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Flexible micro flow sensor for micro aerial vehicles

Rong ZHU, Ruiyi QUE, Peng LIU

《机械工程前沿(英文)》 2017年 第12卷 第4期   页码 539-545 doi: 10.1007/s11465-017-0427-0

摘要:

This article summarizes our studies on micro flow sensors fabricated on a flexible polyimide circuit board by a low-cost hybrid process of thin-film deposition and circuit printing. The micro flow sensor has merits of flexibility, structural simplicity, easy integrability with circuits, and good sensing performance. The sensor, which adheres to an object surface, can detect the surface flow around the object. In our study, we install the fabricated micro flow sensors on micro aerial vehicles (MAVs) to detect the surface flow variation around the aircraft wing and deduce the aerodynamic parameters of the MAVs in flight. Wind tunnel experiments using the sensors integrated with the MAVs are also conducted.

关键词: micro flow sensor     flexible sensor     surface flow sensing     aerodynamic parameter     micro aerial vehicle (MAV)    

A bionic approach for the mechanical and electrical decoupling of an MEMS capacitive sensor in ultralow

《机械工程前沿(英文)》 2023年 第18卷 第2期 doi: 10.1007/s11465-023-0747-1

摘要: Capacitive sensors are efficient tools for biophysical force measurement, which is essential for the exploration of cellular behavior. However, attention has been rarely given on the influences of external mechanical and internal electrical interferences on capacitive sensors. In this work, a bionic swallow structure design norm was developed for mechanical decoupling, and the influences of structural parameters on mechanical behavior were fully analyzed and optimized. A bionic feather comb distribution strategy and a portable readout circuit were proposed for eliminating electrostatic interferences. Electrostatic instability was evaluated, and electrostatic decoupling performance was verified on the basis of a novel measurement method utilizing four complementary comb arrays and application-specific integrated circuit readouts. An electrostatic pulling experiment showed that the bionic swallow structure hardly moved by 0.770 nm, and the measurement error was less than 0.009% for the area-variant sensor and 1.118% for the gap-variant sensor, which can be easily compensated in readouts. The proposed sensor also exhibited high resistance against electrostatic rotation, and the resulting measurement error dropped below 0.751%. The rotation interferences were less than 0.330 nm and (1.829 × 10−7)°, which were 35 times smaller than those of the traditional differential one. Based on the proposed bionic decoupling method, the fabricated sensor exhibited overwhelming capacitive sensitivity values of 7.078 and 1.473 pF/µm for gap-variant and area-variant devices, respectively, which were the highest among the current devices. High immunity to mechanical disturbances was maintained simultaneously, i.e., less than 0.369% and 0.058% of the sensor outputs for the gap-variant and area-variant devices, respectively, indicating its great performance improvements over existing devices and feasibility in ultralow biomedical force measurement.

关键词: micro-electro-mechanical system capacitive sensor     bionics     operation instability     mechanical and electrical decoupling     biomedical force measurement    

Effect of Joule heating on electro-osmotic flow in a closed-end micro-channel with isothermal and convective

Liang ZHAO, Linhua LIU,

《能源前沿(英文)》 2009年 第3卷 第4期   页码 381-388 doi: 10.1007/s11708-009-0057-2

摘要: The effect of Joule heating on the steady state electro-osmotic flow in a closed-end micro-channel is studied through numerical simulation with the finite volume method. The velocity field and the temperature field are described by a rigorous mathematical model. Thermophysical properties including viscosity and thermal conductivity are considered to be temperature-dependent. The simulations show that the presence of Joule heating causes an increase in temperature and a decrease in viscosity in the whole micro-channel, which, thereafter, induce a large velocity near the wall and an increase in fluid velocity at the central region in order to maintain a zero flow rate at the cross section of the micro-channel. The effect of Joule heating on the induced pressure gradient is also studied, which is very important for the application of the closed-end micro-channel as a micro-actuator. The results reveal that the induced pressure gradient, taking into consideration Joule heating, is significantly smaller than that without considering Joule heating when the wall temperature of the micro-channel is constant. The induced pressure gradient difference between considering Joule heating and without considering Joule heating is small under the convective boundary condition.

