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A new concept is needed in designing and processing of nanostructured ceramic-polymer composites to respond to all technological requirements related to 3D-printing technology for obtaining innovative flexible piezo-electric harvesters. A technique for obtaining of thermoplastic composites with piezoelectric features is presented.

For several decades, research has been conducted for total ankle replacement to be established as the optimal surgical treatment for diseased or degenerative ankle joints. Few reports exist regarding computer assisted surgery (CAS) and patient specific instrumentation for total ankle replacement (TAR), but no studies regarding instrumented ankle prostheses capable of obtaining stress distribution data or related works using sensing technology for improving patient specific instrumentation exist. In this paper, finite element simulations of a thin film piezo electric sensor for obtaining the pressure map of the contact surface are presented. The pressure map would provide potential benefits for component alignment and enhance TAR final outcomes.

When a person walks, pressure is exerted on the ground and this pressure can be converted into electrical energy and it can be used to power electronic devices. In this paper a Mobile charging system is designed. A piezo electric generator is placed in the shoe. The power that is generated by piezo electric generator when a person walks is transferred to the device by using a mid-range wireless power transfer (WPT) which is a Resonance coupling technique.

In this paper, we report three new results. 1) We show simulations of max output power from a Piezo-Electric (PZ) Energy Harvesting Device (EHD) as a function of frequency and Bias Flip (BF) efficiency. These simulations show that BF with 95% efficiency improves the 3dB BW by 4x. They also show that, at frequencies 30% above resonance (150 Hz) or below resonance (80 Hz), 95% BF efficiency improves output power by >15x (13.6 dB) compared to the case of no BF. 2) We experimentally demonstrate that 95% BF can be achieved on non-Piezo-Electric (non-PZ) capacitors. 3) We show that BF efficiency on PZ capacitors is lower than for non-PZ capacitors, and we relate this to the series resistance of the EHD at the BF frequency.

Pulse-echo system is the most widely used equipment in non-destructive testing (NDT). Herein we present the SPICE implementation of a piezo-electric transducer for pulse-echo system. The SPICE model has been developed with an intention to obtain a virtual instrument for the pulse-echo system. The SPICE implementation of pulse-echo system includes the lossless piezoelectric transducer as an actuator and the sensor. The output of actuating stage is fed into the sensing stage of the sensor stage. The simulated results in the actuation and sensing modes are compared to the previously reported experimental results and the output trends are in good agreement. Findings from the comparative study, validate the application of our proposed model as a virtual system for pulse-echo system for non-destructive testing.

This paper reports the design, fabrication and characterization of an inter-digitated piezoelectric actuation mechanism for micro-lens movement. A theoretical model has been developed and substantiated by ANSYS simulation. Results show good agreement with both simulation and modeling. The out-of-plane deflection is 24µm at 6V/µm electric field with a maximum Deflection Sensitivity to Voltage (DSV) of 0.5µm/V. The unloaded resonance frequency is 2420Hz. With a 600µm diameter ball lens weighing 320µg mounted to the actuation structure, the resonance frequency is reduced to 752Hz without significantly impacting the static out-of-plane deflection behavior. In comparison to other micro-lens actuator, this structure demonstrates large deflection response and a relatively large resonance frequency.

In this paper, the effective XRD profile factors for the improvement of piezoelectric characteristic especially for BaTiO 3 well known as unleaded piezoelectric material were specified by analysis software RIETAN-2000, under the conditions based on literature review by other research groups such as the improvement of piezoelectric property due to the increase of the crystallite size, the decrease of lattice strain for the piezoelectric material, and the decrease of half value width for X-ray diffraction pattern improving the crystalline. As a result, it was clear that a decrease in the isotropic lattice strain was effective to show high piezoelectricity.

The piezo-actuated XY-table is composed of two piezo electric actuators (PEA) and a positioning mechanism (PM). Due to existence of hysteretic nonlinearity in the PEA and the friction in the PM, the high precision control for the XY-table is a challenging task. This paper discusses the high precision adaptive control for the XY-table, where the hysteresis is described by Prandtl-Ishlinskii model. The proposed control law ensures the global stability of the controlled stage, and the position error can be controlled to approach to zero asymptotically. Experimental results show the effectiveness of the proposed method.

The current paper presents a combined structure of wind direction and speed sensor that has simple and compact construction with no moving parts. The sensor utilizes thin film PVDF piezo electric strips. Its suggested advantages can be utilized to improve weather measurements relevant to various renewable energy generators.

