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Smart machining has tremendous potential and is becoming one of new generation high value precision manufacturing technologies in line with the advance of Industry 4.0 concepts. This paper presents some innovative design concepts and, in particular, the development of four types of smart cutting tools, including a force-based smart cutting tool, a temperature-based internally-cooled cutting tool, a fast tool servo (FTS) and smart collets for ultraprecision and micro manufacturing purposes. Implementation and application perspectives of these smart cutting tools are explored and discussed particularly for smart machining against a number of industrial application requirements. They are contamination-free machining, machining of tool-wear-prone Si-based infra-red devices and medical applications, high speed micro milling and micro drilling, etc. Furthermore, implementation techniques are presented focusing on: (a) plug-and-produce design principle and the associated smart control algorithms, (b) piezoelectric film and surface acoustic wave transducers to measure cutting forces in process, (c) critical cutting temperature control in real-time machining, (d) in-process calibration through machining trials, (e) FE-based design and analysis of smart cutting tools, and (f) application exemplars on adaptive smart machining.

Numerous developments have been dedicated these passed years to demonstrate the use of surface acoustic wave (SAW) devices as passive sensors probed through a wireless radio-frequency link. Giving access to physical parameter variations without embedded power supply, recent works have shown that SAW sensors can be used under harsh environments such as temperatures in excess of 300 °C and much more. The purpose of this paper is to present a new packaging process for SAW sensors operating under temperature environments up to 600 °C. The robustness of this packaging process is first validated at the above-mentioned temperature using a classical temperature probe via wired connection. The reliability of this process applied to differential SAW sensors then is demonstrated by wireless interrogation of a quartz-based SAW differential sensor from room temperature to 480 °C. The sensor operation has been validated for several tens of hours without major failure nor significant deviation, although the measurement distance dynamic range is observed to be dramatically reduced with operating on such a wide temperature range.

The present paper describes single-phase unidirectional transducers (SPUDT) cells with all fingers wider than A/S while maintaining the unidirectional effect. The first solution is related to a SPUDT consisting of /spl lambda//4 and /spl lambda//2 wide fingers arranged in two tracks. Each track has no significant unidirectional effect. Both tracks form a wave-guide, and the waveguide coupling generates the interaction of the tracks. As a result of that interaction, a unidirectional effect arises as verified by experiment. This transducer type is called double-track (DT) SPUDT. A second solution is suggested that includes, in contrast to distributed acoustic reflection transducer (DART), electrode width control (EWC), and Hunsinger cells, SPUDT cell fingers with one and the same width only. Cell types with /spl lambda//6, /spl lambda//5, and /spl lambda//3 wide fingers called uniform width electrode (UWE) cells are considered. One of these cell types, including exclusively /spl lambda//5 wide fingers, is experimentally investigated and a unidirectional effect is found. Moreover, a filter example using the /spl lambda//5 cell type has been designed for reducing SPUDT reflections. The echo suppression expected could be verified experimentally. No wavegiiide coupling is required for this cell type.

This review paper focuses on interdigital electrodes-a geometric structure encountered in a wide variety of sensor and transducer designs. Physical and chemical principles behind the operation of these devices vary so much across different fields of science and technology that the common features present in all devices are often overlooked. This paper attempts to bring under one umbrella capacitive, inductive, dielectric, piezoacoustic, chemical, biological, and microelectromechanical interdigital sensors and transducers. The paper also provides historical perspective, discusses fabrication techniques, modeling of sensor parameters, application examples, and directions of future research.

A theoretical analysis for the surface-acoustic-wave-based wireless transponder in a wireless system has been proposed in this paper. Radio transponders were also implemented based upon the theory of coupling of modes. The proposed theory can be employed in the simulation of amplitude- and phase-coded devices with different segments,.

The Green's function method is generally agreed to be the most satisfactory technique for the rigorous analysis of surface-acoustic-wave interdigital transducers (IDTs). However, its direct application to response investigations or optimization-based design activities is limited by its computational complexity. In this paper, we present a new reduced-order model of IDTs based on a moment-matching technique and on the singular value decomposition. Several numerical and experimental examples demonstrate the accuracy and the efficiency of the method.