关键词: closed-end micro-channel     electrical double layer     electro-osmotic flow     induced pressure gradient     Joule heating    

Burnett simulations of gas flow and heat transfer in microchannels

Fubing BAO, Jianzhong LIN

《机械工程前沿(英文)》 2009年 第4卷 第3期   页码 252-263 doi: 10.1007/s11465-009-0037-6

摘要: In micro- and nanoscale gas flows, the flow falls into the transition flow regime. There are not enough molecule collisions and the gas deviates from the equilibrium. The Navier-Stokes equations fail to describe the gas flow in this regime. The direct simulation Monte Carlo method converges slowly and requires lots of computational time. As a result, the high-order Burnett equations are used to study the gas flow and heat transfer characteristics in micro- and nanoscale gas flows in this paper. The Burnett equations are first reviewed, and the augmented Burnett equations with high-order slip boundary conditions are then used to model the gas flow and heat transfer in Couette and Poiseuille flows in the transition regime.

关键词: micro- and nanoscale gas flow     slip-transition flow regime     Burnett equations     numerical simulation    

3D finite element prediction of chip flow, burr formation, and cutting forces in micro end-milling of

A. DAVOUDINEJAD, P. PARENTI, M. ANNONI

《机械工程前沿(英文)》 2017年 第12卷 第2期   页码 203-214 doi: 10.1007/s11465-017-0421-6

摘要:

Predictive models for machining operations have been significantly improved through numerous methods in recent decades. This study proposed a 3D finite element modeling (3D FEM) approach for the micro end-milling of Al6061-T6. Finite element (FE) simulations were performed under different cutting conditions to obtain realistic numerical predictions of chip flow, burr formation, and cutting forces. FE modeling displayed notable advantages, such as capability to easily handle any type of tool geometry and any side effect on chip formation, including thermal aspect and material property changes. The proposed 3D FE model considers the effects of mill helix angle and cutting edge radius on the chip. The prediction capability of the FE model was validated by comparing numerical model and experimental test results. Burr dimension trends were correlated with force profile shapes. However, the FE predictions overestimated the real force magnitude. This overestimation indicates that the model requires further development.

关键词: 3D finite element modeling     micro end-milling     cutting force     chip formation     burr formation    

Impact force detection using an energy flow estimator with piezoelectric sensors

Xingjun WANG, Daniel GUYOMAR, Kaori YUSE, Mickaël LALLART, Lionel PETIT,

《机械工程前沿(英文)》 2010年 第5卷 第2期   页码 194-203 doi: 10.1007/s11465-010-0004-2

摘要: Currently, there are numerous methods for estimating impact locations. One is to find more detailed information because the system becomes complicated. Another method is to reduce energy, for which various autonomic energy harvesting methods have been developed. However, the occupied energy is still small. This paper proposes a simple, rapid, and low-powered impact estimation method based on energy flow direction estimation through a pair of piezoelectric sensors. The estimation energy flow is expressed by a Poynting vector subsequently linked to piezoelectric sensor voltage outputs. The presented approach is verified by numerical simulations and experiments.

关键词: impact detection     energy flow     piezoelectric sensor     thin plate    

低高宽比矩形微通道中流动沸腾的压降特性

张炳雷,徐进良,肖泽军

《中国工程科学》 2007年 第9卷 第12期   页码 86-93

摘要: 以甲醇为工质,在不同进口温度、质量流率、热流密度和倾角下,对低高宽比矩形微通道中流动沸腾压降特性进行了研究,并分别采用均相模型和分相模型对通道压降进行了计算。通过对比实验结果与计算结果发现,均相模型中两相平均粘度的计算应当采用Dukler公式,用其他计算式时误差较大;利用LockhartMartinelli关系式进行的分相模型计算发现,现有C值计算公式,如Chisholm,Lee and Lee,Mishima及Qu and Mudawar等,都不能用于预测该实验中低高宽比微通道的两相压降。实验发现当通

