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IEEE/ASME International Conference on Advanced Intelligent Mechatronics (AIM)

作者： Lu, Shizhou Liu, Yaxin Yao, Yufeng Huang, Bo Sun, Lining Harbin Inst Technol Weihai State Key Lab Robot & Syst Weihai 264209 Peoples R China Harbin Inst Technol State Key Lab Robot & Syst Harbin 150001 Peoples R China Harbin Inst Technol Weihai State Key Lab Robot & Syst Weihai Harbin 264209 Peoples R China

ISBN: (纸本)9781479957361

The paper presents a new type of piezostack driven jetting dispenser, which can be applied to dispense high viscosity adhesives in microelectronic packaging process. According to the bond graph technique, a dynamic model and governing equations are derived from integrating the sub-models of the electromechanical part and the fluid part of the dispenser. Based on the proposed model, the jetting dispenser is manufactured, and its performance is then evaluated through both computer simulation and experimental investigation. The results verify the dispenser's jetting ability and the model's validity, and provide support for the design and control studies of the proposed dispenser.

关键词： jetting dispenser piezostack high viscosity bond graph

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Development and validation of a refined piezostack-actuated trailing edge flap actuator for a helicopter rotor

Development and validation of a refined piezostack-actuated ...

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Smart Structures and Materials 1999 Conference

作者： Lee, T Chopra, I Univ Maryland Alfred Gessow Rotorcraft Ctr Dept Aerosp Engn College Pk MD 20742 USA

ISBN: (纸本)0819431427

A methodology to develop piezostack-based actuator for trailing edge flap on a full-scale helicopter rotor blade is presented. By a systematic down-selection approach through the experimental validation on piezostack characteristics, one among numerous candidates was chosen for current study, which has higher stiffness as well as good strain/block force capability. The prototype actuator was designed and fabricated using two pieces of selected piezostack incorporated with a double-lever amplification mechanism that extends a lever-fulcrum amplification concept. To validate the feasibility of the designed actuator,the prototype actuator was tested in vacuum chamber that simulates the centrifugal force environment. It was shown that the actuator operated with no major degradation in performance up to 600g of centrifugal loading. The present actuator has a capability of oscillating the trailing edge flap to the required deflection/frequency to actively control rotor vibration in the rotating environment. Then, a further design refinement was considered to reduce the drawbacks, which finally results in an improved actuator with peak actuation force of 80 lbs at 38 mils stroke.

关键词： piezostack L-L actuator mechanical amplification individual blade control trailing edge flap

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Design and static testing of a trailing-edge flap actuator with piezostacks for a rotor blade

Design and static testing of a trailing-edge flap actuator w...

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SPIE Conference on Smart Structures and Integrated Systems

作者： Lee, T Chopra, I Univ Maryland Dept Aerosp Engn Alfred Gessow Rotorcraft Ctr College Pk MD 20742 USA

ISBN: (纸本)081942773X

This paper presents the development of an actuator for a trailing edge flap on a full-scale helicopter rotor blade using a high performance piezoelectric stack device. The actuator was designed and constructed using two identical piezostacks that were selected among commercially available actuators through a systematic testing. To calculate the aerodynamic requirement of the flap actuator, an analytical model was formulated using quasi-steady aerodynamics. A new amplification device utilizing double-lever mechanism was designed and fabricated. An amplification factor of 19.4 and the constant response covering up to 8/rev were obtained experimentally under non-rotating condition. It was shown that the present flap actuator is capable of achieving the required flap deflection to actively control rotor vibration.

关键词： piezostack flap actuator rotor blade trailing edge flap mechanical amplification

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Analysis of the displacement amplification ratio of bridge-type flexure hinge

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SENSORS AND ACTUATORS A-PHYSICAL 2006年第2期132卷 730-736页

作者： Ma, Hong-Wen Yao, Shao-Ming Wang, Li-Quan Zhong, Zhi Harbin Engn Univ Harbin Peoples R China Harbin Inst Technol Harbin 150006 Peoples R China

The bridge-type flexure hinge is a classic displacement amplification mechanism. The existing models of theoretic displacement amplification ratio of bridge-type flexure hinges are not perfect. This makes it very difficult to design and manufacture a satisfactory structure using these models. Kinematic theory was used to analyze the ideal displacement amplification ratio of a bridge-type flexure hinge in this paper, and the flexure hinge was regarded as a pure multi-rigid body with ideal pivots. Elastic beam theory was used to analyze the theoretic displacement amplification ratio when considering the translational and rotational stiffness of the flexure pivots. The model of theoretic displacement amplification ratio explains why the bridge-type displacement amplification mechanism has an amplification ratio extremum and where the threshold is. The finite element method was used for comparison with the mathematical model, and similar results were obtained. Finally, the finite element method was used to analyze the shape mode of the structure. The result showed that increasing the amplification ratio by decreasing the thickness of the flexure pivots led to a decrease in the mode shape frequency of the bridge-type structure. Thus, redesigning of the structure was needed to solve the problem. (c) 2005 Elsevier B.V. All rights reserved.

