Piezo Device Research Articles

Effects of corrugation on convective heat transfer and power generation in a wavy walled triangular cavity equipped with inclined elastic fin and piezo-energy harvester assembly

Piezoelectric energy harvesters are one of the energy conversion technologies that can be used to convert a variety of external sources, including wind, fluid motion, and vibrations, into electrical energy. This work suggests a novel wall corrugation design in addition to an elastic fin piezo assembly arrangement for power generation and thermal management in a triangular cavity during turbulent forced convection of air. Using the finite element method with ALE, the analysis is conducted for different values of fin inclination (γ between 0 and 60), corrugation amplitude (Af between 0.01H and 0.06H), corrugation frequency (Nf between 1 and 20) and fin distance from the mid-point of the inclined wall in wall direction. The average Nusselt number (Nu) and generated power (PW) show a non-linear increasing trend with increasing fin tilt. Average Nu increment factor becomes 5.17 with the highest fin inclination while the power increments become 11.6 and 4.46 when rising inclination from 30 to 45 and from 45 to 60. The generated power rises with higher corrugation amplitude and wave number. However, increasing the wave number results in thermal performance degradation. Increment of average Nu becomes 1.17 with highest corrugation amplitude while it declines by a factor of 10.3 at the highest wave number. Power enhancement factors of 5.73 and 2.32 are obtained by increasing the corrugation amplitude from Af = 0.0714H to Af = 0.1786H and from Af = 0.1786H to Af = 0.2143H. When fin positions sf = 0.7143H and sf = -0.7143H are compared with the case of fin location at sf = 0, the power increment factors become 12.27 and 4.76, respectively. For the power produced by the piezo device, a polynomial type correlation is suggested by adjusting the parameters of the corrugated wall.

Harvesting and Shaping of Ossified Costal Cartilage with Piezo Device in Rhinoplasty

Harvesting and Shaping of Ossified Costal Cartilage with Piezo Device in Rhinoplasty

Modeling of Strain Actuation on Relatively Soft Curved Beams by Piezoelectric Ceramics for De-Icing Systems

In this work, the effects of some geometric and mechanical parameters that characterize curved and relatively soft structures integrated with piezoelectric actuators are investigated. The effect of parameters such as the curvature, location, and extension of the piezo device, as well as the thickness of the bonding and its strength, are considered in view of a potentially lighter model that replaces the piezoelectric device via its actions, namely pin forces, whose layout and values are strongly dependent on the curvature. When comparing the results obtained by a finite element model of the structure with the piezo device and of the structure alone under the action of pin forces, dedicated indicators were found, which could be useful to support lighter modeling approaches and to predict the authority of the piezoelectric device.

TREATMENT OF MEDICATION-RELATED OSTEONECROSIS OF THE JAWS WITH ULTRASONIC PIEZOELETRIC BONE SURGERY AND OXYGEN THERAPY: A CASE REPORT

A 65-year-old femal patient complained mainly of "an exposed bone that appeared after tooth extractions performed eight months earlier". Her medical history revealed breast cancer and lung metastasis, undergoing treatment with chemotherapy, radiotherapy, and Zoledronate. Intraoral examination revealed necrotic bone in the mandible with the presence of exudate. Panoramic radiographs demonstrated evidence of a radiopaque image, suggestive of bone necrosis involving the region of lower incisors and extensive area of bone sequestration spread across the body of the mandible to the region of pre-molars. Treatment included 0.12% chlorhexidine digluconate mouth rinses, antibiotic therapy, laser therapy, and hyperbaric oxygen therapy before and after surgery. Surgery was performed using vibrating tips connected to a high power ultrasonic (piezo) device, and the necrotic bone which was sent for histological analysis. The patient received followed up for two years, presenting good general health and no sign of bone exposure. A 65-year-old femal patient complained mainly of "an exposed bone that appeared after tooth extractions performed eight months earlier". Her medical history revealed breast cancer and lung metastasis, undergoing treatment with chemotherapy, radiotherapy, and Zoledronate. Intraoral examination revealed necrotic bone in the mandible with the presence of exudate. Panoramic radiographs demonstrated evidence of a radiopaque image, suggestive of bone necrosis involving the region of lower incisors and extensive area of bone sequestration spread across the body of the mandible to the region of pre-molars. Treatment included 0.12% chlorhexidine digluconate mouth rinses, antibiotic therapy, laser therapy, and hyperbaric oxygen therapy before and after surgery. Surgery was performed using vibrating tips connected to a high power ultrasonic (piezo) device, and the necrotic bone which was sent for histological analysis. The patient received followed up for two years, presenting good general health and no sign of bone exposure.