关键词: 压降特性;均相模型;分相模型;微通道;流动沸腾    

油气田监测高性能微传感器及数字化系统

赵玉龙,牛 喆,周冠武,赵立波,蒋庄德

《中国工程科学》 2013年 第15卷 第1期   页码 99-105

摘要:

针对油气田特殊环境要求,介绍了一种高温高压传感器芯片的设计及加工制造方法,并研发了相关的高性能数字变送系统。所设计的高温高压传感器芯片解决了传统压阻式传感器在高温高压环境下的热稳定性问题,通过数字补偿技术进一步提升了其系统的线性度与精度,并针对油气田监测环境扩展了其相关外围设备。同时,为了适应油气田管监测理要求,设计了相关无线传感网络,以确保其工业生产的高效运行和有效控制。通过具体实验测试数据,验证了该油气田监测高性能微传感器及数字化系统的高精度及高可靠性,该系统的精度达到0.2 % FS及以上,达到世界先进水平,对国内的石化工业发展有着非常重要的意义。

关键词: 高温高压传感器芯片     高性能数字变送系统     数字补偿技术     无线传感网络     高精度    

Biomedical sensor technologies on the platform of mobile phones

Lin LIU, Jing LIU

《机械工程前沿(英文)》 2011年 第6卷 第2期   页码 160-175 doi: 10.1007/s11465-011-0216-0

摘要:

Biomedical sensors have been widely used in various areas of biomedical practices, which play an important role in disease detection, diagnosis, monitoring, treatment, health management, and so on. However, most of them and their related platforms are generally not easily accessible or just too expensive or complicated to be kept at home. As an alternative, new technologies enabled from the mobile phones are gradually changing such situations. As can be freely available to almost everyone, mobile phone offers a unique way to improve the conventional medical care through combining with various biomedical sensors. Moreover, the established systems will be both convenient and low cost. In this paper, we present an overview on the state-of-art biomedical sensors, giving a brief introduction of the fundamental principles and showing several new examples or concepts in the area. The focus was particularly put on interpreting the technical strategies to innovate the biomedical sensor technologies based on the platform of mobile phones. Some challenging issues, including feasibility, usability, security, and effectiveness, were discussed. With the help of electrical and mechanical technologies, it is expected that a full combination between the biomedical sensors and mobile phones will bring a bright future for the coming pervasive medical care.

关键词: biomedical sensor     pervasive technology     mobile phone     combined system     health management    

静电力驱动的悬臂梁微型电场传感器件 Article

韩志飞, 胡军, 李立浧, 何金良

《工程(英文)》 2023年 第24卷 第5期   页码 184-191 doi: 10.1016/j.eng.2022.06.017

摘要:

随着智能电网和能源互联网的发展,大规模实时电压/电场监测成为电力系统的迫切需求,这依赖于先进传感器件的大规模布置。电场测量在电力系统中具有重要意义。一方面,基于电场测量的电压反演可以实现高电压的非接触式测量,替代传统高压互感器,从而减少测量设备绝缘成本和安装难度;另一方面,电场测量还可以被应用于设备故障诊断、雷电预警、电磁环境测量等应用场景。传统的电场测量设备,如场磨等,往往体积大、成本高,无法大规模灵活布置。本文提出了一种静电力驱动的压阻式微型电场传感器。传感器被设计为四悬臂结构,悬臂在静电力的驱动下产生位移和应变,通过压阻材料转化为可测信
号。所提出的传感器具有尺寸小、成本低、功耗低、易于批量生产的优点。同时,该传感器还具有高信噪比、高分辨率及宽电场测量范围的特点。实验结果表明,所提出的传感器具有1.1~1100.0 kV·m−1的线性测量范围、112 V·m−1·Hz−1/2的交流电场分辨率以及496 Hz的截止频率。这一微型电场传感器将在智能电网及能源互联网中具有广泛的应用价值。

