scholarly journals Validation of a Fast and Accurate Magnetic Tracker Operating in the Environmental Field

2021 ◽  
Author(s):  
Valerio Biancalana ◽  
Roberto Cecchi ◽  
Piero Chessa ◽  
Marco Mandalà ◽  
Giuseppe Bevilacqua ◽  
...  
Keyword(s):  
High Speed ◽  
Homogeneous Field ◽  
Practical Application ◽  
Time Performance ◽  
Magnetic Source ◽  
Precision Time ◽  
Position And Orientation ◽  
Magnetic Tracker ◽  
Best Fit ◽  
The Magnetic Field

We characterize the performance of a system based on a magnetoresistor array. This instrument is developed to map the magnetic field, and to track a dipolar magnetic source in the presence of a static homogeneous field. The position and orientation of the magnetic source with respect to the sensor frame is retrieved together with the orientation of the frame with respect to the environmental field. A nonlinear best-fit procedure is used, and its precision, time performance, and reliability are analyzed. This analysis is performed in view of the practical application for which the system is designed that is an eye-tracking diagnostics and rehabilitative tool for medical purposes, which require high speed ($\ge 100$~Sa/s) and sub-millimetric spatial resolution. A throughout investigation on the results makes it possible to list several observations, suggestions, and hints, which will be useful in the design of similar setups.

scholarly journals Validation of a Fast and Accurate Magnetic Tracker Operating in the Environmental Field

Instruments ◽  
2021 ◽  
Vol 5 (1) ◽  
pp. 11
Author(s):  
Valerio Biancalana ◽  
Roberto Cecchi ◽  
Piero Chessa ◽  
Marco Mandalà ◽  
Giuseppe Bevilacqua ◽  
...  
Keyword(s):  
High Speed ◽  
Homogeneous Field ◽  
Practical Application ◽  
Time Performance ◽  
Magnetic Source ◽  
Precision Time ◽  
Position And Orientation ◽  
Magnetic Tracker ◽  
Best Fit ◽  
The Magnetic Field

We characterize the performance of a system based on a magnetoresistor array. This instrument is developed to map the magnetic field, and to track a dipolar magnetic source in the presence of a static homogeneous field. The position and orientation of the magnetic source with respect to the sensor frame is retrieved together with the orientation of the frame with respect to the environmental field. A nonlinear best-fit procedure is used, and its precision, time performance, and reliability are analyzed. This analysis is performed in view of the practical application for which the system is designed that is an eye-tracking diagnostics and rehabilitative tool for medical purposes, which require high speed (≥100 Sa/s) and sub-millimetric spatial resolution. A throughout investigation on the results makes it possible to list several observations, suggestions, and hints, which will be useful in the design of similar setups.

scholarly journals Fast, Cheap, and Scalable Magnetic Tracker with an Array of Magnetoresistors

Instruments ◽  
2020 ◽  
Vol 5 (1) ◽  
pp. 3
Author(s):  
Valerio Biancalana ◽  
Roberto Cecchi ◽  
Piero Chessa ◽  
Giuseppe Bevilacqua ◽  
Yordanka Dancheva ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Geomagnetic Field ◽  
Inhomogeneous Field ◽  
Large Set ◽  
Magnetic Source ◽  
Data Output ◽  
Position And Orientation ◽  
Magnetic Tracker

We present the hardware of a cheap multi-sensor magnetometric setup, where a relatively large set of magnetic field components is measured in several positions by calibrated magnetoresistive detectors. The setup is developed to map the (inhomogeneous) field generated by a known magnetic source, which is measured and then discerned from the background (homogeneous) geomagnetic field. The data output from this hardware can be successfully and reliably used to retrieve the position and orientation of the magnetic source with respect to the sensor frame, together with the orientation of the frame with respect to the environmental field. Possible applications of the setup are briefly discussed, and a synthetic description of the methods of data elaboration and analysis is provided.

Experimental investigation and optimization on field shaper structure parameters in magnetic pulse welding

2021 ◽  
pp. 095440542110148
Author(s):  
Yingzi Chen ◽  
Zhiyuan Yang ◽  
Wenxiong Peng ◽  
Huaiqing Zhang
Keyword(s):  
Magnetic Field ◽  
High Speed ◽  
Light Metal ◽  
Magnetic Pulse ◽  
Cross Sectional ◽  
Magnetic Pulse Welding ◽  
Pulse Welding ◽  
Sectional Shape ◽  
Welding System ◽  
The Magnetic Field

