227 results about "Magnetic anomaly" patented technology

An imaging system suitable for use with a vehicle based global positioning system includes an imaging sensor and a control. The imaging sensor is positioned at the vehicle and may face generally forwardly with respect to the direction of travel of the vehicle. The control may be operable to provide a record of vehicle movement since the last position data derived from the vehicle based global positioning system. The imaging system may also or otherwise be suitable for use with a vehicle based magnetic compass system. The imaging system may be operable in combination with a magnetic field sensor of the magnetic compass system to provide a substantially continuously calibrated heading indication, which is substantially resistant to local magnetic anomalies and changes in vehicle inclination. The imaging sensor may be associated with one or more other accessories of the vehicle.

A system and method for determining a position of a remote object comprising inertial sensors and three axis magnetic sensor, together with a target sighting device aligned with the observation platform to determine a target line of sight and a target range finder to determine a distance to the target along the line of sight. A GPS receiver may be included for determining an observation platform position and orientation, The three axis magnetic sensor provides both magnetic north and vertical attitude information for improved rapid initialization and operation in motion. Magnetic anomaly information is detected by comparing IMU and magnetic navigation information and by other methods. Target identification may be determined by a human operator and / or by computer. The system may be integrated with a weapon system to use weapon system sights. The system may be networked to provide target location and / or location error information to another identical unit or a command information system.

An un-manned airborne vehicle (UAV), for acquiring aeromagnetic data for geophysical surveying at low altitude on land or over water, comprising an extended fuselage that is adapted to hold and maintain magnetometer and a magnetic compensation magnetometer at a minimum distance from the avionics and propulsion systems of the UAV. The magnetometer measures magnetic anomalies and the magnetic compensation magnetometer measures magnetic responses corresponding to the pitch, yaw and roll of the UAV. A data acquisition system stores and removes the magnetic response measurements from the magnetic anomaly measurements. The data acquisition system also stores a survey flight plan and transmits the same to the avionics system. The generator of the UAV is shielded and the propulsion system is stabilized to reduce magnetic and vibrational noises that can interfere with the operation of the magnetometer.

A magnetic anomaly sensing system and method uses at least four triaxial magnetometer (TM) sensors with each of the TM sensors having X,Y,Z magnetic sensing axes. The TM sensors are arranged in a three-dimensional array with respective ones of the X,Y,Z magnetic sensing axes being mutually parallel to one another. The three-dimensional array defines a geometry that forms at least one single-axis gradiometer along each of the X,Y,Z magnetic sensing axes. Information sensed by the TM sensors is to generate scalar magnitudes of a magnetic anomaly field measured at each of the TM sensors, comparisons of the scalar magnitudes to at least one threshold value, distance to a source of the magnetic anomaly field using the scalar magnitudes when the threshold value(s) is exceeded, and a magnetic dipole moment of the source using the distance.

A magnetic anomaly surveillance system includes triaxial magnetometer (TM) sensors arranged at known locations in an array. A processor coupled to the TM sensors generates a scalar magnitude of a magnetic anomaly field measured at each of the TM sensors. The scalar magnitude is indicative of a spherical radius centered at the known location associated with a corresponding one of the TM sensors. The processor also generates a comparison between each scalar magnitude and a threshold value. The processor then determines at least one magnetic anomaly location in the coordinate system via a spherical trilateration process that uses each spherical radius and each scalar magnitude associated with selected ones of the TM sensors for which the threshold value is exceeded. One or more output devices coupled to the processor output data indicative of the one or more magnetic anomaly locations.

A system for tracking a moving magnetic target uses a magnetic anomaly sensing system to continually determine magnetic gradient tensors associated with the target and converts the magnetic gradient tensors to gradient contraction scalars. A processor uses the magnetic gradient tensors and gradient contraction scalars to determine a minimum of bearing and range to the target. A velocity of the target is determined using the determined bearing and range at two points in time as the target is moving. To continually track with the moving target, the processor determines adjustments in elevation and azimuth using the magnetic gradient tensors and gradient contraction scalars along with bearing, range and determined velocities of the target. The processor can include a routine that determines range while accounting for asphericity errors introduced by the aspherical nature of constant magnetic gradient contours associated with the target.

