共查询到20条相似文献,搜索用时 15 毫秒
1.
Vyshnevskyy O Kovalev S Wischnewskiy W 《IEEE transactions on ultrasonics, ferroelectrics, and frequency control》2005,52(11):2047-2053
A new type of piezoelectric plate actuator for ultrasonic linear motors has been developed. These new piezoelectric actuators use the principle of asymmetric resonant excitation of the piezoceramic plate in a special resonant mode consisting of a standing two-dimensional extensional wave in a piezoceramic plate. The behavior of the actuator has been simulated with finite-element method (FEM) software and the simulation results checked with single-point contact measurements on the surface of the actuator. This paper describes this work and closes by describing the new ultrasonic translation stages based on this design. 相似文献
2.
Topology optimization design of flextensional actuators 总被引:8,自引:0,他引:8
Silva EN Nishiwaki S Kikuchi N 《IEEE transactions on ultrasonics, ferroelectrics, and frequency control》2000,47(3):657-671
Flextensional actuators can be defined as a piezoceramic (or a stack of piezoceramics) connected to a flexible mechanical structure that converts and amplifies the output displacement of the piezoceramic. Essentially, the actuator performance depends on the distribution of stiffness and flexibility in the coupling structure and, therefore, on the coupling structure topology. In this work, we propose a general method for designing flextensional actuators with large output displacement (or generative force) by applying the topology optimization method. The goal is to design a flexible structure coupled to the piezoceramic that maximizes the output displacement (or force) in some specified direction. Static and low frequency applications are considered. To illustrate the implementation of the method, 2-D topologies of flextensional actuators are presented because of the lower computational cost; however, the method can be extended to 3-D topologies. By designing other types of coupling structures connected to the piezoceramic, new designs of flextensional actuators that produce output displacements or forces in different directions can be obtained, as shown. This method can be extended for designing flextensional hydrophones and sonars. 相似文献
3.
Studies on muscle mimicking actuators have increased in the last two decades due to the possibility of various applications for compact lightweight actuators including small unmanned aircrafts, missile, and biomimetic robots. Piezoelectric materials have been used in a variety of applications ranging from shape control of structure and active vibration control of structure to noise suppression due to compact size and good frequency response. Conventional polycrystal piezoelectric ceramic materials, however, have limited actuating strains and displacement, hindering their use in actuators for small aerospace vehicles. In this study, the design and fabrication method of an actuator with a piezoelectric single-crystal layer were investigated to increase the actuation strain and displacement. From a comparison of the performance of the LIPCA-C2 and LIPCA-S prototypes, it was found that the new LIPCA-S2, which has much higher coefficient of the unimorph actuator, can generate an actuating displacement more than twice that of LIPCA-C2. 相似文献
4.
Due to their anisotropy multilayered fibre-reinforced polymers tend to generate residual stresses, which are primarily influenced by thermal and hygroscopic processes. In the case of an unsymmetric reinforcement architecture, those residual stresses may induce large out-of-plane deformations in thin-walled laminates. Here, specific stacking sequences support the development of so called bistable laminates which are characterised by two distinct deformation states which can be converted by applying forces or bending moments. In combination with appropriate actuator systems, like piezoceramic transducers, such bistable composites can purposefully be used to design compliant mechanisms and novel morphing structures that stand out for a permanent change of shape only by a small energy supply. For the structural analysis and the computation of the necessary actuation voltage to initiate the snap-through of bistable composite structures with piezoceramic actuators, non-linear semi-analytical and numerical simulation methods have been elaborated. First active bistable prototypes have been manufactured and successfully tested. 相似文献
5.
This paper introduces the Dual Electro/Piezo Property (DEPP) gradient technique via Micro-Fabrication through Co-eXtrusion
(MFCX) which pairs a high displacement lead zirconate titanate (PZT) piezoceramic with a high permittivity barium titanate
(BT) dielectric. By grading with this material combination spatially across an actuator, the electric field is concentrated
in the more active region for improved efficiency, higher displacements, and complex motions. To aid in synthesis and analysis
of any gradient profile, compositional maps are provided for key material properties (density, stiffness, permittivity, and
piezoelectric coefficients). The DEPP technique was validated, independent of the MFCX process, by powder pressing a conventional
bimodal gradient beam which demonstrated through experiments high displacement capabilities at lower driving potentials than
comparable functionally graded piezoceramic actuators. For more complex gradients, the MFCX process was adapted to the DEPP
gradient technique and illustrated by the fabrication of a linearly graded prototype whose monolithic nature and gradual material
variation significantly reduces internal stresses, improves reliability, and extends service lifetime. 相似文献
6.
