Detection method for underwater robots and drones, and suitable device for implementation thereof.

Abstract

This invention relates to the field of detecting ferromagnetic underwater objects and other artificially created objects. The technical outcome 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 hybrid structures. The proposed detection method is based on using a radiating magnetic loop antenna in two operating modes: a first-parametric magnetization mode and a second-parametric modulation induction mode, and a channel of mechanical force collision by electrohydraulic shock. At the same time, due to the high penetration capability of the pulsed magnetic field and mechanical shock physical field, malfunctions in the electronic circuits of the detected object are captured as additional information features through the main shell.

Description

[Technical Field]

[0001] The present invention relates to a detection method for searched objects, and to a device for detecting searched objects, such as an underwater robot and a drone.

[0002] This invention relates to the detection of ferromagnetic underwater objects and other artificially created objects, particularly to the detection of underwater robots and drones that are prevalent in the modern world.

[0003] The most challenging problem is detecting stationary objects. These are so-called underwater "bookmarks"—robot capsules—that are deployed underwater for weeks, months, or even years, activated by signals, and then, after surfacing below or above the water's surface, perform and activate some function.

[0004] The detection of such underwater robotic capsules is a matter of utmost urgency to ensure the security of seaports, river ports, vessels, and coastal infrastructure. [Background technology]

[0005] Underwater acoustic methods are known for detecting objects in underwater environments. These methods are based on recording underwater acoustic signals reflected from underwater objects.[1]

[0006] A drawback of this method is that it is practically impossible to detect stationary underwater objects, especially when there is background interference due to the irregularities of the seabed.

[0007] Induction methods are known for detecting ferromagnetic (and nonferromagnetic) metallic objects.[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 invention closest to the claimed invention is a magnetic measurement and detection method that enables the detection of ferromagnetic objects in a variety of environments, including underwater.[3]

[0010] Magnetic measurement methods are known to enable the recording of spatial distortions of the Earth's magnetic field created by ferromagnetic search objects. It is possible to detect objects whose structure contains ferromagnetic elements (body, mechanical parts, and electrical components) in any natural environment, namely seawater and freshwater, very deep clay and sandy soils, and ice. The strength of the Earth's magnetic field is 0.34 oorsted at the magnetic equator, 0.66 oorsted at the magnetic poles, and 0.57 oorsted at the central latitude (approximately 40 A / m in the SI system).

[0011] In this field, magnetometers are the most commonly used. A device is created that uses two magnetic receivers to measure the difference in magnetic flux density at two points in space. In this case, the device is called a magnetic gradient meter.

[0012] The drawback of this method is its insufficient detection range, which is limited to localized ferromagnetic objects of 6-8 meters or less. The characteristic dimensions of such objects are typically a few tenths of a meter to several meters.

[0013] U.S. Patent No. 6,335,624 discloses the detection of conductive objects hidden near the surface within the seabed, such as mineral deposits lying near the coast.

[0014] DE102016112524A1 discloses a method for electromagnetic detection and surface surveying to locate metallic foreign objects hidden beneath the seabed surface, particularly for searching for unexploded ordnance.

[0015] U.S. Patent No. 5,598,152 discloses the detection of submerged objects by generating electric or magnetic fields and measuring their deviations and changes. Magnetic objects cause changes due to the magnetization of the magnetic object based on the emitted electric or magnetic field. Non-metallic objects submerged in seawater cause deviations in the generated electric or magnetic field by creating "holes" in the conductivity pattern of the seawater.

[0016] AU632320B2 discloses the detection of objects submerged in brine or saltwater by generating magnetic fields and measuring their deviations and changes. The generation of the magnetic field is done as a pulse having a sharp transition from one essentially constant voltage to at least one other essentially constant voltage.

[0017] RU2444765C2 discloses a method for detecting submerged objects by using a pulsed magnetic field to generate mechanical vibrations of the object being searched for, and then detecting those vibrations acoustically underwater.

[0018] U.S. Patent No. 6,215,734 discloses an electrohydraulic projector for generating sound and pressure waves. It includes an energy source, such as a capacitor, arranged within a radius of approximately 1 meter of the electrode arrangement configuration. A larger projector can be formed by arranging multiple projectors, and an even larger projector can be formed by arranging them side by side. [Overview of the Initiative]

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

[0020] This objective is achieved through the features of the independent claim. A favorable development begins with the dependent claim.

[0021] The detection of ferromagnetic underwater objects is achieved by the additional introduction of an impact-pulse magnetic field channel. This channel magnetizes the ferromagnetic elements of the detected object, while the change (increase) in the object's magnetic field is caused by residual magnetization, which is recorded by a magnetic measurement receiver.

