scholarly journals Piezoelectric Ultrasonic Biological Microdissection Device Based on a Novel Flexure Mechanism for Suppressing Vibration

Micromachines ◽  
2021 ◽  
Vol 12 (2) ◽  
pp. 196
Author(s):  
Haibo Huang ◽  
Yifan Pan ◽  
Yan Pang ◽  
Hao Shen ◽  
Xiwei Gao ◽  
...  
Keyword(s):  
Vibration Suppression ◽  
Mouse Tissue ◽  
Design Parameters ◽  
Feed Speed ◽  
Driving Voltage ◽  
Driving Frequency ◽  
Lateral Vibration ◽  
Flexure Mechanism ◽  
Tissue Sections ◽  
Paraffin Tissue

Biological microdissection has a wide range of applications in the field of molecular pathology. The current laser-assisted dissection technology is expensive. As an economical microdissection method, piezoelectric ultrasonic microdissection has broad application prospects. However, the performance of the current piezoelectric ultrasonic microdissection technology is unsatisfactory. This paper aims to solve the problems of the low dissecting precision and excessive wear of the dissecting needle caused by the harmful lateral vibration of the present piezoelectric ultrasonic microdissection device. A piezoelectric ultrasonic microdissection device based on a novel flexure mechanism is proposed. By analyzing the flexure hinge flexibility, the type of flexure beam and the optimal design parameters are determined. Through harmonic response simulation analysis, the newly designed microdissection device with a vibration-suppressing mechanism achieves the best vibration effect when the driving frequency is 28 kHz. Under this driving frequency, the lateral vibration suppression effect is improved by 68% compared to the traditional effect without vibration suppression. Then, based on 3D printing technology, a prototype of a novel microdissection device is produced, and its performance is tested. Experiments on dissecting needle vibration tests show that the flexure mechanism does indeed suppress the lateral vibration of the needle tip. We conducted various tissue dissection experiments on paraffin tissue sections. First, we determine the optimal dissecting parameters (driving voltage, frequency, feed speed, cutting angle) of the new equipment through various parameter dissecting experiments. Then, we adopt these optimal dissecting parameters to perform three kinds of dissecting experiments on mouse tissue paraffin section (liver, lung, bone), dissecting experiments on tissue sections of different thicknesses (3 μm, 4 μm, 5 μm), sampling and extraction experiments on complete tissue. The new device has a better dissecting performance for paraffin tissue sections below a 5 μm thickness and can complete various dissecting tasks. Finally, we compare the wear of the dissecting needles of the new and old devices after the same dissecting tasks. The results prove that the suppression of harmful lateral vibration not only significantly improves the dissecting effect but also increases the service life and durability of the dissecting needle, which is beneficial for reducing the equipment costs.

scholarly journals A Novel Piezoelectric Ultrasonic Biological Micro-Dissection Device Based on Flexure Mechanism for Suppressing Vibration

2020 ◽  
Author(s):  
Haibo Huang ◽  
Yifan Pan ◽  
Yan Pang ◽  
Hao Shen ◽  
Xiwei Gao ◽  
...  
Keyword(s):  
Vibration Suppression ◽  
Simulation Analysis ◽  
Tissue Sample ◽  
Design Parameters ◽  
Driving Frequency ◽  
Lateral Vibration ◽  
Suppression Effect ◽  
Flexure Mechanism ◽  
Vibration Effect ◽  
Wide Range

