferromagnetic objects.

[0064] The novelty of this invention (the method according to claim 2) lies in that it not only increases the detection range for ferromagnetic underwater objects, but also increases the detection range for any metallic search object. It can also perform identification and determine the identification range.

[0065] The method claimed to be protected additionally includes two channels: the first is a pulsed mechanical force impact channel of electro-hydraulic shock, and the second is an information influence channel of the harmonic magnetic field from the magnetic loop antenna on the object being detected, and records the parameter modulation (“splash”) of the reflected harmonic magnetic field.

[0066] The search object is illuminated using a low-frequency magnetic field, and the field reflected from the object's surface is recorded. Additionally, a pulsed mechanical force is applied using an electro-hydraulic impact device (EHU).

[0067] The searched object has a fairly complex structure, so the reflection pattern of the secondary magnetic field from the real object also has a complex needle-like shape. This enhances the amplitude parameter modulation effect of the signal during back reflection because the phase in the reflected harmonic field also changes. Therefore, the effect of parameter modulation is significantly enhanced when a phase-sensitive receiver is used.

[0068] Considering the above, the secondary (reflected) magnetic field of the search object is determined by the following expression:

[0069]

[0070] in,

[0071] M is the magnetic moment of the radiating frame antenna.

[0072] 0 = 4π·10 -7 H / m

[0073] r sp It is the radius of the object being searched (a sphere), in meters.

[0074] h is the distance between the search object and the magnetic loop antenna, m

[0075] r is the distance between the search object and the receiver of the reflected magnetic field, m

[0076] D is a function that describes the abnormally low-frequency magnetic field on the surface of an object [6].

[0077] Since the distance to the object being detected is not large and the frequency used is quite low (hundreds of Hz to thousands of Hz), the loss of the harmonic LF magnetic field in seawater (ε=80, n=4S / m) is insignificant.

[0078] Under the influence of underwater acoustic impacts from the EHU device, the distances (r and h) between the search object, the magnetic frame antenna, and the receiver undergo short-term (pulse) changes. This results in parametric amplitude modulation (“burst”) of the reflected signal. Simultaneously, characteristic resonant oscillations also occur. Each object type has its own vibration spectrum, allowing for its identification. Furthermore, optimal filtering of the received signal can be performed, increasing the receiver's sensitivity and thus expanding the detection range.

[0079] The distance to the target object can be estimated by measuring the propagation time of the underwater acoustic impact from the EHU device to the target object[7]. In this case, the steady-state value of the impact velocity in the water is known to be 1485 m / s.

[0080] Practice has shown that stationary robots—"bookmarks" in sleep mode—can hide within the silt and bottom sediment layers of the seabed topography, making them extremely difficult to search. Mechanical vibrations are accompanied by significant losses as they travel through these layers in the form of underwater acoustic waves.

[0081] In the claimed invention (as described in claim 3), it is suggested to use the deep penetration properties of the magnetic field (which can propagate equally in soil and seawater) and the force of the shock wave as a mechanical effect.

[0082] The deep penetration characteristics of pulsed magnetic fields and mechanical shock fields through the outer shell of the object being tested cause partial malfunctions in the internal electronic circuitry, resulting in characteristic "sudden" changes in the reflected signal. Therefore, additional information indicators may appear, even related to partial damage to the electronic circuitry of underwater robots and drones. The required parameters for the pulsed magnetic field are listed below:

[0083] In the first approximation, these locally searched objects can be represented as hollow spheres or elongated ellipsoids containing internal electronic components. Typical radio circuit faults caused by induced voltages are known to become apparent when the pulsed magnetic field strength exceeds 100 A / m [8,9]. The amplitude and shape of the induced voltage in the circuit are primarily determined by the following factors:

[0084] • Magnetic field strength, rise and fall time;

[0085] • The geometric dimensions of the circuit outline;

[0086] • Component identification;

[0087] • Mutual alignment of circuit and magnetic field vectors;

[0088] • Electrical mode (supply voltage, sensitivity to input signal polarity reversal);

[0089] • The structural arrangement of circuit mounting components relative to the device's metal housing.

[0090] Pulsed magnetic fields penetrate shielding structures through two mechanisms: the field diffuses through the wall due to the non-ideal conductivity of the shielding structure; the field penetrates through the aperture.