关键词: 微型传感器     电气传感器件     微加工工艺     压阻器件    

Development and testing of a wireless smart toolholder with multi-sensor fusion

《机械工程前沿(英文)》 2023年 第18卷 第4期 doi: 10.1007/s11465-023-0774-y

摘要: The smart toolholder is the core component in the development of intelligent and precise manufacturing. It enables in situ monitoring of cutting data and machining accuracy evolution and has become a focal point in academic research and industrial applications. However, current table and rotational dynamometers for milling force, vibration, and temperature testing suffer from cumbersome installation and provide only a single acquisition signal, which limits their use in laboratory settings. In this study, we propose a wireless smart toolholder with multi-sensor fusion for simultaneous sensing of milling force, vibration, and temperature signals. We select force, vibration, and temperature sensors suitable for smart toolholder fusion to adapt to the cutting environment. Thereafter, structural design, circular runout, dynamic balancing, static stiffness, and dynamic inherent frequency tests are conducted to assess its dynamic and static performance. Finally, the smart toolholder is tested for accuracy and repeatability in terms of force, vibration, and temperature. Experimental results demonstrate that the smart toolholder accurately captures machining data with a relative deviation of less than 1.5% compared with existing force gauges and provides high repeatability of milling temperature and vibration signals. Therefore, it is a smart solution for machining condition monitoring.

关键词: wireless smart toolholder     multi-sensor fusion     circular runout     dynamic balancing     static stiffness     dynamic inherent frequency    

Fault diagnosis of axial piston pumps with multi-sensor data and convolutional neural network

《机械工程前沿(英文)》 2022年 第17卷 第3期 doi: 10.1007/s11465-022-0692-4

摘要: Axial piston pumps have wide applications in hydraulic systems for power transmission. Their condition monitoring and fault diagnosis are essential in ensuring the safety and reliability of the entire hydraulic system. Vibration and discharge pressure signals are two common signals used for the fault diagnosis of axial piston pumps because of their sensitivity to pump health conditions. However, most of the previous fault diagnosis methods only used vibration or pressure signal, and literatures related to multi-sensor data fusion for the pump fault diagnosis are limited. This paper presents an end-to-end multi-sensor data fusion method for the fault diagnosis of axial piston pumps. The vibration and pressure signals under different pump health conditions are fused into RGB images and then recognized by a convolutional neural network. Experiments were performed on an axial piston pump to confirm the effectiveness of the proposed method. Results show that the proposed multi-sensor data fusion method greatly improves the fault diagnosis of axial piston pumps in terms of accuracy and robustness and has better diagnostic performance than other existing diagnosis methods.

关键词: axial piston pump     fault diagnosis     convolutional neural network     multi-sensor data fusion    

Dependence of error sensitivity of frequency on bias voltage in force-balanced micro accelerometer

Lili CHEN, Wu ZHOU

《机械工程前沿(英文)》 2013年 第8卷 第2期   页码 146-149 doi: 10.1007/s11465-013-0260-z

摘要:

To predict more precisely the frequency of force-balanced micro accelerometer with different bias voltages, the effects of bias voltages on error sensitivity of frequency is studied. The resonance frequency of accelerometer under closed loop control is derived according to its operation principle, and its error sensitivity is derived and analyzed under over etching structure according to the characteristics of Deep Reaction Ion Etching (DRIE). Based on the theoretical results, micro accelerometer is fabricated and tested to study the influences of AC bias voltage and DC bias voltage on sensitivity, respectively. Experimental results indicate that the relative errors between test data and theory data are less than 7%, and the fluctuating value of error sensitivity under the range of voltage adjustment is less than 0.01 μm . It is concluded that the error sensitivity with designed parameters of structure, circuit and process error can be used to predict the frequency of accelerometer with no need to consider the influence of bias voltage.

