scholarly journals The Static and Dynamic Sensitivity of Magnetostrictive Bioinspired Whisker Sensor

2018 ◽  
Vol 2018 ◽  
pp. 1-6 ◽  
Author(s):  
Ran Zhao ◽  
Qingjie Yuan ◽  
Jianwu Yan ◽  
Qanguo Lu
Keyword(s):  
Natural Frequency ◽  
Cantilever Beam ◽  
Vibration Frequency ◽  
Experimental System ◽  
High Sensitivity ◽  
First Order ◽  
Dynamic Sensitivity ◽  
Flow Sensing ◽  
Technical Indicator ◽  
Static Sensitivity

Magnetostrictive bioinspired whisker is a new kind of sensor that can realize tactile and flow sensing by utilizing magnetoelastic effect. The sensitivity is a key technical indicator of whisker sensor. The paper presented a new magnetostrictive whisker based on Galfenol cantilever beam, as well as its operation principle. Then, the static and dynamic sensitivity of the whisker sensor was investigated by using a self-made experimental system. The results illustrated that the proposed sensor has a high sensitivity. Its static sensitivity is 2.2 mV/mN. However, its dynamic sensitivity depends on the vibration frequency. When working at the natural frequency of the cantilever beam, the dynamic sensitivity performs an obvious increase—1.3 mV/mN at 3.5 Hz (the first-order natural frequency) and 2.1 mV/mN at 40 Hz (the second-order natural frequency), respectively.

Analysis on the Effect of Bend Curve Radius to Inherent Characteristics of the U-Tubes

2012 ◽  
Vol 490-495 ◽  
pp. 355-359
Author(s):  
Li Na Zhang ◽  
Zhen Yu Ma ◽  
Min Shan Liu
Keyword(s):  
Heat Transfer ◽  
Numerical Simulation ◽  
Resonance Frequency ◽  
Natural Frequency ◽  
Vibration Frequency ◽  
Bend Radius ◽  
First Order ◽  
Transfer Tube ◽  
Shaped Tube ◽  
Curve Radius

For large-capacity steam generator, piping zone diameter of U-tube section is nearly 5m, the range of U-shaped bend radius is very large from Zero meters to 2.5 meters, this affects obviously the Vibration characteristics of heat transfer tube, this effect is researched using numerical simulation. Engineering formulas of natural frequency of U-shaped tube under different conditions are given. According the vibration-type, The lowest natural frequency of U-shaped tube is plane vibration frequency of the first order for adding one anti-vibration bar or not. Natural frequency of U-shaped tube increases significantly adding anti-vibration bars to bend, which is favorable to avoid the resonance frequency and severe vibration of U-shaped tube

Vibration Frequency Analytical Formula and Parameter Sensitivity Analysis for Rocking Mass Gyroscope

2011 ◽  
Vol 317-319 ◽  
pp. 1068-1073 ◽  
Author(s):  
Xiong Wang ◽  
Ding Bang Xiao ◽  
Xue Zhong Wu ◽  
Sheng Yi Li
Keyword(s):  
Sensitivity Analysis ◽  
Natural Frequency ◽  
Vibration Frequency ◽  
Optimization Design ◽  
Analytical Formula ◽  
High Sensitivity ◽  
Parameter Sensitivity Analysis ◽  
Fem Simulations ◽  
Operational Modes ◽  
Modal Method

Rocking-Mass Gyroscope (RMG) is a dual-axial symmetry vibrating mass gyroscope, whose operational modes are completely uniform, and values of frequency are equal. RMG has the potential to be the gyroscope with high sensitivity. Predicting the frequencies for the operational modes of RMG is critical. The natural frequency analytical formula of RMG is developed by using the assumed modal method and vector composition method. The FEM simulations and experiments validate the analytical formula. The sensitivities of natural frequency to different parameters are also analyzed. The presented results provide references for optimization design of RMG.