[0091] It is known that a pulse signal can be represented as the sum of harmonic components. In a strict environment, in order to determine the penetration of harmonic electromagnetic fields into the interior of a solid conductive shield, a boundary problem is proposed: Maxwell's equations are considered in three regions (exterior, interior, and the wall of the shield). For the simplest shield structure (shell), an analytical expression for the transfer function is obtained, which is the ratio of the field penetrating the shield to the external field

[10] . Based on the transfer function, the impulse response of the barrier can be determined by the inverse Fourier transform. However, even the frequency dependence of the transfer function of the simplest barrier is still quite complex, and it is impossible to obtain an expression for the barrier impulse response in analytical form with a finite number of terms

[11] .

[0092] A simplified solution to the problem of pulsed magnetic fields penetrating a barrier through a metallic casing can be achieved using the average frequency of the video pulse spectrum. This allows for the application of well-established insights from the theory of harmonic electromagnetic field propagation through conductive media.

[0093] The propagation process of harmonic magnetic fields in a conductor is described by the following expression:

[0094]

[0095]

[0096] h is the penetration depth of the field into the metal, m

[0097] μ0 = 4π·10⁻⁷ - permeability in vacuum, H / m

[0098] The average frequency of the video pulse spectrum is:

[0099]

[0100] Where ΔT is the pulse duration of the magnetic field.

[0101] in turn: (8)

[0103] ω sur =2πF sur ,Hz

[0104] The attenuation coefficient Ka is the magnetic field H within the thickness of the conductor (metal). f The ratio of the amplitude of the field to the amplitude H1 at its surface (before penetrating the metal).

[0105] Currently, the outer shell (hull) of small underwater devices (robots and drones) is typically made of titanium rather than steel. This is due to two factors:

[0106] Titanium has higher strength than steel;

[0107] • It lacks magnetic properties, which makes it more difficult to detect.

[0108] The wall thickness of the shell is typically a few millimeters, ranging from 1 to 10 mm.

[0109] Figure 1 illustrates the dependence of the pulsed magnetic field attenuation coefficient on these pulse durations. A decrease in duration increases the average frequency of the spectrum, which leads to increased field attenuation within the thickness of the metal (titanium).

[0110] Properties of titanium in calculations:

[0111] • Conductivity γ=2·10 7 S / m,

[0112]

[0113] Figure 1. Dependence of the attenuation coefficient of the pulsed magnetic field in metal on the pulse duration. Shell material (barrier) – titanium.

[0114] • Relative permeability equals 1 (paramagnetism).

[0115] Figure 1 shows that when the magnetic field pulse duration exceeds 1 ms and the titanium shell thickness is 1 mm to 10 mm, the loss is insignificant because the field penetrates into the barrier. This allows the use of pulsed magnetic fields to disable the internal modules of various underwater devices that incorporate electronic components in their design.

[0116] By combining an electro-hydraulic shock or electro-hydraulic device (EHU) or a device that generates electro-hydraulic shock pulses, pulsed magnetic fields with an intensity of 100 A / m or higher can be generated. However, in this case, the high-voltage capacitor bank is not connected to the spark gap, but to a frame antenna with a large diameter (several meters).

[0117] The pulsed mechanical force generated by electro-hydraulic impact also has high penetrating power, capable of penetrating both ferromagnetic shells and the walls of objects made of other materials.

[0118] It is known that the outer shell (body) of most underwater robots and drones is made of ferromagnetic materials. However, the possibility of making them from other materials that do not exhibit magnetism (such as titanium, bronze, brass, etc.) must be considered.

[0119] The underwater acoustic shock wave generates pulse overpressure and penetrates the non-ferromagnetic outer shell of the object being tested.

[0120] The movable and fixed components of an object (robot or drone) are housed within the main body housing: electric motors, batteries, electromechanical actuators for manipulators, mechanical components for control modules, and control system devices. Their positions within the main body housing are connected by fastening elements, pulleys, hinges, and springs.

[0121] The overpressure pulse from the electro-hydraulic shock penetrates the interior of the casing and causes a resonant "splash," making the object "shudder."

[0122] The electronics of underwater robots and drones can be deactivated by shock waves [12–14]. This impact can be achieved via electro-hydraulic shock. This process is characterized by the absence of intermediate steps in the conversion of electrical energy into mechanical energy. The pressure in the discharge channel between high-voltage electrodes (characteristically ranging from a few centimeters to tens of centimeters) can reach tens of thousands of atmospheres. The voltage values ​​are typically in the range of 10 kV to 100 kV. In this case, the duration of the electrical discharge itself is typically several microseconds to tens of microseconds. Such a time is typical for the explosion of small charges (tens of grams to several kilograms) of ordinary TNT.