The invention provides an intelligent parking monitoring and management system and a vehicle in-position detection method under a parking mode. The system comprises a vehicle detector, a wireless communication unit and a parking monitoring and management center, wherein the vehicle detector comprises an infrared detection module and a GMI detection module; the vehicle detector is used for carrying out comprehensive processing on a vehicle existence signal, which is detected by the infrared detection module, of a parking space and a vehicle disturbance geomagnetic field magnetic anomaly signal, which is detected by the GMI detection module, of the parking space, generating vehicle information of the parking space, and sending the vehicle information of the parking space to the wireless communication unit; and the parking monitoring and management center is used for processing the received vehicle information of the parking space, and carrying out monitoring, management and charge management on the parking space information according to a processing result. The intelligent parking monitoring and management system and the vehicle in-position detection method under the parking mode are applicable to the technical field of vehicle detection.

A magnetic anomaly sensing system uses triaxial magnetometer (TM) sensors arranged in a three-dimensional array. A processor coupled to the TM sensors generates partial gradient contraction data, and complete gradient tensor data and corresponding complete gradient contraction data. The generated data can be used to align the three-dimensional array with a magnetic target. Once the three-dimensional array is aligned with the magnetic target, the generated data can be used to uniquely determine (i) distance to the magnetic target, (ii) position of the magnetic target relative to the three-dimensional array, and (iii) the magnetic dipole moment of the magnetic target.

The present invention provides an un-manned airborne vehicle (UAV), for acquiring aeromagnetic data for geophysical surveying at low altitude on land or over water, comprising an extended fuselage that is adapted to hold and maintain magnetometer and a magnetic compensation magnetometer at a minimum distance from the avionics and propulsion systems of the UAV. The magnetometer measures magnetic anomalies and the magnetic compensation magnetometer measures magnetic responses corresponding to the pitch, yaw and roll of the UAV. A data acquisition system stores and removes the magnetic response measurements from the magnetic anomaly measurements. The data acquisition system also stores a survey flight plan and transmits the same to the avionics system. The generator of the UAV is shielded and the propulsion system is stabilized to reduce magnetic and vibrational noises that can interfere with the operation of the magnetometer.

A magnetic anomaly homing system and method utilize an array of four triaxial magnetometer (TM) sensors coupled to a non-magnetic platform. The four TM sensors are positioned at the vertices of a rectangular parallelogram. The magnetic field sensed at the four TM sensors is processed to generate complete gradient tensors and corresponding scalar gradient contractions thereof for four two-axis gradiometers formed by the array. The scalar gradient contractions define guidance control parameters used to steer the platform toward the magnetic anomaly.

A system and method for magnetic anomaly guidance is provided. Triaxial magnetometer (TM) sensors are positioned at the vertices of an arrangement with an axis of the arrangement, being defined between each pair of the vertices. The arrangement is positioned on a support such that one of the X,Y,Z magnetic sensing axes for all of the sensors defines a forward direction of movement. The sensed magnetic field's X,Y,Z components of the TM sensors are processed to generate a partial gradient contraction associated with each axis of the sensor arrangement. Relationships between the partial gradient contractions are used to generate steering control commands for use by a steering system that is coupled to the support.

A portable magnetic anomaly sensing system includes a non-magnetic support structure defined by a rigid beam and a rigid frame coupled thereto. Triaxial magnetometer (TM) sensors are rigidly coupled to the frame with one TM sensor being positioned at each vertex of a cubic space. Each TM sensor is positioned such that all respective X,Y,Z magnetic sensing axes are mutually parallel to one another. A data acquisition system is mechanically coupled to the beam such that any magnetic elements of the data acquisition system do not adversely affect accuracy of the TM sensors. The data acquisition system samples the sensed magnetic field data from all TM sensors synchronously with a timing signal. A processor is mechanically coupled to the beam such that any magnetic elements of the processor do not adversely affect accuracy of the TM sensors. The processor applies a magnetic scalar triangulation and ranging (STAR) processing scheme to the digitized magnetic field data in order to determine a position vector and a magnetic moment vector. One or more output generation devices are used to generate a human-discernable output to the position vector and the magnetic moment vector.

