METHOD OF DETECTING UNDERWATER FERROMAGNETIC OBJECTS AND SYSTEM FOR DETECTING UNDERWATER FERROMAGNETIC OBJECTS Russian patent published in 2017 - IPC G01V3/08 

FIELD: physics, instrument-making.

SUBSTANCE: invention relates to reconnaissance using magnetic fields and can be used to detect underwater ferromagnetic objects. Method comprises towing two magnetic field sources along an investigation strip. The boundaries of the investigation strip are set by spreading ferromagnetic material, formed in the form of 1 m³ heaps, placed at a distance of 80-170 m from each other along the axis of the boundary to form a quadrangle. A unit for controlling alternate operation of the towed magnetic field sources is used to record the overall magnetic field of the towed sources and the ferromagnetic heaps with a primary three-component magnetic field converter. Method includes amplifying and converting the detected signals of the overall magnetic field of the towed sources and the ferromagnetic heaps with a secondary converter. The amplified and converted signals of the overall magnetic field of the towed sources and the ferromagnetic heaps are transmitted to a computing unit. The computing unit determines the signal caused by the presence of ferromagnetic heaps or an underwater ferromagnetic object. The signal is transmitted from the computing unit to an actuating unit followed by relaying thereof to the control unit. The control unit provides movement of the towed magnetic field sources within the boundaries of the investigation strip by determining signal coordinates in a navigation module. Method includes preliminary bathymetric survey using a multi-beam echo sounder, acoustic probing of the bottom relief using side-scan sonar, based on the echo and shadow contacts, identifying the detected underwater objects, mapping the bottom relief with identification of watershed lines and weir lines, further probing of the detected object using a laser beam source with transmission of the image to a video system with highlighting of the boundaries on the image using a Sobel operator and a Canny detector. The system for detecting underwater ferromagnetic objects consists of a magnetic field measuring system, which includes two towed magnetic field sources respectively connected by conducting ropes to a power unit through a control unit, two towed primary three-component magnetic field converters, respectively connected by conducting ropes to the secondary converter through the control unit, a computing unit, the input of which is connected to the output of the secondary converter, and the output is connected to the input of the actuating unit, a multi-beam echo sounder and side-scan sonar, which are connected through the control unit and the secondary converter to the computing unit, characterised by that it includes a laser beam module, a video system, an image processing unit, which is connected through the control unit to the laser beam module, the multi-beam echo sounder, the side-scan sonar and the computer.

EFFECT: invention increases accuracy of detecting underwater objects.

3 cl, 6 dwg