Biological micro-dissection has a wide range of applications in the field of molecular pathology. The current laser-assisted dissection technology is expensive, and laser radiation can lead to sample contamination. As an economical and pollution-free micro-dissection method, piezoelectric ultrasonic micro-dissection has a wide application prospect. However, the performance of the current piezoelectric ultrasonic micro-dissection technology is unsatisfactory. In this paper, a novel piezoelectric ultrasonic micro-dissection device based on a flexure mechanism is proposed in order to solve the problems of low dissecting precision and excessive wear of the dissecting needle caused by the harmful lateral vibration of the current piezoelectric ultrasonic micro-dissection device. By analyzing the flexibility of flexure hinge, the type of flexure beam and the optimal design parameters are determined. Through comparing the harmonic response simulation analysis of the micro-dissection device based on a flexure mechanism and the traditional micro-dissection device without the flexure mechanism, the newly designed micro-dissection device achieves the best vibration effect when the driving frequency is 28kHz, compared with the traditional micro-dissection device, the lateral vibration suppression effect is improved by 68%. Then, based on the 3D printing technology, a prototype of a novel micro-dissection device was produced, and its performance was tested. It was found that the flexure mechanism did indeed suppress the lateral vibration of the needle tip. Finally, the experiments of 5μm thick paraffin-embedded rat liver sections were carried out, and the effects of different dissecting parameters on the dissecting effect were analyzed, and the optimal dissecting parameters were obtained. By comparing the dissecting effects of the tissue sample and the wear condition of the needle tip between the novel micro-dissection device and the traditional micro-dissection device under their optimal dissecting parameters, it is proved that the suppression of harmful lateral vibration not only significantly improves the dissecting effect, but also improves the service life and durability of the dissecting needle, which is beneficial to reduce the equipment costs.

Analysis of the Application of Piezoelectric Ceramic Material in the De-Icing Technique of the Aircrafts

2017 ◽  
Vol 730 ◽  
pp. 580-586
Author(s):  
Qing Ying Li ◽  
Yong Jiu Zhu
Keyword(s):  
Resonance Frequency ◽  
Ceramic Material ◽  
Piezoelectric Ceramic ◽  
Piezoelectric Ceramics ◽  
Ceramic Materials ◽  
Design Parameters ◽  
Driving Voltage ◽  
Driving Frequency ◽  
Simulation And Experiment ◽  
Design Factors

The application of piezoelectric ceramic material in de-icing technique of aircrafts is presented in numerical simulation and experiment methods. Firstly, the ice properties are introduced briefly as the evaluation of device design. Then, modal simulation of the testing skin of NACA 0030 is performed to determine the position where the piezoelectric ceramics fix. The resonance frequency as the driving frequency in the experiment is calculated in harmonic analysis with the actuators bonding on the testing skin model. Moreover, piezoelectric de-icing rig is fabricated as the modeling results. It is shown that the driving frequency agrees well with the calculated resonance frequency, and the ice can be removed when the driving frequency is 1530 Hz and the driving voltage is 650 V. In addition, design factors as material properties, size of the ceramics, and excitation voltage are discussed. From the numerical calculation, the stress will vary with different piezoelectric ceramic materials and sizes of the ceramics. It will decrease with the increase of thickness of the piezoelectric ceramics, but increase linearly with the increase of the voltage. Therefore it is considerable to choose design parameters for piezoelectric de-icing systems.

Concurrent Vibration Suppression and Energy Harvesting Using Ferrofluids: An Experimental Investigation

2014 ◽  
Author(s):  
Saad F. Alazemi ◽  
Amin Bibo ◽  
Mohammed F. Daqaq
Keyword(s):  
Magnetic Field ◽  
Power Generation ◽  
Energy Harvesting ◽  
Vibration Suppression ◽  
Design Parameters ◽  
Structural Vibrations ◽  
Rectangular Container ◽  
Fluid Damper ◽  
Magnetized Ferrofluid ◽  
Experimental Response

This paper presents an experimental study which examines the design parameters affecting the performance characteristics of a Tuned Magnetic Fluid Damper (TMFD) device designed to concurrently mitigate structural vibrations and harvest vibratory energy. The device which is mounted on a vibrating structure, consists of a rectangular container carrying a magnetized ferrofluid and a pick-up coil wound around the container to enable energy harvesting. Experiments are performed to investigate the three-way interaction between the vibrations of the structure, the sloshing of the fluid, and the harvesting circuit dynamics. In particular, the tuning and optimization is examined for several design parameters including magnetic field spatial distribution and intensity, winding direction, winding location, winding density, and ferrofluid height inside the tank. The experimental response of the device is compared against the conventional TMFD at different excitation levels and frequencies. Results demonstrating the influence of the significant parameters on the relative performance are presented and discussed in terms of vibration suppression and power generation capabilities.