[0022] The detection of ferromagnetic (and non-ferromagnetic) underwater objects is based on an additional pulsed mechanical force impact by electro-hydraulic shock and an informational influence on the detected object by a harmonic magnetic field from a magnetic frame antenna with registration of parametric modulation ("burst") of the reflected harmonic magnetic field.

[0023] The mechanical force impact of the electro-hydraulic shock on the detected metal object causes short-term (pulse) changes in the distances (r and h) between the search object, the magnetic loop antenna, and the receiver.

[0024] This results in parametric amplitude modulation ("burst") of the reflected signal of the harmonic magnetic field under investigation, which is registered by the magnetic measurement receiver as an additional information feature.

[0025] This improves the search performance.

[0026] Most of the outer shells (bodies) of underwater robots and drones are made of ferromagnetic materials. However, the possibility of manufacturing them from other materials that do not exhibit magnetic properties, such as titanium, bronze, brass, etc., must be considered. Underwater acoustic shock waves generate pulsed overpressure and penetrate the ferromagnetic or non-ferromagnetic outer shells of the detected objects.

[0027] Inside the housing shell, there are movable and stationary parts of the object (robot or drone), namely electric motors, batteries, electromechanical drives of manipulators, mechanical elements of the execution module, and devices of the control system. Their positions within the housing shell are connected by fastening elements, pulleys, hinges, and springs.

[0028] The overpressure pulses of an electro-hydraulic shock penetrate the shell, causing a resonant "splash" and the object to "vibrate."

[0029] The pulsed magnetic field and mechanical shock field have the characteristic of penetrating deeply into the main shell of the detected object, partially disrupting the function of the electronic circuits inside the object. This alters their operating modes and changes the level of the reflected signal in a characteristic "burst" form.

[0030] Therefore, even partial damage to the electronic circuits (electromechanical elements) of underwater robots and drones can reveal additional information about the object.

[0031] A key objective of increasing the maximum detection depth is to create conditions in which the searched object distorts the Earth's magnetic field more strongly. This is achieved by methods of remote parametric magnetization, which is a special case of parametric location in semiconductor media.

[0032] In the first approximation, locally detected objects can be replaced by solid ferromagnetic spheres. A ferromagnetic sphere in the Earth's uniform magnetic field behaves like a magnetic dipole with a moment determined by the following equation.

[0033] (1) TIFF2026525144000002.tif9170 However, Rsp - Radius of the ferromagnetic sphere (object being searched for) Permeability of μ1-spherical material μ0 - Permeability of the surrounding natural environment (water, soil) H0 is the Earth's constant magnetic field.

[0034] In practice, when searching for localized ferromagnetic objects, the gradient of the anomalous magnetic field is usually measured, rather than its absolute value.

[0035] The maximum detection range of a ferromagnetic sphere using a magnetic gradient meter can be estimated using the following formula.

[0036] (2) TIFF2026525144000003.tif17170 where min is the magnetic field sensitivity T / m of the gradient meter (distortion of the magnetic field in space per unit length, where B is the magnetic flux density). [Modes for carrying out the invention]

[0037] The sensitivity of modern portable magnetic gradient meters is 10 -7 ~10 -8 It is T / m. If the radius of the ferromagnetic sphere is 0.3 to 0.5 m, then 10 -8 The detection range at T / m sensitivity is 6-8m.

[0038] The majority of the bodies of underwater robots located within the water column are made of polycrystalline ferromagnetic materials, mainly steel.

[0039] Depending on the chemical composition of the alloy and the geometric shape of the object, various structural and phase changes occur in its physical and mechanical properties during magnetization (Figure 2). These changes generally result in a qualitative increase in the efficiency of devices for detecting search objects, such as underwater robots and drones, including search equipment, regardless of the principles of their structure.

[0040] Therefore, phase transitions generally result in an increase in the intrinsic magnetic field due to a stronger alignment of the magnetic moments of the magnetic domains.

[0041] The detection range of a magnetized ferromagnetic sphere can be estimated using the following formula.

[0042] (3) TIFF2026525144000004.tif17170 However, K dem - The demagnetization coefficient is 0.33 for a sphere. H ext - The amplitude of the external magnetization is A / m.

[0043] From equation (3), it follows that magnetizing a sphere with a pulsed magnetic field having an amplitude of 1 kA / m increases the detection range by approximately 80%.

[0044] It should be noted that the duration of the magnetization pulse can be very short. For wall thicknesses of 1 to 10 mm in the searched object, it is only one-tenth to one-hundredth of a second. This is determined by the thickness of the "surface" layer for steel, based on shielding theory [4, 5]. The short duration of the pulse, accompanied by long pauses (several seconds to tens of seconds), ensures low power consumption in the technical implementation of this method.