The Analysis on the First Order Vibration Frequency of Post-Tensioned Unbonded Pre-Stress Concrete Beam

2011 ◽  
Vol 105-107 ◽  
pp. 107-111
Author(s):  
Jin Bo Ma ◽  
Li Jun Wang ◽  
Ting Tang
Keyword(s):  
Natural Frequency ◽  
Vibration Frequency ◽  
Linear Correlation ◽  
Vibrational Frequency ◽  
Concrete Beam ◽  
Experimental Results ◽  
Structural Vibration ◽  
First Order ◽  
Post Tensioned

In order to study the influence on structural vibration from pre-stress and eccentricity, a experiment is designed. After analyzing the experimental results of 9 groups of modal tests on a post-tensioned unbonded pre-stress concrete beam, the following conclusions can be drawn: The influences on first order vibration frequency which are caused by eccentricity and pre-stress really exist. The rules of influences brought about by eccentricity and pre-stress on first order vibration frequency are complicated. When the eccentricity is close to the centroid, the linear correlation between the pre-stress and the first natural frequency will be good, on the contrary, the nonlinear will be strengthened. The first order vibrational frequency of the tested beam will go up with the increase of pre-stress.

scholarly journals Effect of Potential Energy Variation on the Natural Frequency of an Euler–Bernoulli Cantilever Beam Under Lateral Force and Compression

2017 ◽  
Vol 84 (5) ◽  
Author(s):  
B. Béri ◽  
G. Stépán ◽  
S. J. Hogan
Keyword(s):  
Potential Energy ◽  
Theoretical Result ◽  
Natural Frequency ◽  
Cantilever Beam ◽  
Vibration Frequency ◽  
Lateral Force ◽  
Bending Vibration ◽  
Energy Variation ◽  
Frequency Calculation

A cantilever beam is subjected to both lateral force and compression under gravity. By taking into account the potential energy variation of the system, we develop a theoretical result that greatly simplifies the bending vibration frequency calculation in agreement with the experiments.

Reduced Order Model of MEMS Sensors Near Natural Frequency

2011 ◽  
Author(s):  
Dumitru I. Caruntu ◽  
Jose C. Solis Silva
Keyword(s):  
Natural Frequency ◽  
Nonlinear Response ◽  
Casimir Effect ◽  
Electrostatic Force ◽  
Reduced Order Model ◽  
Mass Detection ◽  
Order Model ◽  
Reduced Order ◽  
First Order ◽  
Electrostatically Actuated

The nonlinear response of an electrostatically actuated cantilever beam microresonator sensor for mass detection is investigated. The excitation is near the natural frequency. A first order fringe correction of the electrostatic force, viscous damping, and Casimir effect are included in the model. The dynamics of the resonator is investigated using the Reduced Order Model (ROM) method, based on Galerkin procedure. Steady-state motions are found. Numerical results for uniform microresonators with mass deposition and without are reported.

scholarly journals Real-Time and In-Flow Sensing Using a High Sensitivity Porous Silicon Microcavity-Based Sensor

Sensors ◽  
2017 ◽  
Vol 17 (12) ◽  
pp. 2813 ◽  
Author(s):  
Raffaele Caroselli ◽  
David Martín Sánchez ◽  
Salvador Ponce Alcántara ◽  
Francisco Prats Quilez ◽  
Luis Torrijos Morán ◽  
...  
Keyword(s):  
Porous Silicon ◽  
Real Time ◽  
High Sensitivity ◽  
Flow Sensing

scholarly journals Influence of Frequency on the Resolution of Magnetostrictive Bio-Inspired Whisker Sensors

2018 ◽  
Vol 2018 ◽  
pp. 1-7
Author(s):  
Ran Zhao ◽  
Bo-wen Wang ◽  
Quan-guo Lu ◽  
Jian-wu Yan ◽  
Xiao-cui Yuan
Keyword(s):  
Vibration Frequency ◽  
Dynamic Testing ◽  
Theoretical Calculations ◽  
Beam Theory ◽  
Experimental System ◽  
Flow Sensors ◽  
Maximum Resolution ◽  
Sensing Model ◽  
Euler Bernoulli Beam ◽  
Good Agreement

Magnetostrictive biomimetic whiskers have been used as tactile and flow sensors. Compared to other types of whiskers, such whiskers have the advantage of being able to perform static and dynamic measurements. For dynamic measurement, the whisker’s resolution changes with varying vibration frequency; however, the mechanism for this influence has not been studied yet. Thus, the aim of this study is to investigate the resolution–frequency correlation. First, the structure and operation principle of the whisker were analyzed. Then, the Euler–Bernoulli beam theory was employed to establish the sensing model of the magnetostrictive whisker. Finally, the mapping relationship between sensor resolution and frequency was obtained. The eigenfrequency analysis was implemented by FEM to obtain the frequency response of the whisker. A vibration experimental system was built for dynamic testing. The experimental results were in good agreement with the theoretical calculations. Furthermore, it was noted that the resolution was positively correlated with frequency, and the maximum resolution was attained at the natural frequency (two peak values appeared at the first-order and second-order eigenfrequencies). Our research reveals the manner in which a whisker sensor’s resolution is affected by the vibration frequency. The theoretical model can be used to predict the resolution of magnetostrictive whisker sensors.