Magnetic pulse welding is a high-speed welding technology, which is suitable for welding light metal materials. In the magnetic pulse welding system, the field shaper can increase the service life of the coil and contribute to concentrating the magnetic field in the welding area. Therefore, optimizing the structure of the field shaper can effectively improve the efficiency of the system. This paper analyzed the influence of cross-sectional shape and inner angle of the field shaper on the ability of concentrating magnetic field via COMSOL software. The structural strength of various field shapers was also analyzed in ABAQUS. Simulation results show that the inner edge of the field shaper directly affects the deformation and welding effect of the tube. So, a new shape of field shaper was proposed and the experimental results prove that the new field shaper has better performance than the conventional field shaper.

scholarly journals Solar wind and substorm excitation of the wavy current sheet

2009 ◽  
Vol 27 (6) ◽  
pp. 2457-2474 ◽  
Author(s):  
C. Forsyth ◽  
M. Lester ◽  
R. C. Fear ◽  
E. Lucek ◽  
I. Dandouras ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Solar Wind ◽  
Current Sheet ◽  
Pressure Pulse ◽  
Wind Pressure ◽  
Expansion Velocity ◽  
Solar Wind Pressure ◽  
Wave Models ◽  
Best Fit ◽  
The Magnetic Field

Abstract. Following a solar wind pressure pulse on 3 August 2001, GOES 8, GOES 10, Cluster and Polar observed dipolarizations of the magnetic field, accompanied by an eastward expansion of the aurora observed by IMAGE, indicating the occurrence of two substorms. Prior to the first substorm, the motion of the plasma sheet with respect to Cluster was in the ZGSM direction. Observations following the substorms show the occurrence of current sheet waves moving predominantly in the −YGSM direction. Following the second substorm, the current sheet waves caused multiple current sheet crossings of the Cluster spacecraft, previously studied by Zhang et al. (2002). We further this study to show that the velocity of the current sheet waves was similar to the expansion velocity of the substorm aurora and the expansion of the dipolarization regions in the magnetotail. Furthermore, we compare these results with the current sheet wave models of Golovchanskaya and Maltsev (2005) and Erkaev et al. (2008). We find that the Erkaev et al. (2008) model gives the best fit to the observations.

Some Guidance for Hull Form Selection for SWATH Ships

1988 ◽  
Vol 25 (04) ◽  
pp. 239-252
Author(s):  
G. Robed Lamb
Keyword(s):  
High Speed ◽  
Early Stage ◽  
The United States ◽  
Practical Application ◽  
Hull Form ◽  
Stage Design ◽  
Seakeeping Performance ◽  
The World ◽  
Selection For ◽  
Early Stage Design

Even though in 1987 there were only a dozen SWATH (smali-waterplane-area twin-hull) craft and ships afloat around the world, word of their markedly superior seakeeping performance is spreading rapidly. The number of SWATH vessels is likely to double within five years. As in many other areas of technology, the United States and Japan are the acknowledged leaders in the development and practical application of the SWATH concept. This paper reviews the characteristics of existing SWATH craft and ships from the standpoint of the stated seakeeping objective. Hull form differences between four SWATH craft and ships, including the Navy's SSP Kairnalino, are analyzed and interpreted. Important considerations for the early-stage design of a SWATH ship are discussed. Differences in the range of feasible hull form geometries for coastal areas and unrestricted ocean operations, and for low-speed versus moderately high-speed applications, are pointed out.

A Novel Flux-Weakening Structure of High-Speed Permanent Magnet Motor Based on the Soft Ferrite

2013 ◽  
Vol 694-697 ◽  
pp. 1508-1511
Author(s):  
Xing Hua Wang ◽  
Xue Yuan Lin ◽  
Ming Hui Li ◽  
Yu Chen ◽  
Cheng Hui Zhang
Keyword(s):  
Permanent Magnet ◽  
High Speed ◽  
High Resistivity ◽  
Permanent Magnet Motor ◽  
Soft Magnetic ◽  
Low Loss ◽  
Magnetic Resistance ◽  
The Magnetic Field ◽  
Soft Ferrite ◽  
Flux Weakening

Soft ferrite has the characteristics of high permeability, high resistivity, low loss. Based on this, a new flux-weakening structure of high-speed permanent magnet motor was presented. The structure relies on changing the saturation of soft magnetic ferrite to change the equivalent magnetic resistance of permanent magnet magnetic circuit in the motor, so the main flux of the permanent magnet motor can be reduced. By the 3D Finite Element analyses, the magnetic field distribution characters in the air gap can be pointed out. The analysis results prove the flux-weakening method is presented in this paper is correct and feasible. It can provide a practical flux-weakening method of the high-speed PM motor.