Mobile Bony Cap (Meysem Yorgun Technique): An Innovative Technique in Preservation Rhinoplasty for Crooked Nose Deformity.

This study included 25 patients with I- or C-shaped crooked nose deformities who underwent correction with a closed-approach let-down procedure. In this technique, the middle vault is preserved, the bony cap is mobilized and preserved, and the lateral nasal bones are equalized by a piezo device or classical osteotomes. By the mobilization of the bony cap, tension on the dorsal septum is released, and slight asymmetries are hidden behind this mobile bony cap. The postoperative angles for both type I and C deformities were closer to the ideal angle, and the difference was statistically significant. All patients were satisfied with their aesthetic and functional results. In this procedure, we correct asymmetries at the lower maxillary nasal junction, such as in the let-down approach, as well as asymmetries at the K-point, such as in the structural approach. Thus, we combine the advantages of both techniques. Additionally, the mobile-bony cap left on the patient is very useful for releasing the tension of the septal dorsum and hiding slight asymmetries that remain below in the patients.

Evaluation of role of piezo-surgical in mandibular impacted third molar removal

Aim: The purpose of the present research was to assess the role of piezo-surgical and its effectiveness against conventional techniques for removal of impacted mandibular third molar. Methodology: Study included 16 patients (8 male and 8 female) age 17 to 32 years treated in the period from 2019 to 2021. All patients had both mandibular molars impacted. One third molar was extracted using classical technique while the other one using a piezo device. Preoperative preparation was the same for all patients and included radiological analysis and verification of teeth by ortopan tomography (OPG) and CT. Patients were assessed one, seven and 14 days after the procedure. Results: After the extraction, all patients were followed for postoperative symptoms: pain, swelling and paraesthesia of the inferior alveolar nerve. The results confirmed advantages of piezosurgery in the removal of impacted mandibular third molars. Average duration of the intervention was 18 minutes with standard technique while the duration with piezo technique was 23 minutes. According to the visual-analogue scale (VAS) the average pain in the standard group was 9 whereas in the piezo group it was 6.

Drainage tube use for the reduction of postoperative ecchymosis in rhinoplasty

Postoperative healing after rhinoplasty can have a negative impact on patient quality of life. In our study, we aimed to reduce postoperative edema and ecchymosis by applying a minidrain system. We evaluated this intervention's benefit on postoperative morbidity by observing the patient with left and right sides, intervention side and control side respectively. All surgeries were performed using a piezo device with an open technique septorhinoplasty. We only used a left-sided minidrain system through the osteotomy lines just in front of the piriform aperture for all patients with no other intervention on the right side of the same patient. Use of a drain on the left side was associated with a statistically significant decrease in ecchymosis at postoperative day 7 (P<0.05). We found that using a minidrain system through internal osteotomy lines was effective in reducing the amount of ecchymosis by day seven after surgery.

Comparison of the effects of different instrumentation techniques on root surface roughness and cement loss using micro-computerized tomography: An in-vitro study.