[0045] Field experiments were conducted to test the most complex elements of the proposed method.

[0046] The detection range of ferromagnetic objects in freshwater and seawater is the same as in soil. Furthermore, in the latter case, soil moisture does not affect the detection range. When searching underwater, a magnetometer was mounted on a non-magnetic floating body (rubber boat). The floating body did not contain any ferromagnetic elements (brackets, nails, staples, etc.) in its structure.

[0047] The experimental setup generated pulsed magnetic fields with an amplitude of 500–700 A / m and a duration of 20 ms at the location of the searched object. The searched object was as follows: • Steel balls with diameters of 5 cm and 10 cm (reference objects for search) • A steel pipe with a diameter of 10 cm and a length of 30 cm (model for an underwater robot)

[0048] up to 10 -7 A portable magnetometer, MBI-2, with a sensitivity of T / m, was used as a search instrument.

[0049] Furthermore, the measurements were taken in freshwater in a pond with a depth of 2.5m (ε=80, n=10 -2 The test was conducted in S / m. The detection range of the object was the same as in air. The MBI-2 magnetometer was placed on a rubber boat.

[0050] A ferromagnetic object exposed to remote magnetization at Hext ≈ 500~700 A / m was detected at a distance 1.5 to 2 times higher than the limit of the MBI-2 magnetometer.

[0051] As described above, the present invention proposes a method for remote parametric magnetization of a search object to increase the detection range of ferromagnetic objects using magnetic measurement methods. However, this method only detects ferromagnetic objects.

[0052] The novel aspect of this invention (the method described in claim 2) is that it increases the detection range not only for ferromagnetic objects in water but also for metallic objects being searched for. It also becomes possible to perform recognition and determine the recognition range.

[0053] The claimed method further comprises two channels: a first channel of pulsed mechanical impact by electrohydraulic shock, and a second channel of informational influence on the object under detection by a harmonic magnetic field from a magnetic loop antenna, accompanied by registration of parametric modulation ("splash") of the reflected harmonic magnetic field.

[0054] The object being searched is irradiated with a low-frequency magnetic field for exploration, and the magnetic field reflected from the object's surface is recorded. Furthermore, pulsed mechanical force impacts are induced from an electro-hydraulic impact device (EHU).

[0055] The searched object has a more complex structure, and consequently, the reflection diagram of the secondary magnetic field from the real object also has a complex needle-like shape. Since the phase in the reflected harmonic magnetic field also changes, this enhances the effect of parametric modulation of the signal amplitude during back reflection. Therefore, when using a phase-sensitive receiver, the effect of parametric modulation is significantly enhanced.

[0056] Taking the above into consideration, the secondary (reflected) magnetic field of the object being searched is determined by the following equation.

[0057] (4) TIFF2026525144000005.tif17170 However, M is the magnetic moment of the radiating frame antenna. 0 = 4π·10 -7 H / m RSF is the radius of the object being searched (sphere), in meters. h is the distance, m, between the search object and the magnetic loop antenna. r is the distance, m, between the object being searched for and the receiver of the reflected magnetic field. D is a function that describes the anomalous low-frequency magnetic field on the surface of an object.[6]

[0058] Since the distance to the detected object is not large and the frequencies used are lower (hundreds of Hz to several kHz), the loss of harmonic LF magnetic fields in seawater (ε=80, n=4S / m) is minimal.

[0059] Under the influence of underwater acoustic shocks from the EHU equipment, there are short-term (pulse) changes in the distance (r and h) between the searched object and the magnetic frame antenna and receiver. This results in parametric amplitude modulation ("bursts") of the reflected signal. Simultaneously, characteristic resonant vibrations also occur. Each object type has its own vibration spectrum, making it possible to recognize the object type. Furthermore, optimal filtering of the received signal is possible, which increases the sensitivity of the receiver and therefore the detection range.

[0060] The distance to the object can be estimated by measuring the travel time of the underwater acoustic impact from the EHU facility to the object being searched for [7]. In this case, the impact velocity in water is known to be stable at 1485 m / s.

[0061] Stationary robots—"bookmarks" in sleep mode—can be hidden within layers of silt and seabed sediment, against the backdrop of the seabed topography, which has been shown to make their detection extremely difficult. Mechanical vibrations in the form of underwater acoustic waves passing through these layers result in significant losses.

[0062] The claimed invention (the method described in claim 3) proposes using a magnetic field (which propagates equally through both soil and seawater) and the deep-penetrating properties of shock wave forces as a mechanical effect.