The invention provides a geophysical prospecting technical method for recognizing the lithology of petrosilex by using the combined characteristics of gravity-magnetic-electronic anomaly, which comprises the following steps of collecting and recording the physical characteristics of drill core; carrying out cluster analysis on the density, magnetic susceptibility and resistivity of rock by using k-means clustering and obtaining the clustering code of the drill core; carrying out gravity and magnetic anomaly stripping to the gravity and magnetic prospecting result for obtaining the anomaly and adopting the same clustering to conduct three-dimensional anomaly coding; and combining the clustering code of the physical characteristics of rock with gravity-magnetic-electronic anomaly code for reflecting the lithology of each petrosilex in an exploratory area. By developing the method for recognizing the lithology of petrosilex by using integral gravity-magnetic-electronic from qualitative speculation to quantitative statistics, the invention reduces human subjective factors from experience, avoids the situation that different geological interpreters obtain different results and improves the recognition effect of petrosilex.

The invention discloses an underwater cultural relic integrated detection device based on an ROV platform, which includes a deck device and an underwater integrated detection device, and belongs to the technical field of marine detection. Deck installations include the mother ship, GPS system, ultra-short baseline transceiver and ROV console. The underwater detection device integrates magnetometer, multi-beam sonar, side-scan sonar, high-definition camera, shallow stratum profiler (shallow profiler) and ultra-short baseline acoustic beacon on the ROV platform. The magnetometer is used to measure the magnetic anomalies in the detection area and roughly determine the location of the underwater cultural relics. The shallow profiler is used to describe the cross-sectional structure of the underwater strata, which is used to detect the location of cultural relics buried below the mud surface. Multi-beam sonar and side-scan sonar are used to provide high-resolution underwater acoustic images, combined with high-definition cameras to detect the location of cultural relics on mud surfaces. The device of the invention integrates and fuses various sensor information, realizes the visualized and refined real-time detection of underwater cultural relics, and improves the detection efficiency of underwater cultural relics archaeological operations.

The invention provides a standard framework-based method for quick three-dimensional gravity and magnetic inversion for physical properties in geophysical exploration. The method comprises: gridding gravity and magnetic data first and then converting the data grid into a square node grid; subdividing lower haft space and performing standard framework quick forward calculation and storage; solvingsquare roots of a framework coefficient of a calculation point of a framework central cylinder to obtain a bin inversion coefficient array; performing expansion calculation for quick extrapolation; obtaining a three-dimensional gravity and magnetic anomaly data volume after plane gravity and magnetic anomaly separation; performing inversion physical property numerical range constraint and field level constraint; and obtaining a high-accuracy inversion model by a forward process. The method can reflect the three-dimensional density and magnetic susceptibility distribution of an underground geologic body, solves actual geological problems of a complex region, and has high-efficiency, quick, reliable, effective and practical effects.

The invention discloses a tracking and positioning method of an H-shaped scalar sensor array on a magnetic target.The method comprises the following steps that firstly, five magnetic sensors are used for structuring an H-shaped array on the water surface or underwater; secondly, the sensors in the H-shaped array are used for measuring the magnetic anomaly delta B generated by the magnetic target; thirdly, a magnetic dipole model is structured, and a magnetic field (the symbol is shown in the description) generated by the magnetic target at a measurement point is obtained; fourthly, the relation between the magnetic anomaly delta B and the position information (x, y, z) of the magnetic target is established; fifthly, magnetic anomaly data of the five magnetic sensors in the array is coupled; sixthly, the position information of the magnetic target is solved with a particle swarm algorithm, and tracking and positioning of the target are achieved.The detection method is easy to implement, high in positioning precision and long in positioning distance.

The invention provides a magnetic target tracking method based on a magnetic anomaly gradient. Through carrying out matrix transformation on the magnetic anomaly gradient, a unit direction vector of a target magnetic moment is separated, an optimization problem is formulated to estimate the position and magnetic parameters of the target, and through constructing a special fitness function, a particle swarm optimization algorithm is used to solve the target parameters. According to the target tracking method based on the magnetic anomaly gradient, a new idea is provided for target positioning by using geomagnetic total field information, the method can solve the information of moving target velocity, and certain reference meaning is realized in positioning and tracking of the magnetic target.