The purpose of this study was to compare the effectiveness of three different instruments on the cement loss and roughness of the root surface following scaling and root planning (SRP) using micro-computerized tomography (micro-CT). In this experimental study, 60single-rooted extracted human teeth were used and divided into three groups. All teeth were scanned with micro-CT before and after SRP. Group 1: SRP was performed by Gracey-curette, Group 2: SRP was performed by using an ultrasonic device and Group 3: SRP was performed by using a piezo ultrasonic device. Cement loss and porosity of the root surface were analysed by micro-computerized tomography, which is a current imaging technique that provides high-quality images and allows for qualitative and quantitative analysis of samples. Results of our study revealed that initial porosity values were 1.60%, 1.25%, 1.59% for the group 1, 2, 3, and 0.93%, 0.86 and 0.80 after SRP respectively. Although Group 3had the least surface roughness, there was no statistically significant difference between the groups. Cement loss following SRP was 47.15μmin the piezo ultrasonic device group, 59.44µm in the ultrasonic device, and 134.163µm in the Gracey-curette group respectively. The highest cement loss was seen in the Gracey-curette group, and there was a significant difference between the three groups. In conclusion, it was observed that surface roughness decreased and similar surface roughness was obtained with all three methods, but more cementum loss was observed with Gracey-curette. Therefore, ultrasonic devices appear to be a viable alternative to manual instrumentation with curettes.

High-Level Software Interface to the LLRF System Developed for the European Spallation Source Facility

The European Spallation Source (ESS) accelerator is composed of superconducting elliptical cavities. When the facility is running, the cavities are fed with an electric field from klystrons. Parameters of this field are monitored and controlled by the low-level radio frequency (LLRF) system. Its main goal is to keep the amplitude and phase at a given set point. The LLRF system is also responsible for the reference clock distribution. During operation, the cavities are periodically experiencing strain caused by the Lorentz force, while the high gradient of the electric field is generated for the beam acceleration. Even small changes in the physical dimensions of a cavity shift its resonance frequency. This phenomenon, called detuning, causes significant power losses. It is actively compensated by the LLRF control system, which can physically tune lengths of the accelerating cavities with stepper motors (slow, coarse-grained control) and piezo elements (active compensation during operation). This article describes the implementation and tests of the software supporting various aspects of the LLRF system and cavities management. The Piezo Driver management and monitoring tool is dedicated to a piezo controller device. The LO distribution application is responsible for configuration of the local oscillator. The cavity simulator tool was designed to provide access to properties of the hardware device, emulating behavior of the elliptical cavities. IPMI Manager Software was implemented to monitor the state of MicroTCA.4 crates, which are a major part of the LLRF system architecture. All applications have been created using the experimental physics and industrial control system (EPICS) framework and built in the ESS EPICS Environment (E3).

Estimation of Lorentz force detuning and its compensation on 650 MHz βg = 0.92 single cell SCRF cavity

Superconducting technologies are widely used in modern radiofrequency (RF) cavities for particle accelerators in various fields of applications. The Superconducting radiofrequency (SCRF) cavities are highly sensitive to small perturbation on cavity dimensions. The operation of the superconducting cavity becomes challenging due to narrow resonance bandwidth on account of a very high-quality factor. The main perturbing source is Lorentz Force acting on the cavity wall, which detunes the cavity from resonance. Finite element (FE) analysis has an important role in Lorentz force detuning (LFD) estimation, which requires coupled-field FE analysis between the structural and RF domains of the cavity. The LFD effect can be mitigated up to a certain extent by using a proper fast tuning methodology. This paper represents the methodology for structural-high frequency electromagnetic coupled field simulation for LFD calculation of 650MHz, βg = 0.92 single-cell SCRF cavity. First, the static LFD is calculated for various voltage gradients of SCRF cavity structure and then dynamic behavior of cavity due to LFD pressure pulse is studied at different pulse widths (PW) and pulse repetition rates (PRR). A comparison of transient FE analysis of the single-cell cavity with one end fixed and another end free and cantilever beam for similar loading is done for benchmarking. To counter the detuning effect, the SCRF cavity employs a piezo tuning device. The dynamic behavior of piezo pulse response on the cavity is also studied. An experimental test of the piezo tuner system has been performed at room temperature to validate the FE coupled simulation. Further, dynamic analysis has been carried for the combined effect of LFD pressure and piezo load pulse to compensate for the LFD effect. Optimizing the piezo load for compensating the frequency shift is also discussed and based on optimum load, LFD has been mitigated for different acceleration gradients.