scholarly journals Numerical Response Surfaces of Volume of Ablation and Retropulsion Amplitude by Settings of Ho:YAG Laser Lithotripter

2018 ◽  
Vol 2018 ◽  
pp. 1-11
Author(s):  
Jian J. Zhang ◽  
Jonathan Rutherford ◽  
Metasebya Solomon ◽  
Brian Cheng ◽  
Jason R. Xuan ◽  
...  
Keyword(s):  
Pulse Energy ◽  
Pulse Width ◽  
High Speed ◽  
Operation Time ◽  
Laser Lithotripsy ◽  
Pulse Number ◽  
Response Surfaces ◽  
Ho:Yag Laser ◽  
Energy Pulse ◽  
Best Fit

Objectives.Although laser lithotripsy is now the preferred treatment option for urolithiasis due to shorter operation time and a better stone-free rate, the optimal laser settings for URS (ureteroscopic lithotripsy) for less operation time remain unclear. The aim of this study was to look for quantitative responses of calculus ablation and retropulsion by performing operator-independent experiments to determine the best fit versus the pulse energy, pulse width, and the number of pulses.Methods.A lab-built Ho:YAG laser was used as the laser pulse source, with a pulse energy from 0.2 J up to 3.0 J and a pulse width of 150 μs up to 1000 μs. The retropulsion was monitored using a high-speed camera, and the laser-induced craters were evaluated with a 3-D digital microscope. The best fit to the experimental data is done by a design of experiment software.Results.The numerical formulas for the response surfaces of ablation speed and retropulsion amplitude are generated.Conclusions.The longer the pulse, the less the ablation or retropulsion, while the longer pulse makes the ablation decrease faster than the retropulsion. The best quadratic fit of the response surface for the volume of ablation varied nonlinearly with pulse duration and pulse number.

Research of High-Speed Railway Running Economic Benefit Based on Gray Model

2012 ◽  
Vol 253-255 ◽  
pp. 1273-1277
Author(s):  
Xue Dong Du ◽  
Na Ren
Keyword(s):  
Data Analysis ◽  
Prediction Model ◽  
Economic Benefit ◽  
High Speed ◽  
Accurate Prediction ◽  
Gray Model ◽  
Practical Application ◽  
High Speed Railway ◽  
Railway Stations ◽  
Train Operation

The research of high-speed railway running economic benefit is important to timely know well the train operation state for the railway administration. A prediction model of high-speed railway running economic benefit is proposed in this article based on Gray model. The Gray model is a good example to make accurate prediction of the development of matters. According to the data analysis of Beijing and Shanghai railway stations, we can know that the result of prediction model is accurate, so the prediction based on Gray model is scientific and reasonable in the practical application.

Design of a frictional–electromagnetic compound disk brake for automotives

2019 ◽  
Vol 234 (4) ◽  
pp. 1113-1122
Author(s):  
Shan Huang ◽  
Jiusheng Bao ◽  
Shirong Ge ◽  
Yan Yin ◽  
Tonggang Liu
Keyword(s):  
High Speed ◽  
Test Bench ◽  
Theory Model ◽  
Comsol Multiphysics ◽  
Simulation Test ◽  
Braking Performance ◽  
Brake Pads ◽  
Disk Brake ◽  
Braking Torque ◽  
The Magnetic Field

According to the disadvantages of serious wear and heat fade of friction pad in frequent and high speed braking of friction brakes, and the insufficient power of electromagnetic brakes in low speed braking, a novel frictional-electromagnetic compound disk brake which combines both of these two brake principles is proposed for automotives in this paper. The excitation coils are designed based on the Zhang Yicheng theory model, and the compound brake prototype is manufactured based on the self-made magnetic brake pads and existing automotive brakes. The magnetic field and dynamic of the brake are simulated by using COMSOL Multiphysics software. The frictional–electromagnetic compound brake tests are implemented on the reconstructive disk brake simulation test bench. The experimental results show that the friction braking torque accounts for more than 90% of the compound braking torque in the process of compound braking, and the trend of the change is the same as that of the compound braking torque. When the initial braking speed exceeds 75 km/h, the electromagnetic braking torque does not increase with the increase in speed, instead, it decreases slightly because of demagnetization. The designed frictional–electromagnetic compound disk brake has good braking performance.

A Practical Application of Air Lubrication On a Small High Speed Boat

2001 ◽  
pp. 113-118
Author(s):  
Jinho Jang ◽  
Jun Ahn ◽  
Jaesung Kim ◽  
Jung-Chun Suh ◽  
Hyochul Kim ◽  
...  
Keyword(s):  
High Speed ◽  
Practical Application ◽  
Air Lubrication
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