Smithmaitrie P Suybangdum P Laoratanakul P Muensit N 《IEEE transactions on ultrasonics, ferroelectrics, and frequency control》2012,59(5):1033-1042
In this work, design and performance testing of an ultrasonic linear motor with dual piezoelectric actuator patches are studied. The motor system consists of a linear stator, a pre-load weight, and two piezoelectric actuator patches. The piezoelectric actuators are bonded with the linear elastic stator at specific locations. The stator generates propagating waves when the piezoelectric actuators are subjected to harmonic excitations. Vibration characteristics of the linear stator are analyzed and compared with finite element and experimental results. The analytical, finite element, and experimental results show agreement. In the experiments, performance of the ultrasonic linear motor is tested. Relationships between velocity and pre-load weight, velocity and applied voltage, driving force and applied voltage, and velocity and driving force are reported. The design of the dual piezoelectric actuators yields a simpler structure with a smaller number of actuators and lower stator stiffness compared with a conventional design of an ultrasonic linear motor with fully laminated piezoelectric actuators. 相似文献
7.
Piezoelectric fiber composites were developed to overcome drawbacks of typical monolithic piezoceramic (PZT) actuators. Although piezoelectric fiber composites had many improvements over the monolithic PZT, there are still improvements. Thus, the single crystal piezoelectric fiber composite actuator is proposed. Single crystal piezoelectric materials such as PMN-PT have larger piezoelectric strain constants, higher bandwidth and higher energy density than polycrystalline counterparts. Piezoelectric fiber composites can improve the performance of various structures, and can be subject to wide temperature range where the thermoelastic behavior is important. Therefore, this paper studies the coefficients of thermal expansion (CTE) for single crystal piezoelectric fiber composites. The Macro Fiber Composite (MFC) as the piezoelectric fiber composite is considered. To calculate the effective properties of two orthotropic layers of the MFC, PMN-PT(or PZT)/epoxy and copper/epoxy layers, the rule of mixture is adopted. With the effective properties known for each layers, the two CTE of the MFC actuator are obtained from the classical lamination theory considering thermal effects. The difference of the CTE between the single crystal MFC and the standard MFC is studied. 相似文献
8.
P. K?dzioraA. Muc 《Composite Structures》2012,94(3):1224-1235
In this paper, dynamics, electromechanical couplings, and control of piezoelectric laminated cylindrical shells and rectangular plates are investigated. It is assumed that the piezoelectric layers are distributed on the top and bottom surfaces of the structures. First of all the governing equations and boundary conditions including elastic and piezoelectric couplings are formulated and solutions are derived. Then control of the plate/shells deflections and natural frequencies using high control voltages are studied in order to optimize the structural response. The present formulation of optimal design introduces boundaries of piezoelectric patches as new class of design variables. In addition, classical design variables in the form of ply orientation angles of orthotropic layers are also taken into account. For the actuator/actuator configuration, it was shown that the piezoelectric actuators can significantly reduce deformations/eigenfrequencies of the composite plate. Those effects were dependent on the value of the applied voltage. It was demonstrated that the proper choice of the actuator area is more efficient in reducing deflections/eigenfrequencies. The accuracy of optimal design are verified both with the aid of the FE package ABAQUS and using the standard Rayleigh-Ritz method. The results concerning active vibration control for axisymmetric cylindrical shells are also discussed. 相似文献
9.
压电梁振动的多输入多输出主动控制 总被引:2,自引:1,他引:1
对表面上贴有多个用作驱动器和传感器的压电陶瓷片的“压电梁”结构,导出了从驱动器到传感器的频响函数公式,作为压电结构设计和振动控制的数学模型。提出了压电梁对缓变周期扰动振动环境的多输入多输出振动抑制方法。 相似文献
10.