Time Control Nebulizer Operation Using Fuzzy Sugeno Method

Nebulizer is one of the electro medic devices that serve to provide therapy for patients who experience abnormalities or disorders of the respiratory tract. Nebulizer system works using piezo electronic device to produces high frequency vibration. With this high frequency vibration the drug liquid molecules breaks down become fumes, thus it can easily to inhale for patient even for children. Unfortunately like other aerosol drug delivery system, the operation of nebulizer is also still manual. The patient doesn’t really know when the drug is empty on the canister. The nurses also need to check in regularly to see if the drugs are empty or not. In this paper a fuzzy sugeno methods is used to give prediction of nebulizer time operational. We propose fuzzy sugeno to calculate the time operational nebulizer using two parameters, such as drug droplet size and drug liquid volumes that have been administer by nurses. Using fuzzy sugeno method we can solve the nebulizer manual operational time problem. Our result show that the longest operational time was 26.07 minutes, this achieve when liquid volume was 5 ml and the size of drug droplet was 1 um. Meanwhile for the shortest operational time was 8.07 minutes, this achieve when liquid volume was 10 ml and the size of drug droplet was 4 um. We can conclude that we had successful to control nebulizer operational time using fuzzy sugeno method.

Momentum dependent d_{xz/yz} band splitting in LaFeAsO

The nematic phase in iron based superconductors (IBSs) has attracted attention with a notion that it may provide important clue to the superconductivity. A series of angle-resolved photoemission spectroscopy (ARPES) studies were performed to understand the origin of the nematic phase. However, there is lack of ARPES study on LaFeAsO nematic phase. Here, we report the results of ARPES studies of the nematic phase in LaFeAsO. Degeneracy breaking between the d_{xz} and d_{yz} hole bands near the Gamma and M point is observed in the nematic phase. Different temperature dependent band splitting behaviors are observed at the Gamma and M points. The energy of the band splitting near the M point decreases as the temperature decreases while it has little temperature dependence near the Gamma point. The nematic nature of the band shift near the M point is confirmed through a detwin experiment using a piezo device. Since a momentum dependent splitting behavior has been observed in other iron based superconductors, our observation confirms that the behavior is a universal one among iron based superconductors.

Growth of ultrafast, super dense ZnO nanorods using microwaves for piezoelectric MEMS applications

We report a successful integration of a crystalline ZnO thin film with nanorod morphology into a piezoelectric MEMS device. We grow ZnO nanorods using a hydrothermal process in a domestic microwave that ensures ultrafast growth while preserving the high crystal quality of the nanorods. The integration of ZnO as the active layer into a piezo MEMS device requires high crystallinity for better piezoelectric properties and growth on a metallic layer for the bottom electrode functionality. We, therefore, first identify the optimal substrate for ZnO growth and then optimize the seed layer for best crystal orientation as ascertained by HRXRD ω-scan (2.63°) and a super dense morphology to ensure no pinholes or electrode shorting paths. The realization of a membrane MEMS structure incorporating ZnO as the active piezo layer involves another process innovation where we do not pattern the top electrode, as is typical in such piezo MEMS devices, but rather, pattern the bottom electrode using a lift-off process and leave the top electrode as a conformal metallic layer. We describe the entire process of growth and device fabrication in this paper with special attention to the compatibility of the process with MEMS fabrication.

Inferior Turbinate Surgery with a Piezo Device in Rhinoplasty.