Surface acoustic wave (SAW) generation on 128° YX acoustic superlattice has been investigated by considering the finite-depth of the domain created by the UV direct-domain writing. We found that bound and localized SAW will be generated when the domain depth of the ASL structure, underlying the transducer, is smaller and bigger than the lattice period, respectively. Efficient bound SAW can be achieved, provided the domain depth is 30% of the lattice period.

International audience; The constant improvement of industrial needs to face modern telecommunication challenges leads to the development of novel transducer principles as alternatives to SAW and BAW solutions. The main technological limits of SAW (short-circuit between electrodes) and BAW (precise thickness control) solutions can be overcome by a new kind of transducer based on periodically poled ferroelectric substrate. The approach proposed in this paper exploits a ridge structure combined with a periodically poled transducer (PPT), allowing for the excitation of highly coupled modes unlike previously published results on planar PPTs. High-aspect-ratio ridges showing micrometer dimensions are achieved by dicing PPT plates with a diamond-tipped saw. An adapted metallization is achieved to excite acoustic modes exhibiting electromechanical coupling in excess of 15% with phase velocities up to 10 000 m*s-1. Theoretical predictions show that these figures may reach values up to 20% and 18 000 m*s-1, respectively, using an appropriate design.

International audience; A linear frequency modulated transducer was earlier proposed for use in surface acoustic wave (SAW) tags and sensors. This reported work demonstrates that the hyperbolically frequency modulated (HFM) transducer has significant advantages for such devices often operating in a wide range of temperatures. The HFM transducer is practically insensitive to wide temperature variations, which expand or compress signals in time. Owing to the exponential change of the varying period with the electrode number, the expansion of the length of all the periods is equivalent to just a shift in time and the compressed signal remains practically unchanged in shape, just slightly shifted. Such a shift has no importance for SAW sensors/tags, which usually operate on the difference of delays of the compressed peaks.

International audience; Packageless heterostructure AlN/IDT/AlN/Sapphire was investigated as a solution protection of the interdigital transducer against agglomeration phenomena at high temperature. For this purpose, the performance of conventional IDT/AlN/Sapphire and protected AlN/IDT/AlN/Sapphire heterostructures were compared. The capability of AlN protective thin film to minimize the deterioration of electrodes was shown.

This paper reports an improvement of miniaturized six-component odor blender using electroosmotic (EO) pumps and a surface acoustic wave (SAW) device. Tiny droplets of liquid odor samples spouted from EO pumps were atomized by SAW atomizer into odorant vapors to generate smells rapidly even the scents of low volatile substances which typically requires much time to release. The device works soundlessly, does not produce heat to the nearby environment, and is more robust against bubble comparing with an olfactory display composed of the widely used inkjet devices. In this research, a quartz crystal microbalance (QCM) gas sensor was used to measure the intensities of generated odor vapors. As a result, the capability to blend up to three odor components was confirmed.

We demonstrate the operation of surface-acoustic-wave (SAW) transducers fabricated on AlN/SiC structures at frequencies as high as 19 GHz. The high SAW velocity of the AlN film is enhanced by the even higher sound velocity of the SiC substrate, enabling us to achieve these frequencies with a SAW wavelength of 400 nm.

International audience; We show that an appropriate mass-loading, placed on the surface and in between the electrodes of a coplanar acoustic LiNbO3 superlattice, can counteract lateral diffraction of surface acoustic waves (SAWs). The strong confinement corresponds to a SAW mode, whose displacement is measured using laser interferometry. The proposed SAW confinement method has also potentials in acousto-optic devices, as we demonstrate a threefold reduction in the electrical power required for complete optical switching in mass-loaded superlattice with respect to similar unloaded structure. The devices have also the advantage not to suffer additional acoustic or optical loss due to the mass-loading structure.

SPUDT cells including two fingers only are hitherto known for so-called NSPUDT directions. In this case, usual solid-finger cells are used. The purpose of the present paper is to find SPUDT cell types consisting of two fingers only for pure mode directions. Moreover, SPUDT cells composed of two fingers suited to complete imperfect NSPUDT behavior or to compensate that are to be found. TF cells for pure mode directions on substrates like 128degYX LiNbO3, YZ LiNbO3 and STX quartz were found by means of an optimization procedure. The forward direction of a TF-cell SPUDT on 128degYX LiNbO3 was determined experimentally. The properties of the new cells are compared with those of conventional SPUDT cells. The reflectivity of TF cells on 128degYX LiNbO3 turns out to be two up to three times larger than that of DART and Hanma-Hunsinger cells at the same metal layer thickness. Furthermore, properties of TF cells on STX and SST quartz are reported. Examples for completing and compensating imperfect NSPUDT behavior are given.

