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Linear oscillatory actuators have been used in a wide range of applications because they have a lot of advantages. Additionally, multi-degree of freedom resonant actuators have been developed. The purpose of this paper is to propose a novel three-degree-of-freedom resonant actuator resonant actuator that is driven in three directions. The dynamic characteristics are clarified through finite element analysis and measurement.

A novel three-degree-of-freedom resonant actuator resonant actuator consists of a cross-shaped mover, a stator and five excitation coils. The magnetic structure of this actuator is geometrically similar to that of general permanent magnet synchronous motor. Therefore, vector control is applied to this actuator. The dynamic characteristics are analyzed and measured.

Computed results show that the proposed actuator is able to be independently driven in three directions. However, measured result show that mutual interference is severely observed because of the structure of the mover support mechanism. Therefore, the structure needs to be improved.

The proposed actuator has originality in its structure and operating principle.

This paper aims to propose a new magnetic-geared motor (MGM) which can easily increase the gear ratio up to approximately several hundred. The operational principle is described, and the relationship between the maximum transmission torques of each layer of the differential harmonic magnetic gear is investigated using a mathematical model and finite element method (FEM).

The operational principle and maximum transmission torque are described using a mathematical model. The FEM is used to investigate the operational principle and torque characteristics.

As the proposed model can realize a larger gear ratio than the conventional model, the torque constant can be approximately 100 times as large as that of the conventional model.

The proposed and conventional models have the same shape stator, and it is not optimized.

The relationship between the maximum transmission torques of each layer is described, and this helps the design of a differential type MGM.

Early magnetic-geared motors have a high transmission torque density. However, the torque due to the coil is low because the permanent magnets in the stator become a large magnetic resistance when the current is applied to the coil. The purpose of this paper is to propose magnetic-geared motors which have a high transmission torque density and torque due to the coil. In addition, the proposed magnetic-geared motors are compared with past magnetic-geared motors and the effectiveness is verified by using finite element analysis.

A new magnetic-geared motor which has permanent magnets in the stator slot are proposed. The torque due to the coil increases by removing permanent magnets at the tip of the stator of past magnetic-geared motors. The permanent magnets placed in the stator slots are all magnetized to the outward direction and then the stator teeth are all magnetized to the inward direction. The maximum transmission torque and torque constant are compared.

The proposed magnetic-geared motor has a slightly smaller maximum transmission torque than the early magnetic-geared motors. However, the maximum transmission torque of the proposed magnetic-geared motor is high enough for practical uses. The torque due to the coils is higher than the early magnetic-geared motors.

The proposed magnetic-geared motor has originalities in its structure, especially in the permanent magnets in the stator slots.

The purpose of this paper is to propose a new electromagnetic spherical actuator with three‐degree‐of‐freedom. Multi‐degree‐of‐freedom actuators which can be operated in arbitrary axis come to attract attention because of the solution for efficiency, weight, size, and so on. Particularly, spherical actuators are studied as the application to the joints and eyeballs for robots because they can be freely rotated in every axis direction.

The paper proposes a new electromagnetic spherical actuator with three‐degree‐of‐freedom in rotation, and the torque characteristics of the actuator are computed by the 3D finite element method (FEM). The validity of the computation is confirmed through the measurement of a prototype.

It is found that this actuator realized the high torque of more than 1.0 Nm in every axis circumference.

A new spherical three‐degree‐of‐freedom actuator is proposed. The torque characteristics of the improved model are calculated employing the 3D FEM. The validity of the analysis is verified through the comparison with the measured results of the prototype. Furthermore, the improved model is proposed to increase the torque, and the effectiveness of the model is confirmed.

The purpose of this paper is to propose an analysis method of negative ion by electrostatic atomization. Because the electrostatic atomization includes large deformation of a drop of water, it is difficult to analyze with conventional fluid analysis methods such as the finite differences method, the finite element method (FEM) and so on.

In this method, electrostatic field equation is coupled with Navier‐Stokes equation of a drop of water, employing the moving particle semi‐implicit method and FEM. The validity of the method is verified through the measurement.

It was found that the difference between calculated and measured results becomes large as the voltage increases.

In order to improve the accuracy, it is necessary to improve the way to calculate surface tension and the analysis condition.

This paper confirms the usefulness of the numerical method to elucidate electrostatic atomization.

This paper aims to describe the simulation technique which can be used at the design stage in order to efficiently develop low‐electromagnetic emission type lighting implements.

The influence on the conducted noise by the change of the implements' shape is investigated employing the 3D finite element method. Because of the difficulty in modelizing the electronic ballast accurately as a noise source, the electronic ballast is replaced by a comparison spectrum transmitter. Line impedance stabilization network is used for the measurement of the noise. The validity of this numerical model is confirmed by comparing the measurement results.

The validity of the computation was confirmed by comparison with the measured results of a simplified implement model. The difference between the measured and calculated results was less than 5 dB all over the frequency range.

The frequency range is from 10 to 30 MHz and the construction and wiring of the implement have a great influence on the electromagnetic field.

In previous papers, circuit simulators are used to analyze conducted emission from an electronic circuit including inverter, where common mode current cannot be taken into consideration. Therefore, the displacement current was taken into consideration in the model. Not only the implement, but also the measurement method and environment are modelized in the analyzed model.

The purpose of this paper is to develop a dynamic analysis method of a novel spherical resonant actuator. In this method, the magnetic field equation is coupled with the electric circuit equation and the motion equation with the mesh modification method using the Laplace equation applied to the rotation of the spherical actuator.

The static torque characteristics and dynamic characteristics of the spherical resonant actuator using the proposed method are clarified. The calculated results are compared with the measured ones.

The calculated static torque agrees well with the measured one. The validity of the computation using the proposed method is quantitatively clarified through the comparison with the measurement.

The paper proposes the dynamic analysis method of the complicated spherical resonant actuator using the mesh modification method by the Laplace equation.

The purpose of this paper is to propose a magnetic‐geared motor with permanent magnets only on the high‐speed rotor as a solution to the problems of magnetic gears. Magnetic gears have some advantages such as no mechanical loss and maintenance‐free operation that are not observed in conventional mechanical gears. Furthermore, they have inherent overload protection. A novel structure which the magnetic gear is integrated with the brushless motor (magnetic‐geared motor) was proposed by Atallah et al. This magnetic‐geared motor is based on the magnetic gear which consists of a high‐ and low‐speed rotor, and a stator. Although this magnetic‐geared motor has a high‐torque density, problems with manufacturing and cost exist because multi‐pole permanent magnets are mounted on the high‐speed rotor and stator.

A magnetic‐geared motor with permanent magnets only on the high‐speed rotor was proposed and its operational principle was described. The cogging torque characteristics were mathematically formulated and the authors ascertained that the cogging torque contains components of multiples of 60th order. In order to verify the order of the cogging torque, the 3‐D finite element method analysis was conducted and measurements on a prototype were carried out.

The 60th component and its multiples were observed in the computed and measured cogging torque waveform. However, the cogging torque characteristics, especially the order of the cogging torque on the low‐speed rotor, have not been clarified.

In the near future, cogging torque reduction methods will be proposed, and verified by conducting 3‐D FEM analyses and carrying out measurements on a prototype. Furthermore, the torque characteristics when an electrical current is applied to the coils and the eddy‐current loss characteristics will be verified.