[0063] The pulsed magnetic field and mechanical shock field have the characteristic of penetrating deeply into the main shell of the object to be detected, causing partial malfunction of the electronic circuits inside the object, which alters the reflected signal in the form of a characteristic "burst." Therefore, additional information indicators appear in relation to even partial damage to the electronic circuits of underwater robots and drones. The required parameters of the pulsed magnetic field are listed below.

[0064] In the first approximation, these local search objects can be represented as hollow spheres or elongated ellipsoids with electronic elements inside. Typical radio circuit malfunctions caused by induced voltages are known to begin to be detectable at pulsed magnetic field strengths exceeding 100 A / m [8, 9]. The amplitude and shape of the voltages induced in the circuit are determined primarily by the following factors: • Magnetic field strength, rise and fall times • Geometric dimensions of the circuit outline • Name of component • Interalignment of circuits and magnetic field vectors • Electrical modes (supply voltage, sensitivity to polarity reversal of input signal) • Structural arrangement of the circuit mounted on the device's metal housing

[0065] The penetration of pulsed magnetic fields into a shield structure occurs through two mechanisms: magnetic field diffusion through the walls due to the walls' non-ideal conductivity, and magnetic field penetration through holes.

[0066] As is known, a pulse signal can be expressed as a sum of harmonic components. In a severe environment, a boundary problem is imposed to determine the penetration of the harmonic electromagnetic field penetrating inside a solid conductive shield. That is, Maxwell's equations are considered in three regions (outside, within the wall of the shield, and inside). In the case of the simplest configuration of the shield (case), an analytical expression for the transfer function, that is, the ratio of the magnetic field penetrating the shield to the external magnetic field, can be obtained

[10] . From this transfer function, the impulse response of the screen can be determined by inverse Fourier transform. However, even for the simplest screen, the frequency dependence of its transfer function is still very complex, and it is not possible to obtain an expression for the impulse response of the screen in an analytical form having a finite number of terms

[11] .

[0067] If there is a concise solution to the problem of a pulsed magnetic field penetrating the metal shell of a screen, it is possible to use the average frequency of the video pulse spectrum. This makes it possible to apply a considered insight into the theory of the propagation of harmonic electromagnetic fields through a conductive medium.

[0068] The propagation process of the harmonic magnetic field in a conductor is explained by the following equation. (5) TIFF2026525144000006.tif11170(6) TIFF2026525144000007.tif121-70h - The penetration depth of the magnetic field into the metal, in m μ0 = 4π·10 -7 - Permeability in vacuum, H / m

[0069] The average frequency of the video pulse spectrum is (7) TIFF2026525144000008.tif9170 where ΔT is the pulse duration of the magnetic field.

[0070] Next, (8) TIFF2026525144000009.tif7170

[0071] The damping coefficient Ka is the ratio of the amplitude Hf of the magnetic field at the thickness of the conductor (metal) to the amplitude H1 of this magnetic field at its surface (before penetration into the metal).

[0072] Currently, the housings (shells) of small underwater devices (robots and drones) are often made of titanium instead of steel. This is due to two factors. Titanium is stronger than steel. • Lack of magnetic demasking properties makes detection more difficult.

[0073] The wall thickness of the shell is typically a few millimeters, or 1 to 10 mm.

[0074] Graph 1 shows the dependence of the attenuation coefficient of pulsed magnetic fields on the duration of these pulses. Shortening the duration increases the average frequency of the spectrum, which leads to increased magnetic field attenuation with respect to the thickness of the metal (titanium).

[0075] The properties of titanium in the calculations are: • Electrical conductivity γ = 2·10 7 S / m TIFF2026525144000010.tif69170 Graph 1 Dependence of the attenuation coefficient of a pulsed magnetic field in a metal on pulse duration. Housing material (screen) - Titanium • Relative permeability is equal to 1 (paramagnetic).

[0076] Graph 1 shows that for magnetic field pulse durations exceeding 1 ms and titanium shell thicknesses of 1 mm to 10 mm, losses are minimal when the magnetic field penetrates the screen. This allows for the use of pulsed magnetic fields in designs to deactivate internal modules of various underwater devices, including electronic components.

[0077] By incorporating an electro-hydraulic equipment (EHU) or device that generates electro-hydraulic shock or electro-hydraulic shock pulses, it is possible to generate pulsed magnetic field strengths of 100 A / m or more. However, in this case, the high-voltage capacitor battery is not connected to the spark gap but to a frame antenna with a large diameter (several meters).

[0078] The pulse-like mechanical impacts caused by electro-hydraulic shock also possess high penetration capabilities, allowing them to pass through both ferromagnetic shells and the walls of the object's body, which may be made of other materials.

