Osamu Shimizu

In this study, a novel system named the third-generation wireless in-wheel motor (WIWM-3), which has a dynamic wireless power transfer (DWPT) system, is developed. It can extend the cruise range, which is one of the key specifications of electric vehicles. DWPT also reduces CO2 emission as the driving resistance is reduced due to light weight of the batteries. In this study, CO2 emission by an internal combustion vehicle, a long range drivable electric vehicle with the same cruise range, and an

The soft magnetic properties of the FeZrN ternary system were studied in association with excess nitrogen (N) in films. The proportion of excess N (EN) is defined (z−y)/[x+(z−y)]×100 for the film composition expressed FexZryNz. This is because the advent of soft magnetism, in this system, is assumed to be due to suppression of grain growth of α-Fe by ZrN precipitated in grain boundaries, thus causing a ‘‘nanocrystalline effect.’’ This means that N exceeding the amount of Zr is considered ‘‘exces

The effects of particle orientation on the performance of barium ferrite particulate media were investigated by both simulation and experiment. Orientation to either the longitudinal or the perpendicular direction improved performance compared to unoriented media. The experiment showed that small increase of the squareness ratio of the perpendicular direction from 0.69 to 0.84 boosted the signal-to-noise ratio (SNR) by 1.5 dB at the linear recording density at 600 kbpi. Experimental results agre

The thermal stability factor (K <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">u</sub> V/k <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">BT</sub> , where K <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">u</sub> , V, k <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">B</sub> , and T are the magnetic anisotrop

This study experimentally compared barium ferrite with conventional metal particulate media in terms of their chemical corrosion resistance and thermal stability−two important factors determining archival stability. The results confirmed the superior properties of barium ferrite even at the smaller particle sizes necessary for future high-capacity media. The thermal decay rate of the barium ferrite media was in the range from 0.04 to 0.07 dB/decade, and the degradation of saturation magnetizatio

Dynamic wireless power transfer (WPT) can solve the short cruising range problem of electric vehicles; moreover, it makes electric vehicles more efficient due to reducing heavy battery of electric vehicles. However to be stopped transmission of dynamic WPT by foreign matter objects is one of the major problems of dynamic WPTs. Prevention of the entry of foreign objects between the transmitter and receiver coils is the best method to increase the opportunity WPT and energy of WPT. This article ai

I-H loops of <111>, <110> or <100> oriented single crystal films of Fe base alloys were obtained by calculation in which the single domain model is used with the total energy including shape anisotropy, magnetocrystal anisotropy and magnetic field energy. This calculation shows that the coercive force of <111> oriented film is as small as 50 [A/m], which is less than a hundredth of those for <110> or <100> oriented film. And K1 (magnetic anisotropy constant) dependence and shape dependence of co

Laborsaving is a major issue in production. In an automotive production line, a yard that is used as a temporary storage for vehicles before shipping. The vehicle-loading robot that operates autonomously has been proposed to automate the alignment of vehicles in the yard instead of human driving. In this study, the dynamic wireless power transfer system that includes the structure of the roadside for the vehicle-loaded robot is proposed. It is proven that the transmitter coil has enough durabili

Abstract Laborsaving is a major issue in production. In an automotive production line, a yard that is used as a temporary storage for vehicles before shipping. The vehicle‐loading robot that operates autonomously has been proposed to automate the alignment of vehicles in the yard instead of human driving. In this study, the dynamic wireless power transfer (DWPT) system that includes the structure of the roadside for the vehicle‐loaded robot is proposed. It is proven that the transmitter coil has

A measurement method of the saturation magnetostriction constant is introduced. The magnetostriction was determined without using the thickness and Young's modulus of the films. The annealed film deposited on a substrate which has the uniaxial anisotropy of thermal expansion has the magnetic anisotropy induced by thermal stress. The stress anisotropy was determined by interpolation or extrapolation. And the magnetic anisotropy induced by magnetostriction was measured from B-H loops. The saturati

We surveyed the history of using metal particulate media in linear tape systems to enhance cartridge capacity, discussed the metal particulate media limitations, and introduced advanced barium-ferrite-particulate-media-based magnetic tape technology, focusing on the use of magnetic particles, surface profile design, and particle orientation control. The increase in cartridge capacity has been accelerated by combining barium ferrite particles with ultrathin layer coating technology and by control

Abstract Short cruise range is a major issues in electric vehicles, and dynamic wireless power transfer (WPT) has been proposed to solve this problem. In this study, a new dynamic power transfer system is introduced, called the hird generation wireless in‐wheel motor, that integrates the drive circuit and motor. Additionally, a methodology of the transmitter and receiver coil design that can calculate inductance and resistance of the rectangular spiral coils in a fast manner is proposed. It cons