scholarly journals Active Vibration Control of Launch Vehicle on Satellite Using Piezoelectric Stack Actuator

2018 ◽  
Author(s):  
Mehran Makhtoumi
Keyword(s):  
Vibration Control ◽  
Vibration Suppression ◽  
Virtual Work ◽  
Active Vibration Control ◽  
High Strength ◽  
Launch Vehicle ◽  
Design Parameters ◽  
Control Analysis ◽  
Active Vibration ◽  
Piezoelectric Stack Actuator

Satellites are subject to various severe vibration during different phases of flight. The concept of satellite smart adapter is proposed in this study to achieve active vibration control of launch vehicle on satellite. The satellite smart adapter has 18 active struts in which the middle section of each strut is made of piezoelectric stack actuator. Comprehensive conceptual design of the satellite smart adapter is presented to indicate the design parameters, requirements and philosophy applied which are based on the reliability and durability criterions to ensure successful functionality of the proposed system. The coupled electromechanical virtual work equation for the piezoelectric stack actuator in each active strut is drived by applying D'Alembert's principle. Modal analysis is performed to characterize the inherent properties of the smart adapter and extraction of a mathematical model of the system. Active vibration control analysis was conducted using fuzzy logic control with triangular membership functions and acceleration feedback. The control results conclude that the proposed satellite smart adapter configuration which benefits from piezoelectric stack actuator as elements of its 18 active struts has high strength and shows excellent robustness and effectiveness in vibration suppression of launch vehicle on satellite.

scholarly journals Analysis of Generalized Fibrosis in Mouse Tissue Sections with Masson’s Trichrome Staining

BIO-PROTOCOL ◽  
2020 ◽  
Vol 10 (10) ◽  
Author(s):  
Diantha van de Vlekkert ◽  
Eda Machado ◽  
Alessandra d'Azzo
Keyword(s):  
Mouse Tissue ◽  
Tissue Sections

Development of a Latching Valve for Micro-Chem-Lab™

1999 ◽  
Author(s):  
C. Channy Wong ◽  
Douglas R. Adkins ◽  
Ronald P. Manginell ◽  
Gregory C. Frye-Mason ◽  
Peter J. Hesketh ◽  
...  
Keyword(s):  
Power Consumption ◽  
Gas Phase ◽  
Flow Rate ◽  
Integrated System ◽  
Dead Volume ◽  
Design Parameters ◽  
Working Fluid ◽  
Driving Voltage ◽  
Magnetic Actuation ◽  
Phase Detection

Abstract An integrated microsystem to detect traces of chemical agents (μChemLab™) is being developed at Sandia for counter-terrorism and nonproliferation applications. This microsystem has two modes of operation: liquid and gas phase detection. For the gas phase detection, we are integrating these critical components: a preconcentrator for sample collection, a gas chromatographic (GC) separator, a chemically selective flexural plate wave (FPW) array mass detector, and a latching valve onto a single chip. By fabricating these components onto a single integrated system (μChemLab™ on a chip), the advantages of reduced dead volume, lower power consumption, and smaller physical size can be realized. In this paper, the development of a latching valve will be presented. The key design parameters for this latching valve are: a volumetric flow rate of 1 mL/min, a maximum hold-off pressure of 40 kPa (6 psi), a relatively low power, and a fast response time. These requirements have led to the design of a magnetically actuated latching relay diaphragm valve. Magnetic actuation is chosen because it can achieve sufficient force to effectively seal against back pressure and its power consumption is relatively low. The actuation time is rapid, and valve can latch in either an open or closed state. A corrugated parylene membrane is used to separate the working fluid from internal components of the valve. Corrugations in the parylene ensure that the diaphragm presents minimum resistance to the actuator for a relativley large deflection. Two different designs and their performance of the magnetic actuation have been evaluated. The first uses a linear magnetic drive mechanism, and the second uses a relay mechanism. Preliminary results of the valve performance indicates that the required driving voltage is about 10 volts, the measured flow rate is about 50 mL/min, and it can hold off pressure of about 5 psi (34 kPa). Latest modifications of the design show excellent performance improvements.