Facial Plastic Surgery & Aesthetic MedicineVol. 23, No. 1 Surgical PearlsInferior Turbinate Surgery with a Piezo Device in RhinoplastyBaşak Caypinar Eser and Adem Emre İlhanBaşak Caypinar Eser*Address correspondence to: Başak Caypinar Eser, MD, Special Avcilar Anadolu Hospital, avcılar, Istanbul 34320, Turkey E-mail Address: bskcypnr@hotmail.comSpecial Avcilar Anadolu Hospital, Istanbul, Turkey.Search for more papers by this author and Adem Emre İlhanRinocenter, Istanbul, Turkey.Search for more papers by this authorPublished Online:18 Jan 2021https://doi.org/10.1089/fpsam.2020.0015AboutSectionsView articleView Full TextSupplemental MaterialPDF/EPUBView Supplemental Data Permissions & CitationsPermissionsDownload CitationsTrack CitationsAdd to favorites Back To Publication ShareShare onFacebookTwitterLinked InRedditEmail View articleFiguresReferencesRelatedDetailsCited byThe submucosal approach influences long-term outcomes of refractory obstructive rhinitis: A prospective study and a STROBE analysisAmerican Journal of Otolaryngology, Vol. 44, No. 3Effectiveness of submucosal turbinoplasty in refractory obstructive rhinitis: a prospective comparative trial25 January 2022 | European Archives of Oto-Rhino-Laryngology, Vol. 279, No. 9Piezo-assisted Turbinoplasty Versus Partial Turbinectomy in External Septorhinoplasty: A Prospective Comparative Study in 100 Patients13 January 2022 | Aesthetic Plastic Surgery, Vol. 46, No. 3 Volume 23Issue 1Feb 2021 InformationCopyright 2021, American Academy of Facial Plastic and Reconstructive Surgery, Inc.To cite this article:Başak Caypinar Eser and Adem Emre İlhan.Inferior Turbinate Surgery with a Piezo Device in Rhinoplasty.Facial Plastic Surgery & Aesthetic Medicine.Feb 2021.70-72.http://doi.org/10.1089/fpsam.2020.0015Published in Volume: 23 Issue 1: January 18, 2021Online Ahead of Print:May 7, 2020PDF download

Design and Control of a Piezo Drill for Robotic Piezo-Driven Cell Penetration

Cell penetration is an indispensable step in many cell surgery tasks. Conventionally, cell penetration is achieved by passively indenting and eventually puncturing the cell membrane, during which undesired large cell deformation is induced. Piezo drills have been developed to penetrate cells with less deformation. However, existing piezo drills suffer from large lateral vibration or are incompatible with standard clinical setup. Furthermore, it is challenging to accurately determine the time instance of cell membrane puncturing; thus, the time delay to stop piezo pulsing causes cytoplasm stirring and cell damage. This letter reports a new robotic piezo-driven cell penetration technique, in which the piezo drill device induces small lateral vibrations and is fully compatible with standard clinical setup. Techniques based on corner-feature probabilistic data association filter and motion history images were developed to automatically detect cell membrane breakage by piezo drilling. Experiments on hamster oocytes confirmed that the system is capable of achieving a small cell deformation of 5.68 $\pm$ 2.74 $\mu$ m (vs. 54.29 $\pm$ 10.21 $\mu$ m by passive approach) during cell penetration. Automated detection of membrane breakage had a success rate of 95.0%, and the time delay between membrane breakage and piezo-vibration stoppage was 0.51 $\pm$ 0.27 s vs. 2.32 $\pm$ 0.98 s by manual stoppage of piezo pulsing. This reduced time delay together with smaller cell deformation led to higher oocyte post-penetration survival rate (92.5% vs. 77.5% by passive approach, n = 80 cells).

A proposal of a piezo rotary positioning device: design, modeling and experiments

This article proposes a novel piezo rotary positioning device in which the rotation of the end-effector is generated by the friction driving mechanism principle. Two piezoelectric elements are utilized as motion sources. In this article, a complete study for design, finite element analysis, manufacturing, dynamic model, simulations and experiments is presented. The finite element analysis is applied to evaluate the designed device. Based on results of analysis on the finite element model, a prototype of device is manufactured. The driving resolutions of the end-effector of prototype can be achieved approximately 0.45 × 10–3 rad when the driving voltage of 80 V with frequency of 1 Hz is applied. By taking in account of the nonlinear hysteresis of piezo actuators as well as the complexity of friction mechanism between the end-effector and the movable platform, the predicted dynamic model of the end-effector angular displacement is achieved. Simulations and experiments results show that the prediction model is in good agreement with the actual model. This provides a useful solution for designing and controlling of such rotary devices. So, this rotary device can be controlled automatically by a computer and it has a great potential application in practice.

Nuclear Transfer and Cloning.