Process Compensated Resonant Testing (PCRT) has been demonstrated as an excellent alternative for ceramic parts, going beyond traditional resonance testing by applying pattern recognition algorithms and process control statistics to precise resonant data. PCRT is used for studying structural integrity and functional performance in a variety of ceramic parts. PCRT is a whole body inspection that detects internal defects such as cracks, voids, and inclusions. PCRT can also perform surface inspection of balls, using Surface Acoustical Waves. PCRT can be performed in real manufacturing time, and computer control eliminates operator error and subjectivity.

In this paper, we incorporate two thermal models with periodic FEM/BEM to analyze the temperature-frequency behavior of SAW under periodic IDT. One is the classical model based on Campbell's theory, which has been widely used. We find that this model fails to predict temperature-frequency behavior of SAW for some cases, although we can get accurate results for many cases of some cuts and modes by using this model. The other is based on piezoelectric, Lagrangian equations. This one his proved to be a general model for the analysis of thermal effects on SAW, and is more accurate than the first one. But the application of this model is limited to quartz-based devices, because the temperature coefficients of material constants for other materials for piezoelectric, Lagrangian equations are not available at present. In practice, the two models are useful for the designing of SAW devices.

In this paper we present new polyurethaneimide (PUI) copolymers SO 2 as sensitive layers for a gas sensor based on a ZnO/Quartz ST-90 SAW transducer. These copolymers, which contain tertiary amine groups acting as Lewis bases, were characterized by Brillouin spectroscopy in order to determine the optimal sensor parameters. Gas sensors consisting of trilayer structures PUI/ZnO/Quartz were then developed successfully and tested under SO 2 with the different PUI copolymers. The observed sensor responses are discussed in terms of structure-properties relationships.

In this work, we propose a new 2D bi-periodic transducer fabricated on single crystal susbtrates allowing for complex wave polarization excitation. The structure has been theoretically analysed using a mixed finite element/boundary element approach, showing numerous acoustic-electric contribution on the harmonic admittance for quartz. An experimental device then has been built on LiNbO3 using SiO2 spacers for 2D interconnection purpose. The device has been tested successfully, allowing for a first demonstration of the transduction principle. More work now will be achieve to better understand the transducer operation and to propose actual application of this 2D transducer.

For dielectric constants, only e13 was significantly changed during correction prosess. This is because e13 is small and have low influence on to capacitance. Mostly changed elastic constants are s12 and s23. Such a big change is due to low accuracy for these constants in resonance-antiresonance method. A mean for other constants change is about 6 %. Mostly changed piezoelectric constants are d31 and d32. Differences between measured and calculated SAW parameters are lower for corrected material constants.

We demonstrate a microfabricated 63Ni radioisotope-powered RFID transponder realized with a SAW (surface acoustic wave) device as the transmission frequency selector. The transponder is powered by a 1.5 milli-Ci 63Ni source which has a half-life of 100 years. We have achieved a 5mW, 10-µs long, 100MHz carrier envelope, RF pulses which occur every 3 minutes, across a 50Ω load. The transponder can potentially work autonomously for decades, which can revolutionize long term reliable sensing and monitoring.

A use of self-matched unidirectional transducers (SMUDTs) is proposed in application to SAW tags. SMUDT provides simultaneously both high degree of its directionality and matching with the tag antenna without additional external circuitry. Numerical simulations of the tags, synthesized on 128° YX-LiNbO 3 , confirm an efficiency of the proposed technique.