The XY-table is composed of two piezo electric actuators (PEA) and a positioning mechanism (PM). Due to existence of hysteretic nonlinearity in the PEA and the friction in the PM, the high precision control for the XY-table is a challenging task. This paper discusses the high precision adaptive control for the XY-table, where the hysteresis is described by Prandtl-Ishlinskii model. The proposed control law ensures the global stability of the controlled stage, and the position error can be controlled to approach to zero asymptotically. Experimental results show the effectiveness of the proposed method.

This paper outlines the operation principles with the piezo electric sensors for airport surface movement control. This type of sensor enables one not only to essentially reduce power consumption to a level acceptable by sustainable sensor network, but also to perform moving object detection on voltage impulse created by pressure from moving objects, as well as to perform automatic classification of objects according to their weights, speed and direction of movement. The preliminary result of experimental tests on piezo thin film sensor, which is light weight and bears similar physical properties as piezo electric sensor, confirms the predicted operation characteristics, and shows the applicability of piezo electric sensors for monitoring airport surface movement.

In turning, the self-excited vibration, also called chatter, is undesirable as it gives rise to production problems. In this paper, in order to suppress chatter in turning, a turning process is modeled as a two degree-of-freedom uncertain system. A piezoactuator, the structure of which is independent of the tool holder in the machine, is introduced for the regulation of the cutting tool displacement. An adaptive control law is proposed and the simulation results show that the proposed adaptive control law significantly eliminates the chatter phenomena.

Piezoelectric AlN and PbZr/sub x/Ti/sub 1-x/O/sub 3/ (PZT) layers are investigated with respect to their potential for HF micro-electronic applications. High quality AlN films with strong c-axis orientation are achieved by optimum deposition conditions and by applying nucleation layers. Electromechanical coupling factors of 0.25/spl plusmn/0.03 have been found. PZT films grown via sol-gel processing show high coupling factors k of 0.4-0.6 and are therefore attractive for wide bandwidth applications.

Bone is now a well established piezo-electric material. This property is used to develop a dynamic sensor for biomedical measurements, particularly to study the bone conditioning, under vibration. The sensor is found to work efficiently in the frequency range of 0.5 KHz to 50 KHz with the advantages of low cost and ease of fabrication. It has been tested in acoustic transmission studies of the bone to detect a fracture, its union and rate of healing.

The fraud protection currently provided by the personal identification number (PIN) is not always sufficient. Automatic verification of signatures at points of sale or bank terminals can improve this protection. Dynamic characteristics involved in writing a signature are difficult to forge but usually require specially wired pens, not suitable for hard day-to-day use. A low-cost piezoelectric film underneath a writing surface can detect stylus position and velocity profiles, thus permitting verification of the signature using both static and dynamic features. Arrays or parallel electrodes detect pen velocity profiles without being affected by touching fingers or by noise. >

A new electronic controlled suspension system called Piezo TEMS (Toyota electronic modulated suspension) is developed by using piezoelectric ceramics for a sensor, and an actuator. As a result, good drivability and vehicle stability can be obtained with an improved riding comfort. >

A miniaturized chopper for fiber optical multimode applications has been developed at the Institut fur Mikrostrukturtechnik at Forschungszentrum Karlsruhe. Transmittance is modulated by a piezo electric driven shutter, moving in a gap between two multimode fibers.

For the same aperture the focal zone of the electrohydraulic generator is much larger than the piezoelectric one. In a previous work we shown that the focal zone obtained with the same generator but where the inter space of the electrodes is filled with an electrolyte instead of water was 100 times lower and approximatively equal to the piezoelectric focal zone. So we think that the conventional electrohydraulic generator does not work well. Some measurements made using ombroscopy, film and triangulation confirm that the plasma formation takes place not always exactly at the first foci. After measuring the pressure in function of the off axis we conclude that the plasma formation is responsable of the large focal zone of the conventional electrohydraulic generator.

Some mixed or sensorineural hearing losses currently depend on conventional hearing aids. But during the last 5 years hearing aids implanted in the middle ear have been under study. Using a piezo-electric transducer, an animal model in guinea pig was developped. Chronic and acute experimentations were realised. With piezo-eletric tansducer chronically implanted, thresholds for click evoqued action potentials of the auditory nerve required electric level of about 100 mV. The vibrator was well tolerated. Then other positions of the vibrator were tested during acute experimentations. It appears that the best place to put the vibrator is on the ossicular chain. These results confirm other sudies from Yanagihara and all.

The design, construction and operation of a deep towed bottom profiling system is described, capable of high resolution depth sounding and subbottom profiling in water depths in excess of 1000 feet. The system uses both sequentially operated spark and piezo electric sources, information is transmitted to the surface through a multiconductor instrument cable. The effects of pressure on conventional spark sources are discussed. Operational techniques are discussed. Sample profiles from various depths and locations illustrate system performance.