[0079] It is known that the outer shells (bodies) of most underwater robots and drones are made of ferromagnetic materials. However, the possibility of manufacturing them from other materials that do not exhibit magnetic properties, such as titanium, bronze, and brass, must be considered.

[0080] Underwater acoustic shock waves generate pulsed overpressures that penetrate the non-ferromagnetic outer shell of the object to be detected.

[0081] The movable and stationary components of the object (robot or drone), namely electric motors, batteries, electromechanical drives of manipulators, mechanical elements of control modules, and control system devices, are housed within the main body shell. Their positions within the main body shell are connected by fastening elements, pulleys, hinges, and springs.

[0082] The overpressure pulse from the electro-hydraulic shock penetrates the inside of the shell, causing a resonant "splash" and the object to "vibrate."

[0083] The electronics of underwater robots and drones can be disabled by shock waves [12-14]. Such strikes are possible using electro-hydraulic shocks. A characteristic of this process is that the conversion of electrical energy to mechanical energy occurs without an intermediate link. The pressure in the discharge channel between high-voltage electrodes (typically a few centimeters to tens of centimeters) can reach tens of thousands of atmospheres. The voltage values ​​are typically in the range of 10kV to 100kV. In this case, the duration of the discharge itself is typically a few microseconds to tens of microseconds. Such durations are common for the explosion of small charges of typical TNT (tens of grams to several kilograms).

[0084] The formula for estimating the pressure at the shock wave front in water generated by an electro-hydraulic unit (EHU) has the following form: (9) TIFF2026525144000011.tif7170(10) TIFF2026525144000012.tif8170 However, C is the capacitance of the capacitor bank, F. The voltage across the U-capacitor is V. η is the conversion coefficient for the electrical energy of a discharge to the mechanical energy of a shock wave (0 < η < 0.35).

[0085] Graph 2 shows the dependence of pressure at the shock wavefront generated by the EHU facility on distance (η=0.25). TIFF2026525144000013.tif72170 Graph 2: Dependence of pressure at the wavefront generated by the EHU equipment on distance.

[0086] There are two possible scenarios for the malfunction of an underwater object. • Destruction of metal housings (titanium, steel) • Deactivation of various electronic devices within the outer casing

[0087] In the first case, the pulse pressure should be several hundred atm, and in the second case, it should be several tens of atm (approximately).

[0088] 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 manufactured as an integral part of the outer shell are used.

[0089] A potential malfunction in a vulnerable underwater acoustic receiving sensor is when the operation of the input-sensitive amplifier is interrupted by the large pulse voltage generated by the piezoelectric sensor.

[0090] However, if a regular object—a robotic capsule—is exposed to electrohydraulic impulses and pulsed magnetic fields to deactivate its underwater acoustic and magnetic orientation and target sensors, it must be clear that in sleep mode, the sensitive sensors are inactive, the electronic circuits are switched off, and there are protective devices for the environmental contact sensors and electronics. In this regard, malfunctions of the underwater acoustic and magnetic orientation sensors of the targeting robotic capsule are unlikely.

[0091] Therefore, the crucial point for practical purposes is that the underwater acoustic shock wave penetrates the metal shell of the main body.

[0092] In practical terms, a metal plate submerged in water can be considered. It is known that the pressure in an incident wave changes exponentially. With some simplification (assuming the shock wave propagates along the outer shell and structural elements), the pressure behind the metal plate can be determined using the following equation [12-14]. (11) TIFF2026525144000014.tif11170(12) TIFF2026525144000015.tif11170(13) TIFF2026525144000016.tif11170 However, density of P-plate material δ-plate thickness y - complex parametric coefficients p0 is the density of water. c0 Speed ​​of sound in still water TIFF2026525144000017.tif9170 represents a shortened distance.

[0093] Graph 3 shows that the protective properties of the metal plate when placed in water are minimal. The maximum pressure behind the barrier decreases by less than 20%. TIFF2026525144000018.tif74170 Graph 3 Pressure in shock wave passing behind a metal plate as a function of time

[0094] Therefore, almost all of the energy of the mechanical force generated by the electro-hydraulic shock is exerted on the shell and internal structure of the object to be detected.

[0095] This can be concluded as follows:

[0096] The above enables the detection of both ferromagnetic objects and objects whose shells are made of non-magnetic materials—paramagnetic materials (titanium, aluminum)—and their passage (according to the spectrum of mechanical resonant vibrations), as well as their range—over time—i.e., the passage of underwater acoustic shock waves. Furthermore, the deep-penetrating properties of pulsed magnetic fields and mechanical shock fields penetrating the metal shell of the housing make it possible to detect stationary objects hidden beneath layers of sludge and soil.

