12 results about "Helmholtz coil" patented technology

The present application relates to a kind of low-frequency magnetic field generator for rat electromagnetic experiment and its uniform area measuring method, the method includes the following steps: S1, analysis display terminal calculates the magnetic induction intensity distribution of Helmholtz coil under given condition, and according to the change of magnetic induction intensity relative error determines the uniform area of magnetic field distribution, is recorded as reference area, corresponding boundary is reference boundary;S2, using magnetic field probe coil measures the magnetic induction intensity on reference boundary;S3, least square method is applied to obtain the measured boundary of magnetic field distribution uniform area;S4, according to the average absolute percentage error of magnetic induction intensity at measured boundary and reference boundary determines its actual uniform boundary;S5, analysis display terminal displays the actual uniform area of Helmholtz coil magnetic field distribution under given current amplitude and frequency, for rat electromagnetic experiment.Compared with prior art, the present application has the advantages of obtaining accurate magnetic field uniform area, reducing test workload and the like.

This invention relates to the field of geomagnetic vector measurement technology and proposes an in-situ rapid calibration method for a cubic magnetic gradient tensor measurement array. This invention utilizes a triaxial Helmholtz coil system to generate a constant magnetic field with random orientation and actively compensates for environmental magnetic drift. A hierarchical calibration algorithm is used to sequentially estimate sensor-level inherent errors and array-level alignment errors, and an evaluation framework based on tensor invariants is established to quantitatively analyze the calibration effect. Specifically, this includes: constructing a constant modulus random magnetic field, solving the hierarchical calibration algorithm, and evaluation and verification based on tensor invariants. This invention eliminates the need for mechanical array rotation, achieving in-situ rapid calibration in a static array state. It significantly suppresses pseudo-gradients introduced by channel inconsistencies, improving the stability of magnetic gradient tensor measurement by 3 to 5 orders of magnitude. It is applicable to magnetic anomaly detection and target localization scenarios in fields such as geological exploration, underwater tracking, and space magnetic surveying.

The application provides a seawater motion magnetic field characteristic measuring device, which comprises a composite structure pipeline, an excitation system and a measuring system; the composite structure pipeline is used for improving the motion speed of seawater; the excitation system adopts square Helmholtz coils which are arranged on the upper and lower sides of the composite structure pipeline respectively and generate a uniform magnetic field between the coils, and the magnetic field direction is perpendicular to the cuboid pipeline; the measuring system adopts a ring-shaped magnetic core induction coil, the resonant frequency of the ring-shaped magnetic core induction coil is tuned to the fundamental wave frequency of a PWM square wave signal through parallel matching capacitors, the in-band output response is improved, and the out-of-band interference is suppressed; a preamplifier, an analog switch and a low-pass filter jointly constitute a phase-locked amplification circuit, the analog switch is controlled by a PWM signal, and the seawater motion magnetic field signal under the action of an alternating field is extracted from the interference environment.

The application discloses a kind of micro-nano robot adaptive weighted double-layer PID magnetic control driving method and system, it is related to micro-nano robot control technical field, including: obtaining the multiple motion modes of micro-nano spiral robot, wherein micro-nano spiral robot adopts three-dimensional orthogonal helmholtz coil array driving;The posture and position of micro-nano spiral robot are monitored, according to multiple motion modes, by double-layer PID control based on weighted micro-nano spiral robot is followed path.This application can realize micron level positioning accuracy and millisecond level dynamic response in complex simulated physiological environment by fusing closed-loop feedback control, adaptive PID adjustment and trajectory planning algorithm.At the same time, the algorithm has high modular compatibility and scalability, different size configurations, different material spiral robots can be controlled, which provides a new solution for the driving control of spiral robot.

This invention provides a device and method for testing the mechanical parameters of lunar rocks based on electromagnetic catapults, relating to the field of deep space exploration technology. The device includes an electromagnetic catapult and braking module. The electromagnetic catapult and braking module includes a guide rod, with an impact rod at its head. From the tail to the head of the guide rod, a catapult section coil, a braking section coil, and an impact body are sequentially and spaced apart along the same axis on the outside of the guide rod body. The catapult section coil and the braking section coil are Helmholtz coils. The catapult section coil, the braking section coil, and an energy storage capacitor bank are connected in series. The capacitor bank is connected in parallel with a discharge resistor. The braking section coil is connected in series with a MOSFET driver module. This invention uses electromagnetic catapults, resulting in small impact energy deviation and overcoming the shortcomings of mechanical springs in energy storage instability under extreme environments.

This invention relates to the field of ion source technology and discloses a transmission system for a small negative high-voltage neutron source. The transmission system includes a transmission tube, a plasma electrode, an extraction electrode, a Helmholtz coil, and an aperture. The transmission tube has a vacuum channel, and the plasma electrode and the extraction electrode are located inside the vacuum channel, downstream of the plasma electrode in the beam transmission direction. The Helmholtz coil is located outside the transmission tube. This transmission system can overcome the technical problem of how to achieve 100 mA beam transmission and beam homogenization within a limited structural size for a small negative high-voltage neutron source. The Helmholtz coil and aperture can effectively suppress the space charge effect of the ion source, enhance the beam transmission efficiency, and improve beam homogenization. Simultaneously, it can reduce the target surface heat load, improve neutron yield, and increase the target's service safety and lifespan.