Improvement on Curve Negotiation Performance of Suspended Monorail Vehicle Considering Flexible Guideway

2020 ◽  
Vol 20 (05) ◽  
pp. 2050057
Author(s):  
Qinglie He ◽  
Chengbiao Cai ◽  
Shengyang Zhu ◽  
Kaiyun Wang ◽  
Yongzhi Jiang ◽  
...  
Keyword(s):  
Interaction Model ◽  
Dynamic Responses ◽  
Secondary Development ◽  
Design Parameters ◽  
Lateral Vibration ◽  
Vibration Level ◽  
Radial Stiffness ◽  
Negotiation Performance ◽  
Lateral Displacements ◽  
Curve Negotiation

This work presents the investigation and improvement on curve negotiation performance of suspended monorail vehicle considering a flexible guideway. First, a spatial train–guideway interaction model of suspended monorail system (SMS) is established based on the secondary development of ANSYS software. Then, the dynamic analysis of the train over the flexible curved guideway is conducted, and the curve negotiation performance of the vehicle and the guideway vibration feature are revealed. Subsequently, several crucial design parameters that significantly influence the curve negotiation performance of the vehicle are found, and their influences on the train–guideway dynamic responses are systematically investigated. Finally, by comprehensively considering the dynamic indexes of the vehicle–guideway system, the optimal ranges of these crucial design parameters are obtained. Results show that decreasing the radial stiffness of guiding tyre can effectively reduce the lateral vibration levels of vehicle and guideway, but it would increase the lateral displacements of the bogie and hanging beam; and the radial stiffness is finally suggested to be around 1[Formula: see text]kN/mm by comprehensively considering all dynamic indexes. Increasing the initial compression displacement of guiding tyre can well limit the lateral displacements of the bogie and the hanging beam, thus enhancing the train running safety; however, it would intensify the vehicle-guideway lateral vibration level; especially, the optimal initial compression displacement of guiding tyre is related to its radial stiffness characteristics. To ensure a good curve negotiation performance of vehicle and guideway vibration level, the stiffness of the anti-roll torsion bar and the initial gradient angle of the installed trapezoid four-link suspended device are suggested to be 1.0[Formula: see text]MNm/rad and 65–[Formula: see text], respectively.

Theoretical and experimental studies of a novel nested oscillator with a high-damping characteristic

2020 ◽  
pp. 107754632094378
Author(s):  
Haiping Liu ◽  
Kaili Xiao ◽  
PengPeng Zhao ◽  
Dongmei Zhu
Keyword(s):  
Resonant Frequency ◽  
Vibration Suppression ◽  
Damping Ratio ◽  
Experimental Studies ◽  
Harmonic Balance Method ◽  
Design Parameters ◽  
Base Excitation ◽  
Oscillation System ◽  
Equivalent Damping ◽  
Vibration Transmissibility

Stiffness and damping of a structure usually show the opposite change so that the resonant frequency and the static load bearing capacity of a mechanical system often exhibit contradiction. To solve this dilemma, a novel high-damping oscillator which is constructed by a nested diamond structure with the purpose of enhancing the damping property is proposed in this study without reducing the overall systematic stiffness. The mathematical model and geometrical relationships are established at first. And then, the steady-state solutions under base excitation are derived by using the harmonic balance method and further verified by numerical simulation. In addition, the effects of some design parameters on the equivalent damping ratio for the high-damping oscillator are studied to reveal the nonlinear characteristic. Besides, the natural frequency of the nonlinear oscillator is also presented and investigated. By using the displacement transmissibility and comparing with the traditional linear isolator with the same overall stiffness, the vibration suppression performance of the high-damping oscillator is addressed. The obtained calculating results demonstrate that the vibration control performance of the high-damping oscillator outperforms the linear counterpart around resonant frequency. Moreover, the influences of systematic parameters of the high-damping oscillator for the base excitation case on the vibration transmissibility are also discussed, respectively. Finally, an experimental campaign is conducted on an in-house-built test rig to corroborate the accuracy of the analytical solutions of the high-damping oscillation system. The results discussed in this study provide a useful guideline, which can help to design this class of high-damping oscillation system.

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