scholarly journals Three-Dimensional Trajectory Construction and Observation of Group Behavior of Wild Bats During Cave Emergence

2021 ◽  
Vol 33 (3) ◽  
pp. 556-563
Author(s):  
Emyo Fujioka ◽  
Mika Fukushiro ◽  
Kazusa Ushio ◽  
Kyosuke Kohyama ◽  
Hitoshi Habe ◽  
...  
Keyword(s):  
Quantitative Estimation ◽  
Three Dimensional ◽  
Experimental System ◽  
High Sensitivity ◽  
Group Behavior ◽  
Three Dimensions ◽  
Detection And Tracking ◽  
External Objects ◽  
Behavioral Classification

Echolocating bats perceive the surrounding environment by processing echoes of their ultrasound emissions. Echolocation enables bats to avoid colliding with external objects in complete darkness. In this study, we sought to develop a method for measuring the collective behavior of echolocating bats (Miniopterus fuliginosus) emerging from their roost cave using high-sensitivity stereo-camera recording. First, we developed an experimental system to reconstruct the three-dimensional (3D) flight trajectories of bats emerging from the roost for nightly foraging. Next, we developed a method to automatically track the 3D flight paths of individual bats so that quantitative estimation of the population in proportion to the behavioral classification could be conducted. Because the classification of behavior and the estimation of population size are ecologically important indices, the method established in this study will enable quantitative investigation of how individual bats efficiently leave the roost while avoiding colliding with each other during group movement and how the group behavior of bats changes according to weather and environmental conditions. Such high-precision detection and tracking will contribute to the elucidation of the algorithm of group behavior control in creatures that move in groups together in three dimensions, such as birds.

scholarly journals Design optimization of vehicle asynchronous motors based on fractional harmonic response analysis

2021 ◽  
Vol 12 (1) ◽  
pp. 689-700
Author(s):  
Ao Lei ◽  
Chuan-Xue Song ◽  
Yu-Long Lei ◽  
Yao Fu
Keyword(s):  
Finite Element ◽  
Finite Element Model ◽  
Natural Frequency ◽  
Asynchronous Motor ◽  
Element Model ◽  
Design Parameters ◽  
Response Analysis ◽  
Harmonic Response ◽  
First Order ◽  
Harmonic Response Analysis

Abstract. To make vehicles more reliable and efficient, many researchers have tried to improve the rotor performance. Although certain achievements have been made, the previous finite element model did not reflect the historical process of the motor rotor well, and the rigidity and mass in rotor optimization are less discussed together. This paper firstly introduces fractional order into a finite element model to conduct the harmonic response analysis. Then, we propose an optimal design framework of a rotor. In the framework, objective functions of rigidity and mass are defined, and the relationship between high rigidity and the first-order frequency is discussed. In order to find the optimal values, an accelerated optimization method based on response surface (ARSO) is proposed to find the suitable design parameters of rigidity and mass. Because the higher rigidity can be transformed into the first-order natural frequency by objective function, this paper analyzes the first-order frequency and mass of a motor rotor in the experiment. The results proved that not only is the fractional model effective, but also the ARSO can optimize the rotor structure. The first-order natural frequency of asynchronous motor rotor is increased by 11.2 %, and the mass is reduced by 13.8 %, which can realize high stiffness and light mass of asynchronous motor rotors.

Dynamic Analysis of Elastic Beam-Like Mechanism Systems

1989 ◽  
Vol 111 (4) ◽  
pp. 626-629
Author(s):  
W. Ying ◽  
R. L. Huston
Keyword(s):  
Dynamic Analysis ◽  
Dynamic Behavior ◽  
Cantilever Beam ◽  
Equations Of Motion ◽  
Elastic Beam ◽  
Order Perturbation ◽  
First Order ◽  
Geometric Stiffness ◽  
Stiffness Matrices ◽  
First Order Perturbation

In this paper the dynamic behavior of beam-like mechanism systems is investigated. The elastic beam is modeled by finite rigid segments connected by joint springs and dampers. The equations of motion are derived using Kane’s equations. The nonlinear terms are linearized by first order perturbation about a system balanced configuration state leading to geometric stiffness matrices. A simple numerical example of a rotating cantilever beam is presented.

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