关键词： flexure hinge bridge-type piezostack displacement amplification ratio finite element method (FEM)

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A hybrid vibration isolator: Design, control, and experiments

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PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART C-JOURNAL OF MECHANICAL ENGINEERING SCIENCE 2016年第17期230卷 2982-2995页

作者： Zhang, Yang Chen, Zhaobo Jiao, Yinghou Harbin Inst Technol Sch Mechatron Engn Harbin 150001 Peoples R China

A hybrid vibration isolator (HVI) is presented with its structure, dynamic model, control strategy and preliminary experiments. The HVI is composed of the active piezostack actuator and the passive rubber isolator, which has compact structure and high reliability. Based on the dynamic model and the formula derivation of the transmissibility, the control algorithm is established using the linear quadratic regulator method. The simulations indicate that the vibrations acting on the load platform are vastly reduced, where the active piezostack-based actuator can eliminate the resonance peak significantly. Moreover, the passive rubber-based isolator is effective to isolate a part of vibration once active control fails. Finally, an experimental system is built up to implement integrated passive and active vibration control using the HVI prototype. The experimental results verify the theoretical analysis work.

关键词： Vibration isolation active-passive control piezostack linear quadratic regulator control compact structure

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Study on a Piezohydraulic Motor for Maximal Energy Efficiency

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JOURNAL OF INTELLIGENT MATERIAL SYSTEMS AND STRUCTURES 2010年第14期21卷 1447-1458页

作者： Kan, Junwu Wen, Jianming Zhang, Zhonghua Zeng, Ping Wang, Shuyun Cheng, Guangming Zhejiang Normal Univ Inst Precis Machinery & Instrument Jinhua 321004 Peoples R China

A piezohydraulic linear motor driven by a piezostack diaphragm pump is presented and studied. The diaphragm of pump chamber consists of a membrane and rigid disk, instead of a single piston or membrane. An analytical model is established to evaluate piezohydraulic motor performance in terms of velocity, pushing force, mechanical energy conversion efficiency (MEE), and electromechanical energy conversion efficiency (EMEE). The involved effect factors of motor performance are radius ratio (rigid-disk radius to chamber radius), area ratio (pump-chamber area to cylinder-piston area), force ratio (external load to blocked force of piezostack), and step ratio (cylinder-piston stroke to free displacement of piezostack). Analytical results show that there are optimal structural parameters (radius ratio and area ratio) for property parameters (force ratio, step ratio, MEE, and EMEE) to obtain maximal values. Considering the achievable peak MEE and EMEE, the design method was introduced for different purpose of applications. A piezohydraulic motor was fabricated and tested to examine the influence of radius ratio on performance of the piezohydraulic motor. The experimental results show that both the motor velocity and driving force can be enhanced with optimizing radius ratio.

关键词： piezostack piezohydraulic pump piezohydraulic motor energy efficiency theoretical analysis

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Study on a piezohydraulic pump for linear actuators

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SENSORS AND ACTUATORS A-PHYSICAL 2009年第2期149卷 331-339页

作者： Kan, Junwu Tang, Kehong Ren, Yu Zhu, Guoren Li, Peng Jilin Univ Coll Mech Sci & Engn Changchun 130025 Peoples R China Jilin Univ Coll Math Changchun 130012 Peoples R China

To obtain high flowrate and pressure. a piezostack pump with stiffened chamber diaphragm (consisting of a membrane and rigid disk) was presented and studied. An analytical model for performance evaluation is established based on the theory of plate and shells. The effect of chamber diaphragm parameters on flowrate, pressure and output energy coefficient. and that of external load on flowrate and output energy coefficient were analyzed. Considering the influence of the diaphragm stiffness on dynamic-response performance of the piezostack actuator, the design method was introduced. Analysis results show that all of the flowrate, backpressure and Output energy coefficient increase with the decreasing of membrane thickness. There is an optimal radius ratio (rigid-disk radius to membrane radius) for flowrate and pressure to achieve peak value, which decreases with the raising of the membrane thickness. On the other hand, output energy coefficient, which decreases with the increasing of radius ratio. achieves peak when force ratio (external load to blocked force of piezostack) is 0.5. At stiffness match and optimal load, maximal output energy coefficient is independent of membrane thickness, and flowrate decreases with the increasing of membrane thickness. To examine analytical results, a check-valve piezostack pump was fabricated and tested. The experiment results show that the flowrate can be enhanced with optimizing rigid disk. (C) 2008 Elsevier B.V. All rights reserved.

