Electromechanical Coupling Characteristics Research Articles

Torsional vibration suppression and electromechanical coupling characteristics of electric drive system considering misalignment

Torsional vibration suppression and electromechanical coupling characteristics of electric drive system considering misalignment

Flexible BTO piezoelectric generator fabricated by hydrothermal method with the assistance of lignocellulose and carbon nanomaterials

Flexible BTO piezoelectric generator fabricated by hydrothermal method with the assistance of lignocellulose and carbon nanomaterials

Electromechanical Coupling Characteristics of Functionally Graded Piezoelectric Ceramic Beam

Electromechanical Coupling Characteristics of Functionally Graded Piezoelectric Ceramic Beam

Dynamic characteristics of electromechanical coupling of body-suspended drive system for high-speed trains under wheel polygonal wear

Wheel polygonal wear can trigger intense wheel–rail interactions in railway vehicles, posing a significant threat to traffic safety. However, the mechanism and interaction of the influence of wheel polygonal wear on the electromechanical coupling characteristics of high-speed trains remain unclear. Therefore, this paper proposes a joint simulation modelling method that takes into account the integration of the electrical subsystem with the complete mechanical subsystem. A comprehensive analysis is conducted on the dynamic response of the high-speed train’s body-suspended drive system under a wide range of frequency excitations arising from harmonic torque, gear meshing, and wheel polygon wear. The results indicate that the electrical system generates a substantial amount of harmonic frequency components, resulting in a significant increase in the vibration of the train. The wheel polygon wear causes a broadening of the low-frequency resonance band, revealing a relatively prominent observation interval for the dynamic characteristics. Concurrently, it is discovered that the 23rd-order wheel polygon wear excites the system’s resonance frequency, and as the wavelength of the wheel polygon increases, the acceleration vibrations intensify progressively. Research reveals first the interaction of electrical system and mechanical system under wheel polygon wear, especially in the resonance gain characteristics under polygons and harmonic torques.

Rare-earth praseodymium-substituted Bi5Ti3FeO15 exhibiting enhanced piezoelectric properties for high-temperature application

Rare-earth praseodymium-substituted Bi5Ti3FeO15 exhibiting enhanced piezoelectric properties for high-temperature application

Electromechanical coupling characteristics of multilayered piezoelectric quasicrystal plates in an elastic medium

AbstractQuasicrystals (QCs) have attracted tremendous attention of researchers for their unusual properties. In this paper, an exact electric‐elastic solution of the simply supported and multilayered three‐dimensional (3D) cubic piezoelectric quasicrystal (PQC) nanoplate with the nonlocal effect is derived. Based on the basic elasticity equation of 3D QCs, we construct the linear eigenvalue system in terms of the pseudo‐Stroh formalism, from which the general solutions of the extended displacements and stresses in any homogeneous layer can be obtained. The two‐parameter foundation model is utilized to simulate the interaction between the nanoplate and elastic medium. The propagator matrices are employed to connect the field variables at the upper interface to those at the lower interface of each layer. Based on the boundary conditions of the upper and lower surfaces of the laminate and foundation model, the solutions are employed to derive from the global propagator matrix. Compared with the conventional propagator matrix method, a new propagator method is reestablished to deal with numerical instabilities of the case of large aspect ratio and high‐order frequencies for QC laminates. Finally, typical numerical examples are presented to illustrate the influence of nonlocal parameters and elastic medium coefficients on phonon, phason, and electric variables of 3D PQC nanoplates.

Evaluating head impact intensities and accelerations using flexible wearable sensors for traumatic brain injury assessment

Evaluating head impact intensities and accelerations using flexible wearable sensors for traumatic brain injury assessment

Actuation strategy characterizations of a vibro-impact crawling robot driven by dielectric elastomer actuators

Vibro-impact crawling robots driven by the emerging dielectric elastomer actuators (DEAs) feature the advantages of reduced system complexity and bidirectional locomotion capability. However, due to the lack of systematic dynamic models and in-depth investigations, the fundamental locomotion principles of the robots are still unclear and therefore their applications in real-world scenarios remain hindered. In this paper, a comprehensive dynamic model of this robot is developed by considering the complex interactions between the electro-mechanical coupling, impact mechanism, and multiple nonlinear friction characteristics. By incorporating extensive modeling and experimental studies, we explain the fundamental principles that lead to the bidirectional locomotion of the robot. The actuation strategies for both forward and backward locomotion are characterized in-depth, which include the actuation frequencies, relative phases, and waveforms. Three typical contact surface cases (i.e. rigid & dry, rigid & viscous, compliant & viscous) are considered in this paper, where we report the changes in the optimal actuation strategies for bidirectional locomotion with the contact surfaces and reveal the influences of key factors of friction coefficient, viscosity, and material compliance. The key findings reported in this work can build foundations for developing a highly robust and efficient DEA-driven vibro-impact crawling robot for broad applications.