[0123] The expression for estimating the pressure at the front of the shock wave generated in water by an electro-hydraulic unit (EHU) has the following form:

[0124]

[0125] Where C- is the capacitance of the capacitor bank, F

[0126] U – is the voltage across the capacitor, V

[0127] η is the conversion coefficient between electrical energy of discharge and mechanical energy of shock wave (0 < η < 0.35).

[0128] Figure 2 shows the pressure at the front of the shock wave generated by the EHU device as a function of distance (at η = 0.25).

[0129]

[0130] Figure 2 shows the dependence of pressure at the wavefront generated by the EHU device on distance.

[0131] The decommissioning of underwater objects is possible in two situations:

[0132] • Damage to the metal casing (titanium, steel);

[0133] • Disabling all electronic components inside the casing.

[0134] In the first case, the pulse pressure should be several hundred atmospheres, and in the second case, it should be several tens of atmospheres (approximately).

[0135] Analysis of modern underwater robots and drones reveals the presence of various configurations of underwater acoustic sensors in their orientation and targeting systems. Essentially, sensitive underwater acoustic sensors are used, and these sensors are manufactured as an integral part of the outer shell.

[0136] The fragile underwater acoustic receiver sensor may fail when the operation of the input sensitive amplifier is interrupted due to the large pulse voltage generated by the piezoelectric sensor.

[0137] However, when applying electro-hydraulic pressure pulses and pulsed magnetic fields to a conventional object—the robotic capsule—to deactivate the hydroacoustic and magnetic orientation and aiming sensors, it must be clear that in sleep mode, the sensitive sensors are inactive, the electronic circuitry is off, and protective devices are in place for environmental contact sensors and electronics. In this respect, failure of the hydroacoustic and magnetic orientation sensors in the robotic capsule aiming system is highly unlikely.

[0138] Therefore, in practice, an important situation is that the underwater acoustic shock wave penetrates the metal shell of the body.

[0139] The actual consideration is a metal plate located in water. It is known that the pressure in the incident wave varies exponentially. Taking some simplifications (assuming the shock wave propagates along the outer shell and structural elements), the pressure behind the metal plate can be determined using equations [12-14]:

[0140]

[0141] Wherein, P - density of the plate material,

[0142] δ - Plate thickness;

[0143] y - Complex parameter coefficients;

[0144] p0 is the density of water;

[0145] c0 is the speed of sound in still water;

[0146] It simplifies the distance.

[0147] As shown in Figure 3, the protective performance of the metal plate is not significant when placed in water. The maximum pressure reduction behind the barrier does not exceed 20%.

[0148]

[0149] Figure 3 shows the pressure as a function of time in the shock wave passing behind the metal plate.

[0150] Therefore, almost all the energy of the mechanical force generated by electro-hydraulic impact acts on the shell and internal structure of the object being tested.

[0151] The following conclusions can be drawn.

[0152] The above enables the detection of ferromagnetic objects as well as objects whose shells are made of non-magnetic materials—paramagnetic materials (titanium, aluminum)—thereby identifying them (based on the spectrum of mechanical resonant oscillations) and their range—based on time—i.e., the passage of underwater acoustic shock waves. Furthermore, due to the deep penetration characteristics of pulsed magnetic fields and mechanical shock fields through the metal shell, it is possible to detect stationary objects hidden beneath layers of silt and soil.

[0153] In this case, the magnetic frame antenna is used (alternatingly) in two modes: first, the impact magnetization mode of the object, and second, the induction mode with parametric modulation recording.

[0154] In the first case, a strong magnetic field is generated to magnetize the object being detected; in the second case, the information capture parameter magnetic field is used.

[0155] The present invention (method and apparatus) can be characterized by any combination of at least one of the following features:

[0156] • Search for the remanent magnetization of the object

[0157] • Parameter modulation of reflected harmonic magnetic field

[0158] • Penetration characteristics of pulsed magnetic fields through metal casings

[0159] • Penetration characteristics of electro-hydraulic shock through metal casing

[0160] • Search for the local micro-displacement of the object.

