A permanent magnet elastomer is a magnetized elastomer in which particles of a hard magnetic material such as neodymium particles are dispersed. The permanent magnet elastomer reacts against an applied magnetic field. In this study, sound absorption properties of a permanent magnet elastomer membrane were investigated experimentally by using an acoustic tube which can be able to apply magnetic field. The permanent magnet elastomer membrane is deformed by applied magnetic field and the sound absorption properties can be controlled by changing the direction of applied magnetic field.

Flexible steel plates are used in the manufacturing process of household electrical products. Since flexible steel plates are transported by rollers, surface deterioration of the plates is problem. One method to solve this problem is non-contact gripping and conveyance using magnetic levitation technology. The proposed magnetic levitation method is a two-degree-of-freedom active control system that controls vertical and horizontal motion. In this study, experiments were conducted under different steady current using the control system.

The optically pumped magnetometer (OPM) is one of the most sensitive magnetic field sensors, which is widely used for ultra-weak magnetic field measurement. To localize and quantify the magnetic source, array OPMs are needed to work simultaneously in a small area. However, an OPM typically employs a modulation magnetic field. In the presence of multiple sensors, the modulation fields of the OPMs interference with each other, resulting in reduced measurement accuracy and sensitivity. This paper proposes a novel array OPMs setting to eliminate the mutual interference of the modulation magnetic field, where the OPMs are modulated by a specially designed coil. The coil is optimized based on the numerical calculation and it generates an almost uniform magnetic field in the sensor area. The operating principle of the method is analyzed by solving the Bloch equation. Then, the feasibility of the method is demonstrated experimentally with compact OPMs and the magnetocardiography signal of human body is measured.

Flexible steel plates have problems with the transport method. Flexible steel plates are transported by rollers. However, the contact between the roller and steel plate degrades the surface quality. To solve this problem, non-contact transportation for steel plates using electromagnetic force has been proposed. In this study, a magnetic levitation system that suppresses deflection using gravity. In this report, the characteristics of the system under vertical disturbance were investigated.

This work introduces a novel electromagnetic active vibration isolator that employs a displacement amplification mechanism and fuzzy PID control. The integration of a ring-shaped permanent magnet and an electromagnetic coil within the central part of the rhombic displacement amplification mechanism leads to a substantial enhancement in the electromagnetic force stroke. Consequently, the effectiveness of vibration isolation is significantly improved. Firstly, the vibration isolation principle of the isolator is presented. Subsequently, a multi-node theoretical model is developed for the vibration isolator. Finally, the vibration isolation performance of the isolator is simulated and analyzed using fuzzy PID control.

The optical loads on high-resolution satellites are very sensitive to vibration. Therefore, it is crucial to meet the pointing accuracy and micro-vibration suppression for the optical loads. In this work, a parallel platform with new nine legs is designed for integrated micro-vibration and pointing control. The legs include three voice coil and six piezoelelctric actuators. Combining the decoupling of micro-vibration and attitude motion, a joint control model is built in Matlab/Simulink. The simulation result shows that the new platform can achieve good performance in both micro-vibration suppression and precision pointing control.

In the centrifuge shaking table composite environmental test system, the centrifuge arm is a typical beam-like structure. When regarded as a rigid body, the dynamic characteristics of the composite system cannot be accurately reflected. An original finite volume approach is used to model the centrifuge arm, along with a multi-rigid body model of the shaking table. Simulation results show non-negligible coupling of the composite system.

This paper proposes a noise level calculation formula based on vibration velocity from the mechanism of bridge arm reactor noise generation. The evaluation method first calculates the equivalent flux density value. Then, the deformation displacement is solved according to the mechanical relationship of the thin-walled ring and the vibration velocity sum of the multilayer encapsulations is obtained from the displacement to time derivative. The noise level is calculated by the sound pressure level equation, and the error is 6.1% when comparing the sound level measurement test results. Finally, the sensitivity calculation of the analytical formula is performed to obtain the influence of structural and material parameters on the sound pressure level.

The evolution of aerodynamic devices has improved the performance of competition vehicles.On the other hand, suspension systems have become stiffer to maintain a constant distance between the vehicle body and the road surface in order to maximise the performance of aerodynamic devices. Stiffer suspensions tend to reduce the static displacement of the vehicle spring against aerodynamic forces, while ground load fluctuations tend to increase. Therefore, a basic study of two methods was conducted to develop an active suspension system that optimises aerodynamic performance and load fluctuations to improve vehicle dynamics: simulation and a vibration test system that verifies the dynamic behaviour of a scale car by vibrating it.

Deformation and vibration of thin-walled structures exist simultaneously under fast maneuvering environment, which affects the accuracy and safety of structures seriously. In this paper, the plate’s dynamic control equation under time-varying environment is established, which includes four coupling factors: rigid body motion coupling, deformation coupling，rigid body motion and deformation coupling, electromechanical coupling. MFC actuator and sliding mode control algorithm are employed to control the elastic deformation and vibration of the plate induced by the time-varying motion. The results show that dynamic model established and control strategy optimized can be used for deformation and vibration control of plate undergoing overall motion with 6 degrees of freedom effectively.

In thin steel sheet production lines, contact conveying by rollers is used, which sometimes results in scratches and plating defects on the steel sheet surface. To solve this problem, non-contact conveyance by magnetic levitation is expected. When thin steel plates are magnetically levitated, magnetic levitation control becomes difficult due to deflection caused by the flexibility of the plate. Therefore, we have proposed a curved magnetic levitation system that improves the levitation stability by curving the steel plate for magnetic levitation. However, the dynamic behavior of thin steel plates during bending magnetic levitation have not been clarified. In this report, we performed a levitation experiments of bending steel plate, and input disturbance to the bending levitation device. From the measured response of levitated and oscillated steel plate, it was confirmed that the bending thin steel plate was in rigid body motion due to the disturbance.

A novel vibration control device based on the piezoelectric shunt damping technology is proposed and successfully applied to a single DOF system. This proposed absorber is composed of a butterfly-shaped steel frame and a piezoelectric stack. This butterfly-shaped structure is designed to protect the piezoelectric stack during the vibration reduction process and maximize the force transmitted to the stack for a better reduction effect. The optimal geometric parameters of the butterfly steel frame are obtained by utilizing the PSO algorithm for structural optimization and parameter analysis. The excellent vibration reduction performance of the optimal-designed absorber is verified by the numerical simulation and experiment.

Ultra-compact mobility has been proposed as a new means of transportation in consideration of short-distance travel and environmental considerations in tourist destinations and urban areas. Since these vehicles are small and lightweight, it is expected that the ride quality will be uncomfortable due to vibration and the driver's discomfort will increase. Therefore, our research group proposes to improve the ride quality by mounting the active seat suspension on the seat. In this study, we conducted a basic study on ride comfort estimation considering the psychological state.

The sustainability of Information and Communication Technologies (ICT) is discussed in a thermodynamic framework regarding the end of Moore's and Koomey's laws and in a context of data deluge. Magnetism is expected to provide a few orders of magnitude for the efficiency of ICT towards the thermodynamic maturity.