V. M. Bogomol'nyi 《Measurement Techniques》1997,40(4):391-395
It is shown that one can build field-controlled piezoelectric actuators of flexual type in which the strong steady field produces
polarization uneven in the thickness, while the additional alternating field provides the working diesplacements. Formulas
are given for the general case (ferroelectric ceramic shells) relating the mechanical stresses, the strains, and the external
electric field. The electromechanical bending effect in a cantilever piezoceramic plate is considered in detail for optical
radiation modulators.
Translated from Izmeritel'naya Tekhnika, No. 4, pp. 64–67, April, 1997. 相似文献
11.
Ruan X Cheeseman BA Safari A Danforth SC Chou TW 《IEEE transactions on ultrasonics, ferroelectrics, and frequency control》1999,46(6):1489-1496
This paper reports the conceptual design, analysis, and modeling of the electromechanical behavior of dome actuators. The geometric parameters of the actuator (dome thickness, width, radius, and depth), poling direction, electric field, and material properties (elastic compliance, piezoelectric constants, and dielectric permittivity) have been taken into account in the modeling work. The results of the analysis indicate that a dome actuator with a tangentially alternating poling direction and electric field (Case C) exhibits much larger displacement and force responses than dome actuators with other poling directions and electric fields. The first mode of natural frequency of the Case C dome actuator also was investigated, and its predicted performance was compared with that of moonie and rainbow actuators. The findings of this research clearly demonstrate the merit of design optimization of electromechanical devices. 相似文献
12.
Finite element modeling of active control of functionally graded shells in frequency domain via piezoelectric sensors and actuators 总被引:4,自引:0,他引:4
A flat-shell element is presented for the active control of functionally graded material (FGM) shells through integrated
piezoelectric sensor/actuator layers. The finite element formulation based on first-order shear deformation theory (FSDT)
can be applied to shells ranging from relatively thin to moderately thick dimensions. A constant gain displacement and velocity
feedback control algorithm coupling the direct and inverse piezoelectric effects is applied to provide active control of the
integrated FGM shell in a self-monitoring and self-controlling system. Frequency response characteristics of the FGM shell
containing the piezoelectric sensors/actuators are analyzed in the frequency domain. The effects of constituent volume fraction
and the influence of feedback control gain values on the dynamic responses of the FGM shell system are examined in detail.
Received 13 November 2000 相似文献
13.
Micro actuators are an irreplaceable part of motion control in miniaturized systems and are intended to have a high range of deformation, high accuracy, large force, and quick response. In this article, an analytical model for a hybrid thermopiezoelectric micro actuator is developed in which a double lead-zirconnate-titanate piezoceramic (PZT) beam structure consisting of two arms with different lengths are used. Governing differential equation of motion and electrical field are derived and solved. Out of parametric studies it was observed that, under application of temperature and voltage gradients, the deflection of the actuator shows different trends depending on the geometry of the micro actuator and also type of PZT material. 相似文献
14.
Summary. This paper provides a comprehensive analysis of the two-dimensional wave propagation in an elastic medium induced by embedded
multiple piezoceramic actuators. Based on a new actuator model, which involves the deformation in both the transverse and
longitudinal directions of the actuator, the actuation process and the dynamic load transfer between multiple actuators and
the host medium is studied. The formulation of the problem is established using the analytical solution of the single actuator
problem and a pseudo-incident wave method. Detailed numerical simulation is conducted to study the electroelastic behavior
of this composite system. Attention is focussed on the properties of generated waveforms for different actuator arrangements.
Received March 5, 2002; revised July 24, 2002 Published online: January 16, 2003 相似文献
15.
The last two decades have witnessed the proliferation piezoelectric composite transducers for an array of sensor and actuator
applications. In this article, a concise summary of the major methods used in composite making, with special emphasis on Solid
Freeform Fabrication (SFF), is provided. Fused Deposition of Ceramics (FDC) and Sanders Prototyping (SP) are two SFF techniques
that have been utilized to make a variety of novel piezocomposites with connectivity patterns including (1-3), (3-2), (3-1),
(2-2) and (3-3). The FDC technique has also been used to prototype a number of actuators such as tube arrays, spiral, oval,
telescoping, and monomorph multi-material bending actuators. It has been demonstrated that SFF technology is a viable option
for fabricating piezocomposite sensors and actuators with intricate geometry, unorthodox internal architecture, and complex
symmetry. The salient aspects of processing of such composite sensors and actuators are summarized, and structure-processing-property
relations are elaborated on. 相似文献
16.