[0097] In this case, the magnetic frame antenna is used (alternatingly) in two modes: firstly, in the mode of impulse magnetization of an object, and secondly, in the mode of induction with registration of parametric modulation.

[0098] In the first case, a force magnetic field is generated to magnetize the detected object, and in the second case, an information acquisition parametric magnetic field is generated.

[0099] The present invention (method and apparatus) can be characterized by at least one of the following features in any combination. - Residual magnetization of the object being searched - Parametric modulation of reflected harmonic magnetic fields - Penetration characteristics of pulsed magnetic fields through a metal shell - Penetration characteristics of electrohydraulic collisions through a metal shell - Partial minute displacement of the object being searched for

[0100] At the same time, a dedicated electro-hydraulic unit (EHU) is used as a powerful underwater source of electrical energy, and its load includes the following: 1. When generating shock / pulsed magnetic fields - A vibration-resistant magnetic frame antenna (operating in object magnetization mode) 2. When generating harmonic magnetic fields - Radiation magnetic loop antenna that forms an induction channel (informational effects with registration of parametric modulation) 3. Electro-hydraulic discharger that generates overpressure pulses (underwater acoustic shock waves) for mechanical force collisions.

[0101] Implementation of the present invention The present invention has the advantage of being realized through a method for detecting search objects, such as underwater robots and drones, using search equipment suitable for magnetic measurement and search of ferromagnetic objects. A powerful underwater electrical energy source and a radiating magnetic loop antenna are used to generate a shock-pulsed magnetic field. The shock-pulsed magnetic field magnetizes the ferromagnetic elements of the ferromagnetic search object, changing (increasing) the magnetic field of the search object by remanent magnetization. This change or increase in the magnetic field of the search object is recorded by a magnetic measurement receiver.

[0102] The method is further advantageous in that the mechanical force collision is induced in the form of a single overpressure pulse by an electro-hydraulic impact pulse, which is also referred to as electro-hydraulic impact, electro-hydraulic impact, electro-hydraulic strike, electro-hydraulic shock, or physical shock, and the collision results in special characteristics ("bursts") such as altered physical properties of the magnetic field of the object being searched and / or malfunction of the electronic circuits of the object being searched. By inducing an electro-hydraulic impact pulse, the parameters of the reflected search signal of the search instrument are changed. Hereinafter, parametric effect or parametric modulation refers to the change in the parameters of the reflected search signal of the search instrument as a result of exposing the object being searched to an electro-hydraulic impact pulse.

[0103] The search signal includes informational influences from defined harmonic magnetic fields, in addition to the impact and pulsed magnetic fields.

[0104] For detecting underwater robots and drones, the informational influence of the harmonic magnetic field of a magnetic loop antenna on detected (metallic) search objects is carried out in conjunction with the registration of the parametric modulation—short for parametric effect—of the reflected, defined harmonic magnetic field.

[0105] A pulsed excitation magnetic field magnetizes the ferromagnetic elements of an underwater robot or drone. Within the ferromagnetic material, the presence of a so-called hysteresis loop—a known phenomenon where some magnetic domains remain aligned after the magnetic field is removed—results in an increase in its own magnetic properties due to remanent magnetization, which is recorded by a magnetic measurement receiver. In other words, the magnetic field of the object being searched increases.

[0106] The collision of an additional excitation magnetic field with a search object is called parametric, and its purpose is to alter the properties of the search object itself (reflection properties, magnetic properties, nonlinear properties, and other physical properties). In this case, the parametric magnetic field alters the properties of the search object itself, thereby increasing its magnetic properties, i.e., making it more physically detectable by a magnetic measurement receiver.

[0107] Parametric effects refer to the altered physical properties of both the search object and the search signal reflected by the search object, which are induced by electrohydraulic shock pulses and alter the parameters of the reflected search signal from the search instrument.

[0108] For example, searching for an object using a low-frequency harmonic magnetic field while simultaneously recording the reflected magnetic field is generally referred to as the "guided search method."

[0109] If the object being searched is simultaneously exposed to an additional excitation parametric physical field, parametric effects can arise from the properties of the object itself and, consequently, from changes in the parameters of the reflected magnetic field.

[0110] When searching for an object using low-frequency harmonic magnetic fields, the magnetic field reflected by the object includes changes due to the modified parameters (amplitude, frequency, phase) of the object's signal, i.e., when the object is subjected to electrohydraulic shock, it exhibits, for example, parametric modulation or a so-called "burst" of the harmonic magnetic field.