关键词: Micro-Electro-Mechanical Systems (MEMS)     micro accelerometer     force-balanced micro accelerometer     frequency     error sensitivity    

Reduced texaphyrin: A ratiometric optical sensor for heavy metals in aqueous solution

Harrison D. Root, Gregory Thiabaud, Jonathan L. Sessler

《化学科学与工程前沿(英文)》 2020年 第14卷 第1期   页码 19-27 doi: 10.1007/s11705-019-1888-y

摘要: We report here a water-soluble metal cation sensor system based on the as-prepared or reduced form of an expanded porphyrin, texaphyrin. Upon metal complexation, a change in the redox state of the ligand occurs that is accompanied by a color change from red to green. Although long employed for synthesis in organic media, we have now found that this complexation-driven redox behavior may be used to achieve the naked eye detectable colorimetric sensing of several number of less-common metal ions in aqueous media. Exposure to In(III), Hg(II), Cd(II), Mn(II), Bi(III), Co(II), and Pb(II) cations leads to a colorimetric response within 10 min. This process is selective for Hg(II) under conditions of competitive analysis. Furthermore, among the subset of response-producing cations, In(III) proved unique in giving rise to a ratiometric change in the ligand-based fluorescence features, including an overall increase in intensity. The cation selectivity observed in aqueous media stands in contrast to what is seen in organic solvents, where a wide range of texaphyrin metal complexes may be prepared. The formation of metal cation complexes under the present aqueous conditions was confirmed by reversed phase high-performance liquid chromatography, ultra-violet-visible absorption and fluorescence spectroscopies, and high-resolution mass spectrometry.

关键词: texaphyrin     fluorescent sensor     ion-sensing     indium     mercury    

Numerical simulation of micro scale flowing and boiling

Wen WANG, Rui ZHUAN,

《能源前沿(英文)》 2009年 第3卷 第4期   页码 396-401 doi: 10.1007/s11708-009-0049-2

摘要: Numerical simulations of flowing and boiling in micro channels are presented, including the modeling of bubble dynamics of nucleate boiling, and a description of the interface of two phases with the volume-of-fluid (VOF). The two calculated cases are compared with related experimental data in literature. Some simulated results are found corresponding well to the experimental data. The simulated results also show the details of 3-dimensional heat transfer and the flow in micro channels, which are helpful to the investigation of the mechanism of two-phase heat transfer and flow in micro channels.

关键词: volume-of-fluid (VOF)     micro channel     nucleate boiling     bubble dynamics     simulation    

标题 作者 时间 类型 操作

Flexible micro flow sensor for micro aerial vehicles

Rong ZHU, Ruiyi QUE, Peng LIU

期刊论文

A bionic approach for the mechanical and electrical decoupling of an MEMS capacitive sensor in ultralow

期刊论文

Effect of Joule heating on electro-osmotic flow in a closed-end micro-channel with isothermal and convective

Liang ZHAO, Linhua LIU,

期刊论文

Burnett simulations of gas flow and heat transfer in microchannels

Fubing BAO, Jianzhong LIN

期刊论文

3D finite element prediction of chip flow, burr formation, and cutting forces in micro end-milling of

A. DAVOUDINEJAD, P. PARENTI, M. ANNONI

期刊论文

Impact force detection using an energy flow estimator with piezoelectric sensors

Xingjun WANG, Daniel GUYOMAR, Kaori YUSE, Mickaël LALLART, Lionel PETIT,

期刊论文

低高宽比矩形微通道中流动沸腾的压降特性

张炳雷,徐进良,肖泽军

期刊论文

油气田监测高性能微传感器及数字化系统

赵玉龙,牛 喆,周冠武,赵立波,蒋庄德

期刊论文

Biomedical sensor technologies on the platform of mobile phones

Lin LIU, Jing LIU

期刊论文

静电力驱动的悬臂梁微型电场传感器件

韩志飞, 胡军, 李立浧, 何金良

期刊论文

Development and testing of a wireless smart toolholder with multi-sensor fusion

期刊论文

Fault diagnosis of axial piston pumps with multi-sensor data and convolutional neural network

期刊论文

Dependence of error sensitivity of frequency on bias voltage in force-balanced micro accelerometer

Lili CHEN, Wu ZHOU

期刊论文

Reduced texaphyrin: A ratiometric optical sensor for heavy metals in aqueous solution

Harrison D. Root, Gregory Thiabaud, Jonathan L. Sessler

期刊论文

Numerical simulation of micro scale flowing and boiling

Wen WANG, Rui ZHUAN,

期刊论文