The invention discloses a method for comprehensive recognition of igneous rocks by employing gravity, magnetism, electromagnetism, and earthquake data. The method includes steps: building templates of different igneous rocks and stratum physical properties; performing forward modeling of gravity, magnetism, electromagnetism, and earthquake, and making clear of response characteristics and rules; performing gravity and magnetism anomaly extraction of the planes of the igneous rocks and weak anomaly enhancement processing, and explaining and dividing distribution zones and range of the planes of the igneous rocks; performing electrical and seismic profile data igneous rock target processing explanation and making clear of the distribution rule of the igneous rocks in the vertical direction; performing combined inversion of gravity, magnetism, electromagnetism, and earthquake data profile, and building a vertical distribution frame of the igneous rocks; developing three-dimensional inversion of the physical properties of the igneous rocks with gravity and magnetism anomalies by employing the profile combined inversion result and drilling data as the constraint condition and with the combination of plane distribution of the igneous rocks; and recognizing the space distribution and lithological and lithofacies distribution rules of the igneous rocks in a comprehensive manner with the combination of physical property combined characteristics of different igneous rocks according to the three-dimensional distribution of the physical properties. According to the method, comprehensive recognition of the igneous rocks is realized by employing various data, and the reliability is higher compared with the recognition of the igneous rock by employing single data.

The invention proposes a submarine locating method based on the spatial gradient of a magnetic field at two detection locations, and belongs to the fields of long-range submarine detection and magnetic dipole locating. The method includes the steps of first, forming a magnetic anomaly detection array using a plurality of single-axis vector magnetometers; measuring, by using the magnetic anomaly detection array, the magnetic field respectively at an initial detection location and a second detection location reached through a preset path, and obtaining a gradient tensor matrix and all the independent components thereof of a submarine additional magnetic field at each of the two detection locations; and according to an expression of the gradient tensor of the submarine additional magnetic field, substituting all the independent components of the gradient tensor matrix of the submarine additional magnetic field at each of the two detection locations to obtain and solve a locating equation, finally obtaining location information of the submarine and completing locating. The method can locate the submarine remotely in the background of a changing geomagnetic field, avoids the influence of diurnal variation in the geomagnetic field, and has high locating accuracy.

The present invention discloses an autonomous magnetic tomography method (MTM) and device for magnetographic identification and magnetographic analysis of mechanical flaws and defects along structures located deep in the sea or otherwise located underwater and further underground. The invention optimizes the inspection and maintenance processes of extended metallic constructions, e.g., pipelines. The device is based on the inverse magnetostrictive effect (i.e., the Villari effect)—the variation of a material's magnetic susceptibility under applied mechanical stress. The changes in magnetic susceptibility result in distribution of a magnetic field gradient along a structure's surface area, thus providing information about the presence and the value of the magnetic field anomaly at a given and precise location on the structure. The device and method is capable of autonomous and offline operation underwater at depths up to 1,500 meters below sea level.

A brushless permanent-magnet direct current motor has a permanent magnet which is magnetized to create an offset angle between detent and mutual torques for providing sufficient starting torque for all relative orientations between the stator and the rotor of the motor. This is accomplished by providing a permanent magnet in which the global magnetization of the magnet has been disrupted by the application of a local magnetic field to a portion of the magnet, thereby to provide a magnetic anomaly in the global magnetization. Also, a method of magnetization of the magnet is described.

The invention belongs to the field of underwater geomagnetic aided navigation, and particularly relates to an underwater vehicle all-attitude determination method based on magnetic gradient tensor measurement. The method comprises the steps of: under a carrier system, establishing a three-dimensional rectangular coordinate system to obtain five components of magnetic gradient tensor; extracting five isolated components of the magnetic gradient tensor under a geographical system from the prestored magnetic gradient tensor database; substituting the results into a non-linear equation set about q0, q1, q2 and q3; substituting quaternion q0, q1, q2 and q3 to a transformation matrix between a substitution carrier system and the geographical system to obtain the estimated value of a pitch angle theta. The underwater vehicle locating technology based on magnetic anomaly inversion has the characteristics of being low in cost, high in sensitivity, high in anti-interference capability, free from accumulative error and the like; the problem that a single magnetometer can not independently determine the attitude by depending on the geomagnetic field can be solved; an independent and concealed way is provided for underwater vehicle attitude estimation.

The invention discloses a depth-varying-to-density earth crust expansion coefficient thermal calibration gravity anomaly retrieval method. In the calculation process of a gravity retrieval earth crust expansion coefficient, a lithosphere thermal gravity anomaly calibration and depth constraint strategy is introduced, according to an iterative computation method of multiple parameter constraints such as a submarine topography, a sedimentary thickness, magnetic anomaly, an ocean age isochron and earthquake reflection and refraction, a distortion effect, caused by earth crust density changes resulted from lithosphere thermal disturbance, on gravity interpretation is corrected, and a basis is provided for knowing earth crust expansion and cracking processes.