[0161] Simultaneously, a dedicated electro-hydraulic unit (EHU) is used as a powerful underwater electrical energy source, with the following load:

[0162] 1-Radiating magnetic frame antenna with vibration-resistant structure in the case of generating impact pulse magnetic field (operating in the object magnetization mode);

[0163] 2- In the case of generating harmonic magnetic fields - a radiating magnetic loop antenna that forms an induction channel (with information influenced by parameter modulation recording);

[0164] 3- An electro-hydraulic discharger that generates overpressure pulses (underwater acoustic shock waves) in response to mechanical impacts. Detailed Implementation

[0165] This invention can be advantageously implemented through a method for detecting search objects (such as underwater robots and drones) using a search device suitable for magnetic measurement searches of ferromagnetic objects. A powerful underwater electrical power source and a radiating magnetic loop antenna are used to generate an impulsive pulse magnetic field. This impulsive pulse magnetic field magnetizes the ferromagnetic elements of the ferromagnetic search object, causing a change (increase) in the magnetic field of the search object due to residual magnetization. This change or increase in the magnetic field of the search object is recorded by a magnetic measurement receiver.

[0166] An advantageous feature of this method is that a mechanical force impact is additionally applied in the form of a single overpressure pulse via an electro-hydraulic shock pulse (referred to as electro-hydraulic shock, electro-hydraulic impact, electro-hydraulic strike, electro-hydraulic oscillation, or physical shock), which causes changes in physical properties, such as changes in the magnetic field of the search object and / or changes in specific properties (“sudden” changes), such as malfunctions in the electronic circuitry of the search object. By applying the electro-hydraulic shock pulse, the parameters of the reflected detection signal of the search device change. Parameter effect or parameter modulation herein refers to the change in the parameters of the reflected detection signal of the search device due to exposure of the search object to the electro-hydraulic shock pulse.

[0167] In addition to the impulsive pulse magnetic field, the detection signal also includes informational effects generated by the defined harmonic magnetic field.

[0168] The influence of the harmonic magnetic field of a magnetic loop antenna on the information of the searched (metal) object (for detecting underwater robots and drones) is performed by recording the parametric modulation of the harmonic magnetic field defined by the reflection – in short: parametric effect.

[0169] A pulsed excitation magnetic field magnetizes the ferromagnetic components of an underwater robot or drone. Due to the so-called hysteresis loop in ferromagnets—a known phenomenon where some magnetic domains remain aligned after the magnetic field is removed—this results in an increase in the object's own magnetism due to remanent magnetization, which is recorded by a magnetometer receiver. In other words, the magnetic field of the object itself increases.

[0170] The effect of an additional excitation field on the search object is called parameterization; it aims to alter the properties of the search object itself (reflection, magnetism, nonlinearity, and other physical properties). In this case, the parameter field alters the properties of the search object itself, thereby increasing its magnetism, i.e., making it physically more noticeable to a magnetic force measurement receiver.

[0171] The parameter effect refers to the physical properties of the search object induced by the electro-hydraulic shock pulse, as well as the changes in both the search object and the detection signal reflected by the search object, which alter the parameters of the reflected detection signal of the search device.

[0172] The method of using, for example, low-frequency harmonic magnetic fields to detect and search for objects while simultaneously recording the reflected magnetic field is commonly referred to as the "inductive search method".

[0173] If the object being searched is simultaneously exposed to an additional excitation parameter physical field, a parametric effect may occur due to changes in the object's properties and consequently, changes in the parameters of the reflected magnetic field.

[0174] When searching for an object using a low-frequency harmonic magnetic field, the magnetic field reflected by the object contains variations due to changes in the object's signal parameters (amplitude, frequency, phase). This manifests as, for example, parametric modulation of the harmonic magnetic field or a so-called "burst," which occurs when the object is subjected to an electro-hydraulic shock.

[0175] In the proposed invention, the shock wave caused by the electro-hydraulic shock is a pulse of the parametric excitation field that acts on the search object and causes changes in the parameters of the search object. In this case, the shock wave on the detected metallic object causes short-term changes in the distances (r and h) between the search object, the magnetic frame antenna, and the receiver.

[0176] This causes at least a portion of the search object to undergo a slight spatial displacement relative to the magnetic loop antenna and the receiving device. The reflected signal from the detection field will naturally change. Its modulation differences carry information about the search object.

[0177] This results in a parameter amplitude modulation (“burst”) of the reflected harmonic magnetic field.