Nuclear transfer (NT) and cloning offers a unique and powerful experimental tool to study the mechanisms of gene reprogramming, to establish embryonic stem cells from somatic cells, and to clone live offspring. The process of NT involves two different cells. The first are oocytes, which are enucleated and provide the cellular components required for gene reprogramming and early embryo development. The second are donor cells, and their nuclei are injected into the enucleated oocytes. The donor cell nuclei are reprogrammed in the oocyte cytoplasm. The reconstructed oocytes are then activated and will begin to cleave. The embryos now have a genome identical to the original donor cells. These embryos can be used for basic research or implanting into foster mothers to develop to term. The protocols for mouse NT were developed in 1998 with assistance of the piezo drill device, and in 2000 without assistance of the piezo drill device. In this chapter, a comprehensive update on the techniques and protocols employed to generate mice by NT cloning are summarized based on the latest publications.

Primer embarazo en América Latina utilizando la técnica Piezo-ICSI: reporte de caso

La inyección intracitoplasmática del espermatozoide al ovulo (ICSI) es una técnica de fertilización in vitro en la que un espermatozoide es inyectado al ovocito utilizando una micropipeta biselada, para conseguir la fecundación. Esta técnica, ampliamente usada en reproducción asistida, genera una deformación moderada de la membrana del ovocito, llegando a ser, en algunos casos, nocivo para este. Utilizando la técnica Piezo-ICSI, esta deformación se minimiza, ya que el dispositivo Piezo genera vibración submicrónica en la micropipeta de ICSI, y atraviesa la zona pelúcida sin generar resistencia alguna. No existe evidencia que esta técnica haya logrado un embarazo en América Latina, por lo tanto, se presenta el siguiente reporte como el primer caso de embarazo clínico con actividad cardiaca de 16 semanas de gestación proveniente de un embrión fecundado con la técnica de Piezo-ICSI.

Evaluation of a Piezo-Actuated Sensor for Monitoring Elastic Variations of Its Support with Impedance-Based Measurements.

This study exposes the assessment of a piezo-actuated sensor for monitoring elastic variations (change in Young’s modulus) of a host structure in which it is attached. The host structure is monitored through a coupling interface connected to the piezo-actuated device. Two coupling interfaces were considered (an aluminum cone and a human tooth) for the experimental tests. Three different materials (aluminum, bronze and steel) were prepared to emulate the elastic changes in the support, keeping the geometry as a fixed parameter. The piezo device was characterized from velocity frequency response functions in pursuance to understand how vibration modes stimulate the electrical resistance through electrical resonance peaks of the sensor. An impedance-based analysis (1–20 kHz) was performed to correlate elastic variations with indexes based on root mean square deviation (RMSD) for two observation windows (9.3 to 9.7 kHz and 11.1 to 11.5 kHz). Results show that imposed elastic variations were detected and quantified with the electrical resistance measurements. Moreover, it was demonstrated that the sensitivity of the device was influenced by the type of coupling interface since the cone was more sensitive than the tooth in both observation windows. As a final consideration, results suggest that bio-structures (fruits and bone, among others) could be studied since these can modify naturally its elastic properties.

Respirometer by a piezo device and its application to triage

In this paper, we present a novel respirometer using the effect of piezo devices and show its application to triage. We found that blowing on the piezo device generated several 100 mV voltage and also synchronizes with the respiration. Our detailed investigations of the phenomena showed that it was caused by the pyroelectric effect. In general, the piezo device when used as a sensing device generates output voltage in a batteryless manner and also functions as a buzzer, which can lead to a compact, simple and low-power respirometer. Here, the piezo device was used as a base of respirometer and not only as a respirometer, but also as an alarm sound generator. Thus, the proposed respirometer was realized only by one piezo device and a low-powered microprocessor driven by a small battery. We applied the respirometer to triage and realized a triage sensing system. In the system, we employed the triage priority determination procedure defined as an international standard. The triage sensing system set in a mask detects respiration and displays its condition by turning an LED on and off, synchronizing the respiration and also generating the alarm sound when the respiration falls into the pre-specified ill conditions.