[0111] The shock wave induced by the electro-hydraulic shock in the proposed invention is a pulse of parametrically excited magnetic field acting on the object being searched, causing a change in its parameters. In this case, the shock wave on the detected metallic object results in a short-term change in the distance (r and h) between the object being searched and the magnetic frame antenna and receiver.

[0112] This results in a small spatial displacement of at least a portion of the searched object relative to the magnetic loop antenna and receiving device. The reflected signal of the search magnetic field will naturally change. This modulation difference carries information about the searched object.

[0113] This results in parametric amplitude modulation ("bursts") of the reflected harmonic magnetic field.

[0114] This parametric modulation of the reflected signal is physically caused by two factors: a change in the directional pattern of the reflected signal due to pulsed overpressure on the search object during electrohydraulic impact, and a small spatial displacement of the search object at the point of a magnetic field "burst," also known as an "outbreak."

[0115] At this point, it is important to emphasize that underwater sonar, also abbreviated as "sonar" or "acoustic depth sounder," or described as "electrodynamically generated underwater sound waves," in contrast to electro-hydraulic shock pulses, uses harmonic signals with frequencies of tens to hundreds of kHz, and its use is useful for transmitting and receiving information. Current technology includes sonar systems, in particular, for detecting underwater objects.

[0116] In contrast, electro-hydraulic shock is equivalent to an electrical explosion in water with parameters similar to a TNT explosion, which causes shock excitation in a water environment, i.e., a single overpressure pulse with a duration of tens of microseconds.

[0117] The shock wave generated by the electrohydraulic shock in the proposed invention is a pulse of parametric excitation magnetic field that acts on the object being searched and causes a change in its parameters.

[0118] The physical basis of electro-hydraulic shock is the conversion of electrical energy into mechanical energy with high efficiency and without intermediate links. Electro-hydraulic action is a pulsed discharge in a liquid, in which case a rapid, almost instantaneous release of energy occurs within the discharge channel. As a result, the pressure within the outlet channel significantly exceeds the external pressure, causing the channel to expand rapidly, which leads to the generation of a shock wave.

[0119] The shock wave generated by the electrohydraulic shock in the proposed invention is a pulse of parametrically excited magnetic field acting on the object being searched, causing changes in its parameters, namely its reflective properties, nonlinear properties, magnetic properties, and other properties.

[0120] Simultaneously, the searched object is explored using low-frequency harmonic magnetic fields. The magnetic field reflected by the object "contains traces" of the altered parameters (amplitude, frequency, phase) of the searched object's signal, i.e., currently indicating the parametric modulation or "burst" of the harmonic magnetic field when the object is subjected to electrohydraulic shock.

[0121] Advantageously, when performing this method, the characteristic of pulsed magnetic fields and mechanical shock physical fields, including shock pulsed magnetic fields and electro-hydraulic shock pulses, to penetrate deeply into the metal shell of the body of the object being detected can be utilized. Exposure of the object being searched to magnetic and mechanical shock physical fields leads to localized electronic circuit malfunctions within the object. The resulting changes in the operating mode in the form of characteristic "bursts" and the level changes of the reflected signals are recorded as additional information features.

[0122] A suitable device for implementing the above-described method and the method shown in whole or in part in Figure 1 for detecting search objects such as underwater robots and drones is advantageous to include a magnetic measurement receiver 8 and a unit for recording the results of magnetic field strain measurements from the search object 6. This device is characterized by the following: - Electrical energy source 1, - Magnetic shock pulse field generator 2, - Harmonic signal generator 3, - Source of pulsed mechanical force collisions 4, - Radiation magnetic frame antenna 5, - Receiver 7 for reflected magnetic field, - Object distance meter 9, and - Control module 10

[0123] Figure 1 shows a block diagram of a device that implements the proposed method for detecting underwater robots and drones on the seabed.

[0124] In search mode, the generator 2 emits shock pulses into the underwater environment via the magnetic loop antenna 5, which magnetizes the search object 6 and distorts the Earth's magnetic field through residual magnetization, but the magnetic measurement receiver 8 increases the detection range (parametric magnetization mode).

[0125] The harmonic signal generator 3 periodically emits low-frequency harmonic magnetic fields into the underwater environment via the magnetic loop antenna 5. Simultaneously, the pulsed mechanical force source 4 generates underwater acoustic shock waves that act on the searched object, causing parametric modulation of the reflected harmonic magnetic fields. When the searched object 6 enters the detection range, it reflects the low-frequency magnetic field, which is recorded by the receiver 7 (search mode). At the same time, the high penetrating force of the pulsed magnetic field and mechanical shock field passing through the main shell allows malfunctions in the electronic circuits of the detected object to be captured as additional information indicators.

