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Principle and Experimental Verification of Caudal-fin-type Piezoelectric-stack Pump with Variable-cross-section Oscillating Vibrator

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Chinese Journal of Mechanical Engineering 2012年第1期25卷 128-136页

作者： HU Xiaoqi ZHANG Jianhui huang Yi XIA Qixiao huang weiqing ZHAO Chunsheng State Key Laboratory of Mechanics and Control of Mechanical Structures Nanjing University of Aeronautics and AstronauticsNanjing 210016China College of Mechanical&Electronic Engineering Beijing Union UniversityBeijing 100020China

In the traditional flow-resistance-differential (FRD) type valve-less piezoelectric pump, the generated outflow and pressure are discontinuous because of the inherent periodicity and fluctuation of the pump. To overcome these drawbacks, utilizing the bending vibration of piezoelectric bimorph to drive fluid was conducted. However, our investigation on the current status of this piezoelectric bimorph pump shows that larger driving force and vibration amplitude are required for fluid pumping; the pumping can be realized through the centrifugal force; and the mechanism of fluid pumping is no longer further studied. Based on these cases, the paper designed a piezoelectric-stack pump with variable-cross-section oscillating (VCSO) vibrator by imitating the swing of the caudal-fin of tuna, and the pump is neither the rotating type nor the volumetric type according to the taxonomy. The interaction between the oscillating vibrator and the fluid parcel is firstly analyzed from the viewpoint of momentum conservation, and the analytical expression of pump flow rate is obtained. Then the modal and harmonic response analyses on the vibrator immerged in water are carried out. From the analyses the first two orders resonance frequencies are 832 Hz and 1 939 Hz, respectively, and the peak value of the tip amplitude is 0.6 mm. Laser Doppler vibrometer is used to measure both the frequency and vibration amplitude, and the determined first two orders resonance frequencies are 617 Hz and 1 356 Hz, respectively. The measured tip amplitude reaches to the peak value of 0.3 mm. At last, experimental measurement for the flow rates with different driving frequencies is conducted. The results show that the flow rate can reach 560 mL/min at 1 370 Hz when the pump runs under the backpressure of 30 mm water column. And the flow rate is as much as 560% of that of experiment results carried out by researchers from Brazil. The proposed pump innovates in both theory and taxonomy; in addition, the pum

关键词： caudal-fin-type variable-cross-section piezoelectric-stack valve-less pump

Experiment on a Double-Foot Stepping Piezoelectric Linear Motor

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Transactions of Nanjing University of Aeronautics and Astronautics 2018年第3期35卷 423-431页

作者： Sun Mengxin huang weiqing Wang Yin Lu Qian State Key Laboratory of Mechanics and Control of Mechanical Structures College of Aerospace EngineeringNanjing University of Aeronautics and Astronautics School of Mechanical and Electric Engineering Guangzhou University Center for Precision Measurement Technologies and Instruments Huaqiao University

A novel double-foot piezoelectric linear motor is *** kinematic model of the motor under stepping motion is *** motor mainly consists of a stator with four piezoelectric stacks,a mover,a holding mechanism,and a preloading mechanism to achieve large stroke with high *** element simulations are carried out to analyze the motion characteristics of the motor.A prototype is fabricated and a serial experiments are conducted to validate the feasibility of the motor *** results indicate that the motor can move at a speed of 670.22μm/s with a driving frequency of 120 Hz and a voltage of 120 *** resolution of the proposed motor is 3.6μm while the resolution of the single-step motion is 0.1μm.

关键词： piezoelectric linear motor piezoelectric stack performance test

Progress in high-performance stick-slip piezoelectric actuators: a review

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International Journal of Smart and Nano Materials 2024年第3期15卷 652-696页

作者： Yingqi Lin Dawei An Zhenyu Lin Xiaoting Chen weiqing huang School of Mechanical and Electrical Engineering Guangzhou UniversityGuangzhouChina School of Computer and Information Qiannan Normal University for NationalitiesDuyunChina

The ultra-precision field is popular for its micro-nanometer positioning accuracy and large working *** actuators based on the stick-slip operational principle exhibit superior performance characteristics,making them stand out with unique advantages in this *** paper provides a comprehensive review of the developments in stick-slip piezoelectric actuators over recent *** with a detailed explanation of their operating principles,the article proceeds with a brief introduction to the more commonly used driving waveforms and their ***,various design and optimization technologies for existing com-pliant mechanisms are ***,stick-slip piezoelectric actuators are categorized based on different motion forms,including linear,rotary,and multi-degree of freedom *** category is thoroughly examined in terms of structural design and performance *** this,the discussion shifts toward controller method research and friction modeling analysis,featuring a particular emphasis on the advancements related to displacement back-lash suppression *** systematic summary aims to provide a reference for researchers within related fields,thereby facilitating the further development and application of stick-slip piezoelectric actuators.