关键词： Piezoelectric pump piezostack Piezohydraulic pump Piezohydraulic actuator Analytical analysis

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Measurement of static force at liquid helium temperature

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MEASUREMENT SCIENCE AND TECHNOLOGY 2007年第8期18卷 2356-2364页

作者： Sekalski, P. Napieralski, A. Fouaidy, M. Bosotti, A. Paparella, R. Tech Univ Lodz DMCS PL-90924 Lodz Poland Univ Paris 11 IPNO CNRS IN2P3 Paris France Ist Nazl Fis Nucl I-20133 Milan Italy

The multilayer piezostacks which are integrated into a cold tuning electromechanical system are used for the compensation of the Lorentz force and damping of microphonics. Cold tuning systems are tested in the CHECHIA horizontal test stand and in the vacuum ultraviolet free electron laser VUV-FEL, both built at DESY-Hamburg. One of the most important issues for the used active element's lifetime is a correct initial preloading force. The commonly used method for measuring preload is based on a strain gauge and requires an additional sensor and wiring. The authors propose an alternative method where the piezostacks are used as force sensors. More precisely, the capacitance and the impedance change of the piezostacks were investigated. The resonance peaks, which are visible on the impedance versus frequency curve, shift when the static force is applied to piezostacks. Moreover, the value of the piezostacks capacitance increases with applied static force. A measurement performed at room and at LHe temperature (T < 4.2 K) showed that this behaviour ( frequency shift and capacitance increase) might be used for the precise measurement of static force in the temperature range 1.8 K-300 K. Using this method it is possible to estimate in situ the preload force applied to the piezoelectric element.

关键词： static force cryogenic operation piezostack

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Rigid design of fast scanning probe microscopes using finite element analysis

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ULTRAMICROSCOPY 2004年第3-4期100卷 259-265页

作者： Kindt, JH Fantner, GE Cutroni, JA Hansma, PK Univ Calif Santa Barbara Dept Phys Santa Barbara CA 93106 USA

To improve the performance of atomic force microscopes regarding speed and noise sensitivity, it is important to consider the mechanical rigidity of the actuator (scanner), and the overall mechanical structure. Using finite element analysis in the design process, it was possible to increase the first resonance frequency from 950 Hz for the whole system to 23.4 kHz for the whole system. This constitutes a factor of similar to25 in resonance frequency and a factor of 625 in stiffness and, hence, noise immunity. (C) 2004 Elsevier B.V. All rights reserved.

关键词： AFM fast scanning probe microscope rigid design piezoscanner piezostack finite element analysis FEA

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Normally-closed peristaltic micropump with re-usable actuator and disposable fluidic chip

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SENSORS AND ACTUATORS B-CHEMICAL 2011年第2期154卷 137-141页

作者： Trenkle, F. Haeberle, S. Zengerle, R. Univ Freiburg Lab MEMS Applicat Dept Microsyst Engn IMTEK D-79110 Freiburg Germany HSG IMIT D-78052 Villingen Schwenningen Germany Univ Freiburg Ctr Biol Signalling Studies Bioss D-7800 Freiburg Germany

We present a new peristaltic micropump offering three key features: (i) a disposable pump body and a reuseable actuator unit, (ii) an intrinsic normally-closed mechanism blocking unintended liquid flows up to a pressure of 100 kPa and (iii) a backpressure independent pump performance up to 40 kPa. The modular concept basing on a re-usable actuator unit and a low-cost disposable microfluidic chip enables an easy and cost-efficient exchange of all contaminated parts after use, which addresses especially the needs in the health care sector. The intrinsic normally-closed feature blocks liquid flow in both directions up to a pressure difference of 100 kPa when the electric power is off. The micropump is actuated in a peristaltic manner by three piezostack actuators. Up to a frequency of 15 Hz the pump rate increases linearly with operation frequency leading to a pump rate of 120 mu L/min. This was proved for an operation voltage of 140V by pumping water. In addition the pump rate is independent on backpressure up to 40 kPa and shows a linear decrease for higher pressure differences. The maximum achievable backpressure at zero flow rate was extrapolated to be 180 kPa. As for all peristaltic micropumps, the pump is bidirectional, e.g. the pump direction can be changed forward to reverse mode. (C) 2010 Elsevier B.V. All rights reserved.

关键词： Microfluidics Micropump Microvalve Normally-closed Modular piezostack

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