Wang QM Du XH Xu B Cross LE 《IEEE transactions on ultrasonics, ferroelectrics, and frequency control》1999,46(3):638-646
Electromechanical coupling mechanisms in piezoelectric bending actuators are discussed in this paper based on the constitutive equations of cantilever bimorph and unimorph actuators. Three actuator characteristic parameters, (e.g., electromechanical coupling coefficient, maximum energy transmission coefficient, and maximum mechanical output energy) are discussed for cantilever bimorph and unimorph actuators. In the case of the bimorph actuator, if the effect of the bonding layer is negligible, these parameters are directly related to the transverse coupling factor lest. In the case of the unimorph actuator, these parameters also depend on the Young's modulus and the thickness of the elastic layer. Maximum values for these parameters can be obtained by choosing proper thickness ratio and Young's modulus ratio of elastic and piezoelectric layers. Calculation results on four unimorph actuators indicate that the use of stiffer elastic material is preferred to increase electromechanical coupling and output mechanical energy in unimorph actuators. 相似文献
17.
Dogan A. Uchino K. Newnham R.E. 《IEEE transactions on ultrasonics, ferroelectrics, and frequency control》1997,44(3):597-605
This paper presents original results obtained in the development of the moonie-type transducers for actuator applications. The moonie-type actuators fill the gap between multilayer and bimorph actuators, but its position-dependent displacement and low generative force are unacceptable for certain applications. The moonie transducers were modified systematically by using finite element analysis combined with experimental techniques. A new transducer design, named “cymbal transducer”, was developed with larger displacement, larger generative forces, and more cost-effective manufacturing. The cymbal transducers consist of a cylindrical ceramic element sandwiched between two truncated conical metal endcaps and can be used as both sensors and actuators. The cymbal actuator exhibits almost 40 times higher displacement than the same size of ceramic element. Effective piezoelectric charge coefficient, Eff. d33, of cymbal is roughly 40 times higher than PZT itself 相似文献
18.
Wei-Hsin Liao Kwong Wah Chan 《IEEE transactions on magnetics》2008,44(4):525-532
Current dual-stage actuator design uses piezoelectric patches only, without passive damping. In this paper, we propose a dual-stage servo system using enhanced active-passive hybrid piezoelectric actuators. Because they incorporate passive damping, the proposed actuators will improve the existing dual-stage actuators, giving them higher precision and better shock resistance. We report finite-element analyses of different types of piezoelectric actuators in a disk arm assembly under external shock and vibration. We modeled the viscoelastic damping layers in the hybrid actuators with the Prony series, whose parameters we determined from the dynamic frequency data of a nomograph. In the analyses, a shock impulse (175 g, 1 ms half sine) and a vibration impulse (350 g and 1 ms full sine) are applied at one end of the base, while the other end of the base is fixed. We evaluated and compared the responses of the disk arm assembly with different configurations of the piezoelectric actuators. The simulation results show that the enhanced active-passive hybrid actuator design would reduce the residual in-plane vibration induced during the shock, resist liftoff motion, and reduce the impact damage when the head slaps. 相似文献
19.
Piezoelectric actuators are spreading their applications in a variety of engineering systems, e.g., a compression mechanism with large force and high-precision motion systems. A systematic investigation of the dynamics of piezoelectric actuators that interact with loading structures is becoming requisite. This article discusses the dynamic model by merging constitutive equations of the piezoelectric material and the dynamics of loading structures. The dynamic behavior of piezoelectric actuators that interacts with loading structures depends on the stiffnesses of both entities. Two of the most common operating conditions of the actuator, based on its interaction with the loading structures, are classified and considered in this study: fixed–free and free–free conditions. The proposed dynamic models are subsequently validated on real mechanisms with satisfactory results. It is shown that the models are capable of capturing the dynamic interaction between the actuators and loading structures. 相似文献
20.
晶体结构对压电陶瓷微位移驱动器特性的影响 总被引:5,自引:0,他引:5
对钙钛矿结构的PZT-5和钨青铜结构的PBNN二种压电陶瓷制成的压电微位移器进行了电压-位移特性的比较和分析,发现我们所研制的PBNN压电微位移器具有线性好、回零好、等优点。 相似文献