An improved equivalent circuit model of a V-shape single-mode linear ultrasonic motor with new actuation mode

An improved equivalent circuit model of a V-shape single-mode linear ultrasonic motor with new actuation mode

Design and Analysis of Porous Elastomeric Polymer Based on Electro-Mechanical Coupling Characteristics for Flexible Pressure Sensor.

Elastomeric polymers have gained significant attention in the field of flexible electronics. The investigation of the electro-mechanical response relationship between polymer structure and flexible electronics is in increasing demand. This study investigated the factors that affect the performance of flexible capacitive pressure sensors using the finite element method (FEM). The sensor employed a porous elastomeric polymer as the dielectric layer. The results indicate that the sensor's performance was influenced by both the structural and material characteristics of the porous elastomeric polymer. In terms of structural characteristics, porosity was the primary factor influencing the performance of sensors. At a porosity of 76%, the sensitivity was 42 times higher than at a porosity of 1%. In terms of material properties, Young's modulus played a crucial role in influencing the performance of the sensors. In particular, the influence on the sensor became more pronounced when Young's modulus was less than 1 MPa. Furthermore, porous polydimethylsiloxane (PDMS) with porosities of 34%, 47%, 67%, and 72% was fabricated as the dielectric layer for the sensor using the thermal expansion microsphere method, followed by sensing capability testing. The results indicate that the sensor's sensitivity was noticeably influenced within the high porosity range, aligning with the trend observed in the simulation.

Dynamics modeling and electromechanical coupling characteristics analysis of cage induction motors

Dynamics modeling and electromechanical coupling characteristics analysis of cage induction motors

A hybrid energy harvester inspired by bionic flapping wing structure based on magnetic levitation.

A hybrid energy harvester based on magnetic levitation is inspired by the structure of the flapping wing, which consists of two parts: one is a flapping wing structure mounted with a piezoelectric sheet, which can achieve piezoelectric energy harvesting; the other is an intermediate muscle unit, which is vertically arranged by three groups of permanent magnets to achieve magnetic levitation electromagnetic energy harvesting. An electromechanical-electromagnetic coupling model of this harvester is established based on electromechanical coupling characteristics. The simulation analysis can evaluate the magnetic field distribution and nonlinear magnetic properties and also analyze its effects on the output performance. Several experiments are designed to verify the effectiveness of the hybrid energy harvesting structure and to check the influence of the number of magnets on the output power. The maximum output power of the proposed structure can generate 13.61 mW at 4.5Hz excitation.

Electromechanical coupling characteristics analysis of vertical stirred mill based on ECS-MBD-DEM

Electromechanical coupling characteristics analysis of vertical stirred mill based on ECS-MBD-DEM

Electromechanical analysis of a piezoelectric semiconductor bilayer system with imperfect interface

Electromechanical analysis of a piezoelectric semiconductor bilayer system with imperfect interface

A piezoelectric–electromagnetic hybrid energy harvester inspired by flapping motion of the Diptera insect

Low-frequency vibration is widespread in nature. Vibration energy harvesting is considered to be a reliable and sustainable method to achieve continuous power supply. It is a feasible method to design an energy harvesting system of the bio-inspired mechanical structure to improve the efficiency of energy harvesting. A hybrid energy harvester piezoelectric–electromagnetic that mimics the flapping wing motion of the Diptera insect. The biomimetic energy harvesting device consists of two piezoelectric cantilever beams structure with the mass block installed, which mimics the flapping movement mechanism of the Diptera insect. The intermediate part of this harvester inspired by the insect skeleton and muscle structure of the Diptera insect is composed of magnetic levitation coupled repulsion structure, which is easily affected by vibration and changes greatly, to realize electromagnetic energy harvesting. The ‘click’ mechanism of the Diptera insect is constructed by storing energy in springs to improve the performance of energy harvesting devices. The hybrid energy harvesting device realizes piezoelectric–electromagnetic energy harvesting with multiple energy outputs at one excitation input. A dynamic model of the proposed energy harvester is constructed based on the electromechanical coupling characteristics. The modal analysis and structure optimization of this device is realized by the finite element method (FEM). The FEM simulation and experimental results can verify that under the low-frequency excitation of 3 Hz, the maximum output power of the designed harvester reaches 12.33 mW in the low-frequency environment.