[0178] This parametric modulation of the reflected signal is physically caused by two factors: the change in the reflected signal pattern and the spatial micro-displacement of the search object at the moment of the magnetic field “burst” (also known as “burst”), which is caused by the pulse overpressure on the search object during the electro-hydraulic shock.

[0179] It is important to emphasize that, compared to electro-hydraulic impact pulses, underwater sonar (also simply called "sonar," "echo sounder," or described as "electrically generated underwater sound waves") uses harmonic signals with frequencies ranging from tens to hundreds of kHz, and its purpose is for the transmission and reception of information. Existing technology specifically includes sonar systems for detecting underwater objects.

[0180] In contrast, electro-hydraulic shock is equivalent to an underwater electric explosion, with parameters similar to a TNT explosion, causing shock excitation to the aquatic environment and generating a single overpressure pulse lasting tens of microseconds.

[0181] In the proposed invention, the shock wave caused by electro-hydraulic shock is a pulse of the parametric excitation field that acts on the search object and causes changes in the parameters of the search object.

[0182] The physical basis of electro-hydraulic shock is the conversion of electrical energy into mechanical energy, which is efficient and occurs without intermediate steps. The electro-hydraulic effect is a pulsed discharge in a liquid, resulting in a rapid, almost instantaneous release of energy in the discharge channel. Therefore, the pressure in the outlet channel significantly exceeds the external pressure, causing the channel to expand rapidly, which leads to the generation of a shock wave.

[0183] In the proposed invention, the shock wave caused by electro-hydraulic shock is a pulse of parametric excitation field that acts on the search object and causes changes in the parameters of the search object: reflection, nonlinearity, magnetism, and other properties.

[0184] Simultaneously, low-frequency harmonic magnetic fields are used to detect and search for objects. The magnetic field reflected by the object "contains" "traces" of changes in the object's signal parameters (amplitude, frequency, phase), i.e., when the object is subjected to electro-hydraulic shock, the object currently exhibits parameter modulation or "burst" of the harmonic magnetic field.

[0185] Advantageously, in performing this method, the deep-penetrating properties of pulsed magnetic fields and mechanical shock physical fields (including shock pulsed magnetic fields and electro-hydraulic shock pulses) can be utilized to penetrate the metal casing of the object being detected. Exposing the search object to magnetic fields and mechanical shock physical fields causes malfunctions in local electronic circuits within the search object. The corresponding changes in operating modes and the level variations of reflected signals in characteristic "burst" forms are recorded as additional informational features.

[0186] The apparatus suitable for performing the above method and shown in whole or in part in Figure 1 for detecting search objects (such as underwater robots and drones) is advantageously equipped with a magnetic measurement receiver 8 and a unit for recording the measurement results of magnetic field distortion from the search object 6. The apparatus is characterized in that it comprises:

[0187] -Electrical energy source 1,

[0188] -Magnetic shock pulse field generator 2

[0189] - Harmonic signal generator 3

[0190] -Pulse mechanical force impact source 4

[0191] -Radiating magnetic frame antenna 5.

[0192] - Receiver 7 for reflecting magnetic fields,

[0193] -Object distance meter 9, and

[0194] - Control module 10.

[0195] Figure 1 shows a block diagram of the apparatus for implementing the proposed method for detecting underwater robots and drones.

[0196] In the search mode, the generator 2 transmits an impact pulse magnetic field to the water environment via the magnetic loop antenna 5, magnetizing the search object 6. Due to the residual magnetization, the Earth's magnetic field is distorted, but the detection range of the magnetic force measurement receiver 8 for the search object is increased (parametric magnetization mode).

[0197] Harmonic signal generator 3 periodically transmits low-frequency harmonic magnetic fields into the aquatic environment via magnetic loop antenna 5. Simultaneously, pulsed mechanical force source 4 generates underwater acoustic shock waves, which act on the target object and cause parameter modulation of the reflected harmonic magnetic field. When entering the detection range, the target object 6 reflects the low-frequency magnetic field, which is recorded by receiver 7 (search mode). Furthermore, due to the high penetrating power of the pulsed magnetic field and mechanical shock field through the main body shell, faults in the electronic circuitry of the detected object are captured as additional information indicators.

[0198] The pulsed magnetic field shock generator 2 and the pulsed mechanical force shock generator 4 are operated via a dedicated electro-hydraulic unit (EHU) 1. For pulsed parameter shock magnetization, the output of EHU 1 is connected to the transmitter. This is a magnetic frame antenna with a large diameter (several meters) and strong mechanical strength.