The invention belongs to the geophysical gravity and magnetic data processing field and relates to a method for quickly inversing the spatial position of an underground geologic body. The method includes the following steps that: step 1, magnetic measurement data are obtained; step 2, measuring point anomaly Delta T values are obtained; step 3, gridding processing is performed on the measuring point anomaly Delta T values; step 4, a reduction-to-pole anomaly Delta T value grid and an X-direction, Y-direction and Z-direction derivative grid are obtained; step 5, the grids are segmented; step 6, Euler solutions in small grids are obtained; step 7, a small grid Euler solution set is extracted; and step 8, a final interpretation result map is obtained. With the method provided by the technical schemes of the present invention adopted, inversion speculation can be performed on the underground geologic body, so that the actual geological characteristics of the underground geologic body can be reflected, the distribution law of the underground geological body can be effectively evaluated, and therefore, underground mineral resources can be rapidly and accurately explored. The method is of great significance for geological prospecting work.

The invention belongs to the field of underground pipeline detection, and particularly relates to a buried iron pipeline detection and accurate positioning method and device based on magnetic anomaly vertical component analytic signal detection. The method particularly comprises the steps that multiple parallel detection paths are delimited on the ground of a detected region, magnetic anomaly analytic signal detectors are used for forming a linear array, magnetic anomaly vertical component analytic signals caused by buried iron pipelines are detected along the delimited tracks, four single-axis magnetic field sensors measure magnetic anomaly vertical components simultaneously, an analytic signal at the center of the cross is obtained through calculation and uploaded to a computer, detection surface analytic signal strength distribution is drawn on the computer, and existence and horizontal positions and orientations of the underground iron pipelines are indicated in a graph visualization mode. According to the buried iron pipeline detection and accurate positioning method and device, pipeline detection positioning is accurate, the use cost is low, instruments are easy to manufacture, and the economic benefit is significant.

The invention discloses a gravity and magnetic potential field analytic continuation method based on the spatial domain. The gravity and magnetic potential field refers to a gravity field or a magnetic field. The analytic continuation refers to a method of calculating the gravity field or magnetic field on other curved surfaces (including flat surfaces) by the gravity field or magnetic field on anobservation surface. The solution to the analytic continuation has two ideas including the spatial domain and the frequency domain. The analytic continuation method is a novel method for the spatialdomain, can directly continue the magnetic anomaly data of aeromagnetic measurement down to a ground enhanced magnetic anomaly signal, and can also continue the ground observation data up to a highersurface to highlight a deep field feature. The method can continue the abnormal data observed by any curved surface to another arbitrary curved surface, breaks through the limitation that the continuation surface in the frequency domain method must be a flat surface, and solves the singular point problem in the spatial domain analytical continuation method.

The invention provides a magnetic sensor array based rotation-movement magnetic anomaly target detection device and method. The device comprises a magnetic sensor array, a rotation mechanism, a rotation angle collection module, a GPS module, a signal collection module, a data processing module and a power supply. The geographic coordinate of a detected target is determined according to magnetic field information, collected by the magnetic sensor array, of the magnetic anomaly target, the rotation angle of the rotation mechanism, and the real-time geographic position of the magnetic sensor array. Dynamic measurement is carried out by circular motion, more comprehensive magnetic anomaly information is obtained, and a positioning result is more accurate.

The invention discloses a single-point positioning method for a magnetic target based on total magnetic field gradient and magnetic tensor modulus gradient. According to the method, the modulus of thetotal magnetic field gradient and the modulus of the magnetic tensor modulus gradient are acquired through a cubic magnetic detector, and then the analytical solutions of the orientation of the magnetic target and the size of a magnetic moment are gained through simultaneous equations. The magnetic target single-point positioning method provided by the invention can effectively avoid the problemof inaccurate positioning caused by relative rotation and relative motion of the magnetic target and the magnetic detector on the basis of rotation invariance of the total magnetic field gradient andthe magnetic tensor modulus gradient, and has important practical significance in application to positioning of a magnetic anomaly target in a specific scene.