Dynamic modeling and analysis of a vibration-driven robot driven by a conical dielectric elastomer actuator

This article aims to establish a theoretical model of a vibration-driven robot driven by a conical dielectric elastomer actuator and analyze its characteristics, in order to make up for the lack of theoretical model construction and parameter evolution analysis for this type of robot. This article introduces a vibration-driven robot driven by a conical dielectric elastomer actuator, and then establishes its dynamic model based on its electromechanical coupling and viscoelastic characteristics. Subsequently, simulation research is conducted using this model. Overall, this article derived a dynamic equation that can be applied to this type of robot, analyzed its motion characteristics, studied the effects of different parameters on it, and discussed the influence of viscoelasticity on vibration-driven robots. The proposed dynamic model and evolution law of vibration robots can provide theoretical guidance for subsequent control and optimization.

Electromechanical dynamic analysis for powertrain of off-grid switched-reluctance wind turbine hydrogen production system

Electromechanical dynamic analysis for powertrain of off-grid switched-reluctance wind turbine hydrogen production system

Analysis of electromechanical coupling characteristics of electrics vehicle electric drive system considering current harmonic excitation

In order to study the electromechanical coupling dynamics characteristics of the drive motor and gear transmission system in the electric vehicle electric drive system, firstly, an electromechanical coupling dynamics model of the electric vehicle electric drive system is established; the electromechanical coupling vibration characteristics of the electric drive system under current harmonic excitation is compared and analyzed. The influence law of permanent magnet synchronous motor current harmonics on the meshing vibration of gear transmission system is revealed. The simulation results show that there is an obvious electromechanical coupling effect in the electric drive system; the harmonics of the drive motor can aggravate seriously the vibration state of the mechanical drive system; the research results provide a theoretical reference for further research on the vibration source positioning and active vibration reduction control strategy for the electric drive system of electric vehicles.

Bionic flutter wing piezoelectric-electromagnetic composite energy harvesting system

The bionic structure has great potential in the field of energy harvesting. Inspired by the fluttering structure of dipteran insects, this paper proposes a novel bionic multi-domain energy harvester based on the mechanism of fluttering behavior of dipteran insects. The device is designed concerning the skeletal and muscular structures of dipteran insects, using a flexible cantilever beam and a rigid linkage to simulate the fluttering wings and skeletal structures of dipteran insects, while the reciprocating motion generated by the central permanent magnet with the cooperation of gravity and a limiting spring simulates the muscle contraction of dipteran insects. In the process of simulating the fluttering motion, the piezoelectric sheet installed on the cantilever beam can harvest the vibration energy, while the magnetic induction coil arranged on the outside of the central permanent magnet can harvest the electromagnetic energy generated by the vertical reciprocating motion, providing a second channel of energy harvesting for the bionic fluttering wing piezoelectric-electromagnetic composite energy harvesting (BCEH) system. Based on the electromechanical coupling characteristics of the energy harvesting device, a centralized parametric dynamics model of the system is established. The modal analysis of the bionic structure is carried out by using the finite element method, and the natural frequency and mode shape of the structure are determined. The key structural parameters are optimized through theoretical calculation and simulation. After optimization, the output voltage and output power of the proposed energy harvester have been effectively improved. The output voltage of the piezoelectric port has been increased by up to 347%, and the output power has been increased by up to 1789%. The output voltage of the electromagnetic port has been increased by up to 40%. The output power has been increased by up to 137%. So the experimental results show that the bionic flapping-wing composite energy harvesting system can achieve better energy harvesting.

Research on mechanical resonance of Precise cable drive systems

Precise cable drive is a light, concise and efficient spatial friction flexible transmission mode, which has the characteristics of flexible layout, lightweight and miniaturization. It is a good choice for Acquiring tracking and pointing applications (ATPs). But the cable drive mechanism (CDM) is easy to cause large-scale speed oscillation in the process of performing tasks as cable compliance. This paper focused on the mechanical resonance in a practical full-closed loop positioning control system. A dynamic model with the electro-mechanical and rigid-flexible coupling characteristics is proposed, which is capable to analyze the global influence factors on speed oscillation. The parametric sensitivities have been conducted to investigate the effects of design parameters on mechanical resonance.