The design and testing of 4 channels switchable low loss SAW filter bank with SAW notch filters is described. Slanted-finger interdigital transducer (SIDT) including EWC/SPUDT is adopted to achieve the low insertion loss of individual SAW filter. SAW filters are fabricated on YZ LiNbO3 substrate with the insertion loss of less than 6.5 dB, the stop-band rejection of more than 40 dB, the 1 dB bandwidth of more than 9 MHz and the 40 dB bandwidth of less than 15 MHz. Switches are added to both input and output of SAW filters and two SAW notch filters are separately connected to the input and output of the switches. SAW notch filters are fabricated on Y36deg LiTaO3 substrate with the rejection of more than 30 dB and the insertion loss of less than 0.5 dB. The experimental filter bank results in the insertion loss of 7.5 dB, the stop-band rejection of more than 40 dB, and the rejection more than 60 dB at the frequency through the stop-band of the SAW notch filter.

This paper presents a new approximate method for analyzing reflective SAW transducers, with much of the convenience of the coupled-mode (COM) method but with better accuracy. Transduction accuracy is obtained by incorporating the accurate electrostatic solution, giving for example correct harmonics, and allowance for electrode width variation, in a simple manner. Results are shown for a single-electrode transducer, Natural SPUDT and DART SPUDT, each using theoretically derived parameters. In contrast to the COM, the RAM can give accurate results for short or withdrawal-weighted transducers and for wide analysis bandwidth.

Dispersion curves for Langasite (0deg, 140deg, 26deg) are calculated by modified FEMSDA program. All the basic COM parameters are extracted from calculated dispersion curves. In particular, the phase velocity in the center of the stopband, reflectivity, transduction coefficient per electrode and directionality are determined for 0.1

The advantages of langasite as a substrate material for SAW filters are not realized entirely till now because of the natural unidirectivity of most cuts available for practical applications. This paper presents new results that allow the utilization of langasite for SAW filters. The mathematic model, SPUDT cell structures and design method were developed for naturally unidirectional orientations. This approach allows designs of slanted and RSPUDT filters on yxlt/48.5726.6deg langasite with 7 dB - 10 dB insertion losses and bandwidths 1% - 3%.

One of the important properties of the SAW transducer is the sensitivity to the external acting quantities. This sensitivity depends both on the strain and relative SAW velocity change due to the external, namely electric fields. The basic equations describing both contributions are presented in the paper. The resulting relative frequency change of the SAW transducer is the result of the strain due to the dimensions changes and the relative SAW velocity change due to the non-linear effects. The configuration of the oriented substrate (may be with domain wall), and the equations describing an influence of the electric field are described. Both the SC-cut quartz-and LiNbO3 substrates are discussed considered in this paper. The principle or new configuration may be used for SAW applications.

In this work, the singular behavior of the charges at corners and edges of the 3D electrodes-bus system are investigated. These considerations are then used for the definition of a hybrid element model of SAW transducers

A periodic cell of the floating electrode unidirectional SAW transducer (FEUDT) in the general case of electrodes of finite thickness and of different width is investigated. The important parameter of unidirectionality as a phase shift between reflection and transduction centers is calculated. In contrast to the regular case of equal width electrodes and gaps, one can see a lot of possibilities to reach the optimal phase shift 45/spl deg/.

Formulas are derived for the P-matrix of a cascade of identical acoustic transducers, in terms of the P-matrix of one elementary transducer. The derivation makes no assumptions other than reciprocity and the validity of the P-matrix description. Consequently, the results are valid for a wide range of cases, such as simple SAW gratings or group-type single-phase unidirectional transducers (SPUDT's), where each element is a transducer plus grating. The formulas are used to derive a general relation for the directivity of a SPUDT in terms of the directivity of one period.

A SPUDT structure employing /spl lambda//4 and wider electrodes is introduced. The design and its variants exploit the significant difference between the reflectivity of short-circuited /spl lambda//4 electrodes and that of floating wide electrodes on 128/spl deg/ LiNbO/sub 3/. The SAW devices operating at 2.45 GHz have critical dimensions of about 0.4 /spl mu/m, accessible for standard optical lithography. When matched, the fabricated SPUDT filters exhibit minimum insertion losses of 5.5-7.9 dB together with 3 dB pass-bands of 95-102 MHz.

A new single track structure for this unidirectional quadrature IDT coupler has been proposed to reduce a device size. Advantages of the device size and bandwidth for this structure are verified by the calculations and the experiments. The double mode IDTs structure on X-112/spl deg/Y LiTaO/sub 3/ and 190 MHz center frequency are chosen for the experiment.