关键词： Piezoelectric actuator stick-slip motion principle flexure mechanism positioning accuracy

Working Mechanism of a Kind of Non-resonant Linear Piezoelectric Motor with Flexible Driving End

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Transactions of Nanjing University of Aeronautics and Astronautics 2018年第5期35卷 749-759页

作者： Chen Xifu huang weiqing Lu Qian Li Ming Ren Yaoqing School of Mechanical Engineering Yancheng Institute of Technology State Key Laboratory of Mechanics and Control of Mechanical Structures Nanjing University of Aeronautics and Astronautics

A non-resonant piezoelectric linear motor with a flexible driving end,which has an extensive working frequency range and good operation stability,is studied theoretically and *** on the microscopic vibration characteristics of the motor stator,the longitudinal vibration model is established for the whole motor *** to the Coulomb friction model and the motor vibration model,the friction mechanism of the nonresonant piezoelectric linear motor is investigated by dynamical analysis of the whole motor ***,the vibration characteristics and mechanical output characteristics of the stator are simulated and experimentally studied on the basis of the friction drive mechanism ***,both the simulation and experimental results show that this kind of motor remain stable in the frequency domain from 2.2 kHz to 3.5 kHz and that when the pre-stress is 4 Nand the driving voltage is 90 V,the maximum velocity of the motor is above 4 mm/s and the maximum thrust is nearly 0.5 N.

关键词： piezoelectric motor non-resonance friction drive principle flexible drive end

Review on formation mechanism analysis method and control strategy of urban haze in China

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Chinese Journal of Chemical Engineering 2019年第7期27卷 1572-1577页

作者： weiqing huang Lirong Cai Haifeng Dang Zhe Jiao Hongbo Fan Faliang Cheng School of Environment and Civil Engineering Guangdong Engineering and Technology Research Center for Advanced NanomaterialsDongguan University of TechnologyDongguan 523808China Guangdong Provincial Key Lab of Green Chemical Product Technology South China University of TechnologyGuangzhou 510640China

Due to the rapid urbanization and industrialization,and excessive consumption of fossil fuel,haze weather characterized by PM2.5 has become a severe pollution problem in major Chinese cities recently,which has harmful effect on the air quality,visibility,clime system and human *** indicate suitable directions for the prevention and control of haze pollution,the pollutant source apportionment and formation mechanism of urban haze should be figured out *** this work,we briefly review the frequently-used methods for PM2.5 source apportionment and formation mechanism analysis of urban haze based on normal perspective in recent ***,based on the new perspective of systematic methodology,the utilization of fault tree approach for the causation mechanism analysis of urban haze is significantly introduced and ***,the recent progress on controlling strategies of urban haze in China is also synoptically introduced and *** is expected that more effective tool/method can be found,developed and employed for the causation mechanism analysis and risk management of urban haze in China.

关键词： Urban haze Fossil fuel Formation Sustainability

TransTM:A device-free method based on time-streaming multiscale transformer for human activity recognition

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Defence Technology（防务技术） 2024年第2期32卷 619-628页

作者： Yi Liu weiqing huang Shang Jiang Bobai Zhao Shuai Wang Siye Wang Yanfang Zhang Institute of Information Engineering Chinese Academy of Sciences School of Cyber SecurityUniversity of Chinese Academy of SciencesBeijingChina School of Information Management Beijing Information Science and Technology UniversityBeijingChina

RFID-based human activity recognition(HAR)attracts attention due to its convenience,noninvasiveness,and privacy *** RFID-based HAR methods use modeling,CNN,or LSTM to extract features ***,they have shortcomings:1)requiring complex hand-crafted data cleaning processes and 2)only addressing single-person activity recognition based on specific RF *** solve these problems,this paper proposes a novel device-free method based on Time-streaming Multiscale Transformer called *** model leverages the Transformer's powerful data fitting capabilities to take raw RFID RSSI data as input without ***,we propose a multiscale convolutional hybrid Transformer to capture behavioral features that recognizes singlehuman activities and human-to-human *** with existing CNN-and LSTM-based methods,the Transformer-based method has more data fitting power,generalization,and ***,using RF signals,our method achieves an excellent classification effect on human behaviorbased classification *** results on the actual RFID datasets show that this model achieves a high average recognition accuracy(99.1%).The dataset we collected for detecting RFID-based indoor human activities will be published.