The application claims a kind of based on magnetic nano particle enhanced magnetic induction hemorrhagic cerebral apoplexy detection system, belong to biomedical engineering field cerebral disease detection and monitoring and physiological signal detection field, it includes: signal source, power amplifier, series resonance circuit, receiving coil, excitation coil, acquisition card and computer, wherein, the signal source is connected with power amplifier, the power amplifier is connected with series resonance circuit, the series resonance circuit is connected with receiving coil and excitation coil respectively, the receiving coil is connected with acquisition card, and the acquisition card is connected with computer;The application includes hardware series resonance circuit design, MAXWELL simulation coil design and helmholtz coil production, hardware system building and experimental test.The application proposes a kind of with high sensitivity can bed-side monitoring system, timely detection cerebral hemorrhage, and it has important significance for the discrimination of cerebral apoplexy type and related cerebral disease monitoring.

The invention discloses a magnetic micro-robot cluster task adaptive formation control method and system, and belongs to the technical field of micro-nano robot cluster control and tumor immunotherapy crossing. According to real-time imaging feedback, identifying current blood vessel environment characteristics, and judging a current task stage; generating a composite magnetic field sequence based on parameter limitation of the three-dimensional Helmholtz coil; establishing a prediction model based on the composite magnetic field sequence; evaluating a formation success rate; when the evaluated formation success rate is lower than 90%, online parameter optimization is carried out; and task adaptive formation control of the magnetic micro-robot cluster is realized. The method is used for solving the problems of single control dimension, lack of formation capability, no quantitative performance index and mismatching of a magnetic field system in the prior art, and realizes adaptive switching and accurate control of three task formation forms of the magnetic micro robot in different stages of a blood circulation system.

The application discloses a dynamic quantization axis control device for multi-axis inertial measurement, comprising an interference cavity, one atom source is arranged at each end of the interference cavity, two orthogonal laser groups and three pairs of mutually orthogonal Helmholtz coils are arranged outside the interference cavity. The application also discloses a dynamic quantization axis control method for multi-axis inertial measurement, according to a preset axis distribution time sequence, the atom source continuously emits cold atom groups to the interference cavity, the magnetic field generated by the Helmholtz coils and the start-stop of the laser groups are periodically switched, so that the quasi-synchronous measurement of two-axis inertial quantities is realized. The application can be quickly expanded to full-vector inertial measurement. By introducing a fast adiabatic shortcut magnetic field pulse rotation, using three-axis orthogonal magnetic field waveform control and anti-adiabatic compensation field design, the magnetic field direction switching is completed in sub-millisecond level, at the same time, the atom spin adiabatic follow-up quantum axis is ensured, the non-adiabatic transition and Zeeman phase shift accumulation are effectively inhibited, and the interference contrast and phase stability are ensured.

This invention discloses a method for testing and compensating the magnetic shielding effect of fiber optic inertial navigation systems, belonging to the field of magnetic shielding testing and compensation for inertial measurement units. The method includes: generating a controllable magnetic field using a triaxial Helmholtz coil; measuring the magnetic field strength and calculating the shielding effectiveness using internal and external magnetometers; acquiring multiple sets of test data under different magnetic field conditions to establish a mathematical model of the residual magnetic field and the output errors of the gyroscope and accelerometer; calibrating the sensitivity coefficient and constant zero bias using the least squares method; and measuring the internal residual magnetic field in real time during actual operation, calculating the estimated error, and subtracting it from the original output to achieve error compensation. This invention can quantitatively evaluate the magnetic shielding effect and significantly improve the output accuracy of fiber optic inertial navigation systems under magnetic field interference environments through error modeling and real-time compensation.

The present invention relates to the field of electromagnetic detection and provides a method for the enhanced detection of wake electromagnetic fields based on a circulating water basin. The present method comprises: the construction of a test setup for wake electromagnetic fields based on a circulating water basin, wherein the model to be tested is fixed in the flow channel of the circulating water basin; the arrangement of Helmholtz coils outside the circulating water basin to generate an enhanced background magnetic field; the periodic variation of the rotational speed of the drive unit and thus the periodic variation of the flow velocity in the circulating water basin; the measurement of the electric field and the magnetic field in the target area; and the processing and analysis of the obtained signals.

This invention discloses a magnetic field-assisted oriented Fe / h-BN layered soft magnetic composite material and its preparation method, belonging to the technical field of soft magnetic composite materials. The method includes ball milling iron powder to obtain flake-shaped Fe powder; ball milling and mixing the flake-shaped Fe powder with h-BN powder to peel the h-BN powder into single-layer or few-layer h-BN nanosheets, which are then uniformly coated onto the surface of the Fe powder; pressing the flake-shaped Fe powder under the assistance of a Helmholtz coil magnetic field to orient the flake-shaped Fe powder along the magnetic field direction to form a layered structure; and finally, obtaining the Fe / h-BN layered soft magnetic composite material by discharge plasma sintering. This invention constructs a layered magnetic permeability pathway by inducing the oriented arrangement of flake-shaped Fe powder using a magnetic field, combined with a two-dimensional insulating coating layer of h-BN, effectively suppressing mid-to-high frequency eddy current losses, maintaining high saturation magnetization and good permeability stability. The resulting Fe / h-BN layered soft magnetic composite material exhibits low magnetic loss, high saturation magnetization, and stable permeability under high-frequency conditions.