[0126] The operation of the shock generator 2 for pulsed magnetic fields and the generator 4 for pulsed mechanical force impacts is carried out via a dedicated electro-hydraulic unit (EHU) 1. For pulsed parametric shock magnetization, the output of EHU 1 is connected to the emitter, which is a magnetic frame antenna with a large diameter (several meters) and mechanical strength.

[0127] Under the influence of force, the output of EHU1 is switched by the control module 10 to different loads (electrode systems), generating electro-hydraulic shock pulses, also known as underwater acoustic shock waves.

[0128] The control module 10 ensures the switching of operating modes of the EHU1 and generators 2-4, power supply to all modules of the equipment, and control of the operation, data processing and storage, and information display of the harmonic magnetic field receiver 7, magnetic measurement receiver 8, and object distance meter 9. [Brief explanation of the drawing]

[0129] [Figure 1] Figure 1 shows a block diagram of the device. [Figure 3]The 3rd is the 1st of the 1st century.

[0130] Source: 1.Bukaty VMField Hydroacoustics and Fish Detection,M.:“Mir”,2003,pp.457-488; 2.Goncharsky VNet al.Technical foundations of aeroelectric prospecting.Scientific thought.Kiev 1969,380 p. 3.Shcherbakov GNDetection of hidden objects.M.:“Arbat-Infom”,2004,pp.28-33; 4.Shapiro DNFoundations of Electromagnetic Shielding Theory.“Energy”,Lenin-grad,1975,112 p. 5.Apollonsky SMCalculation of electromagnetic shielding shells.“Energoizdat”,Leningrad,1982,144 p. 6.Goncharsky VNet al.Technical foundations of aeroelectric prospecting.Scientific thought.Kiev 1969,380 p. 7.Bukaty VMField hydroacoustics and fish detection.“Mir”.Moscow,2003,496 p. 8.Ricketts LWet al.Electromagnetic pulse and protection methods.Trans.from English Ed.Ukhina NA,M.,Atomizdat,1979,328 p. 9.On the influence of nuclear explosion conditions on the operation of electronic systems for military purposes.Foreign radio electronics.M.Edition 1985.9(1033),p.10-13. 10.Kolensky L.L.,Medvedev Yu.A.Penetration of pulsed electromagnetic waves into the cavity of a conducting cylinder.Izv.Universities.Ser Radiophysics 1969 T.XII,N 4 p.588-592. 11.Myrova L.O.et al.Ensuring the resistance of communication devices to ionizing and electromagnetic radiation.M.Radio and Communication,1988,p.296. 12.Ozeretskovsky O.I.The effect of an explosion on underwater objects.M.FSUE“TsNIIHM”2007,p.262. 13.Cole R.Underwater explosions.M.IL,1950. 14.Zamyshlyaev B.V.and others.Dynamic loads during an underwater explosion.L.Shipbuilding,1967

Claims

1. A method for detecting underwater robots and drones using a search device suitable for magnetic measurement and search of ferromagnetic objects, wherein an impact / pulsed magnetic field is generated to magnetize the ferromagnetic elements of the search object, the magnetic field of the search object is changed (increased) by remanent magnetization, and this is recorded by a magnetic measurement receiver, Furthermore, an electro-hydraulic impact pulse in the form of a single overpressure pulse induces a mechanical force collision, which results in altered physical properties and characteristics of the searched object, thereby changing the parameters of the reflected search signal from the search equipment, a phenomenon known as the parametric effect. The aforementioned exploration signal includes harmonic magnetic fields in addition to the shock and pulsed magnetic fields. The detection of underwater robots and drones is characterized by being carried out in conjunction with the registration of the parametric effects of the reflected harmonic magnetic field.

2. The method according to claim 1, characterized in that the property of pulsed magnetic fields and mechanical shock physical fields to penetrate deeply into the metal shell of the body of the object being detected is utilized, which results in localized malfunctions in the electronic circuits inside the object, and the operating mode in the form of characteristic "bursts" and changes in the level of reflected signals are recorded as additional information features.

3. A device for detecting search objects such as underwater robots and drones, comprising a magnetic measurement receiver (8) and a unit for recording the results of measuring the magnetic field strain from the search object (6) to determine the remanent magnetization, A device characterized by an electrical energy source (1), a magnetic impulse pulse field generator (2), a harmonic signal generator (3), a source of pulsed mechanical force collisions (4), a radiating magnetic frame antenna (5), a receiver (7) configured to receive paramagnetically modulated and reflected harmonic magnetic fields, an object distance meter (9), and a control module (10).

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