[0199] Under the influence of force, the output of EHU 1 is switched by the control module 10 to different loads (electrode system), thereby generating electro-hydraulic shock pulses, also known as underwater acoustic shock waves, etc.

[0200] The control module 10 ensures the switching of the operating modes of EHU 1 and generators 2-4; supplies power to all modules of the equipment; controls the operation of the harmonic magnetic field receiver 7, the magnetic force measurement receiver 8, and the object distance meter 9; performs data processing and storage; and displays information.

[0201] Figure 3 shows a more detailed view of Figure 1.

[0202] Information source

[0203] 1. Bukaty VM Field Acoustics and Fish Detection, M.: "World", 2003, pp. 457-488;

[0204] 2. Goncharsky VN et al. Technical basis of airborne electrical exploration. Scientific ideas. Kiev, 1969, 380 pages.

[0205] 3. Shcherbakov, Detection of Hidden Objects in GN. M.: “Arbat-Infom”, 2004, pp. 28-33.

[0206] 4. Shapiro DN Electromagnetic Shielding Theory. "Energy", Leningrad, 1975, p. 112.

[0207] 5. Apollonsky SM Electromagnetic Shielding Enclosure Calculation. "Energoizdat", Leningrad, 1982, p. 144.

[0208] 6. Goncharsky VN et al. Fundamentals of Airborne Electrical Exploration Technology. Scientific Ideas. Kiev, 1969, 380 pages.

[0209] 7. Bukaty VM, Field Acoustics and Fish Detection. "World". Moscow, 2003, 496 pages.

[0210] 8. Ricketts LW et al. Electromagnetic Pulse and Protection Methods. English translation. Edited by Ukhina NA, M., Atomic Press, 1979, 328 pages.

[0211] 9. On the impact of nuclear explosion conditions on the operation of military electronic systems. Foreign Radio Electronics. M. 1985 edition. 9(1033), pp. 10–13.

[0212] 10. Kolensky LL, Medvedev Yu.A. Pulsed electromagnetic waves penetrate into the cavity of a conductive cylinder. Journal of University. Radio Physics Series, 1969, Vol. XII, No. 4, pp. 588–592.

[0213] 11. Myrova LO et al. Ensuring the resistance of communication equipment to ionization and electromagnetic radiation. M. Radio and Communications, 1988, p. 296.

[0214] 12. Ozeretskovsky, Effects of OI Explosions on Underwater Objects. M.FSUE “TsNIIHM”

[0215] 2007, page 262.

[0216] 13. Cole R. Underwater Explosion. M.IL, 1950.

[0217] 14. Zamyshlyaev BV et al. Dynamic loads during underwater explosions. L. Shipbuilding, 1967.

Claims

1. A method for detecting underwater robots and unmanned aerial vehicles, the method using a search device suitable for magnetic force measurement searches of ferromagnetic objects, wherein, An impact pulse magnetic field is generated, which magnetizes the ferromagnetic elements of the search object, causing a change (increase) in the magnetic field of the search object due to residual magnetization. This change is recorded by a magnetic force measurement receiver. The feature is that... Additionally, a mechanical impact is applied in the form of a single overpressure pulse via electro-hydraulic shock pulses. This impact alters the physical properties and characteristics of the search object, thereby changing the parameters of the reflected detection signal of the search equipment; this is known as the parameter effect. In addition to the impulsive pulse magnetic field, the detection signal also includes harmonic magnetic fields. The detection of underwater robots and drones is performed by recording the parametric effects of reflected harmonic magnetic fields.

2. The method according to claim 1, Its features are, By utilizing the deep penetration characteristics of pulsed magnetic fields and mechanical impact physical fields, the signal penetrates the metal shell of the object being tested. This causes local electronic circuits inside the object to malfunction, and the operating mode and the level changes of the reflected signal in the form of characteristic "bursts" are recorded as additional information features.

3. An apparatus for detecting a search object, such as an underwater robot and a drone, comprising a magnetic force measurement receiver (8) and a unit for recording measurements of magnetic field distortion from the remanent magnetization of the search object (6). Its features are, The device includes: The device includes an electric energy source (1), a magnetic shock pulse field generator (2), a harmonic signal generator (3), a pulse mechanical force shock source (4), a radiating magnetic frame antenna (5), a receiver (7) configured to receive paramagnetically modulated reflected harmonic magnetic fields, an object distance meter (9), and a control module (10).

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