关键词： Human activity recognition RFID Transformer

An end-to-end text spotter with text relation networks

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Cybersecurity 2021年第1期4卷 91-103页

作者： Jianguo Jiang Baole Wei Min Yu Gang Li Boquan Li Chao Liu Min Li weiqing huang Institute of Information Engineering Chinese Academy of SciencesBeijingChina School of Cyber Security University of Chinese Academy of ScienceBeijingChina Centre for Cyber Security Research and Innovation Deakin UniversityGeelongAustralia

Reading text in images automatically has become an attractive research topic in computer ***,end-to-end spotting of scene text has attracted significant research attention,and relatively ideal accuracy has been achieved on several ***,most of the existing works overlooked the semantic connection between the scene text instances,and had limitations in situations such as occlusion,blurring,and unseen characters,which result in some semantic information lost in the text *** relevance between texts generally lies in the scene *** the perspective of cognitive psychology,humans often combine the nearby easy-to-recognize texts to infer the unidentifiable *** this paper,we propose a novel graph-based method for intermediate semantic features enhancement,called Text Relation ***,we model the co-occurrence relationship of scene texts as a *** nodes in the graph represent the text instances in a scene image,and the corresponding semantic features are defined as representations of the *** relative positions between text instances are measured as the weights of edges in the established ***,a convolution operation is performed on the graph to aggregate semantic information and enhance the intermediate features corresponding to text *** evaluate the proposed method through comprehensive experiments on several mainstream benchmarks,and get highly competitive *** example,on the SCUT-CTW1500,our method surpasses the previous top works by 2.1%on the word spotting task.

关键词： Scene text spotting Graph convolutional network Visual reasoning

Highly stable capacitive tactile sensors with tunable sensitivity facilitated by electrostatic interaction of layered double hydroxide,MXene,and Ag NWs

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Science China(Technological Sciences) 2023年第11期66卷 3287-3297页

作者： SHEN GengZhe huang weiqing LI HaiFeng WANG FengMing SU DaoJian LI BaiJun ZHANG BoLun LIANG Ping ZHANG Chi XIN Yue HE Xin School of Applied Physics and Materials Wuyi UniversityJiangmen 529020China School of Materials and Energy Guangdong University of TechnologyGuangzhou 510006China

A capacitive tactile sensor(CTS)has been developed by assembling a double-sided patterned dielectric layer and novel *** patterned aluminium foil-supported electrode comprises zinc-aluminium layered double hydroxides(Zn AlLDH),MXene,and Ag NWs via electrostatic *** flexible device enables greater structural deformation,thereby enhancing sensitivity to a wide range of *** sensitivity of the CTS can be customized to meet specific requirements by matching the microstructured electrodes with the patterned dielectric *** optimized sensor exhibits a sensitivity of 2.752 kPa^(–1)within 30 kPa,a response time of approximately 100 ms,and a wide detection range of 0–300 *** strong physical interaction among the electrode materials ensures a reliable conductive network,ensuring the long-term stability of the sensor,even after 7500 loading and unloading ***,the fabricated CTS device presents a promising prospect for the integration into wearable electronics,with the ability to effectively respond to both human activities and external physical stimuli.

关键词： capacitive tactile sensor adjustable sensitivity long-term durability human activity monitoring

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分体挂壁空调内机贯流风机系统音质研究

家电科技 2015年第8期 63-65页

作者：黄伟青珠海格力电器股份有限公司广东珠海519070

运用CFD软件Fluent6.0对分别配置光面蜗舌和齿状蜗舌的风机系统进行二维流场的数值模拟,并同时对配置了这两种蜗舌的风机系统噪声和其他性能参数进行实验测量。通过对两者数值模拟与实际测量测数据的结果进行初步的分析,以探寻贯流风机... 详细信息

运用CFD软件Fluent6.0对分别配置光面蜗舌和齿状蜗舌的风机系统进行二维流场的数值模拟,并同时对配置了这两种蜗舌的风机系统噪声和其他性能参数进行实验测量。通过对两者数值模拟与实际测量测数据的结果进行初步的分析,以探寻贯流风机系统降噪、音质优化的指导性设计思路。

关键词：贯流风叶蜗舌涡流噪声数值模拟