scholarly journals Process Emulation System for High-Power Piezoelectric Ultrasonic Actuators

2015 ◽  
Vol 2 (3-4) ◽  
pp. 201-205
Author(s):  
Igor Ille ◽  
Sebastian Mojrzisch ◽  
Jens Twiefel

Abstract Ultrasonic actuators are used for a wide field of applications. The vibration energy can be used to realize many processes like ultrasonic welding or bonding. Furthermore there are many processes which run more efficient and faster combined with ultrasonic vibration like ultrasonic-assisted turning or drilling. Piezoelectric transducers are the main part of those applications. Most of the applications have a time-variant load behavior and need an amplitude feedback control to guarantee a stable process. To ensure correct function tests of the feedback control systems have to be done. In this case the processes have to be executed in association with a high number of cycles. To emulate the behavior of the environment the automotive and aerospace industries use hardware in the loop systems since a long time but there is no such a method for ultrasonic systems. This paper presents a method to realize high dynamic load emulation for different ultrasonic applications. Using a piezoelectric transformer it is possible to reproduce load curves by active damping on the secondary side of the transformer using a current proportional digital feedback circuit. A theoretical and experimental study of hardware in the loop system for ultrasonic applications is given by this paper. The present system allows testing a wide field of feedback control algorithms with high flexibility and a high number of cycles by utilization of low-cost components. This proceeding decreases design periods in association with feedback control.

Energies ◽  
2020 ◽  
Vol 13 (16) ◽  
pp. 4119
Author(s):  
Chaoyu Chen ◽  
Lei Zhang ◽  
Wenbo Ding ◽  
Lijun Chen ◽  
Jinkang Liu ◽  
...  

In recent years, rapid advancements have developed in multifunctional and wearable electronics, which call for more lightweight, flexible energy sources. However, traditional disposable batteries and rechargeable batteries are not very suitable because of their bulky appearance, limited capacity, low flexibility, and environmental pollution problem. Here, by applying a mature manufacturing technology that has existed in the textile field for a long time, a woven fabric triboelectric nanogenerator (WF-TENG) with a thinner structure that can be mass-fabricated with low cost, perfect stability, and high flexibility is designed and reported. Due to the good intrinsic quality of TENGs, the maximum voltage of this WF-TENG can easily reach 250 V under a pressure of 3.5 kPa and a tapping frequency of 0.33 Hz. Because of the stable plain-woven structure, the output voltage can remain relatively stable even after the WF-TENG has been working for about 5 h continuously, clearly demonstrating its robustness and practical value. Moreover, good sensitivity endows this WF-TENG with the capability of being applied as self-powered sensors, such as a self-powered smart real-time gait-recognizing sock. This WF-TENG shows us a simple and effective method to fabricate a wearable textile product with functional ability, which is very meaningful for future research.


2019 ◽  
Vol 10 (1) ◽  
pp. 73-89 ◽  
Author(s):  
Noriaki Sakamoto

Purpose This paper aims to examine a congestion situation of a certain type of restaurant in a theme park (Tokyo Disney Resort) by a simulation based on Little’s law, which is a basic principle in Queueing theory. In the restaurant, a guest (customer) lines up to order, pay and receive dishes. A problem is that even when a guest can easily find vacant tables, it takes a long time to receive dishes. Because guests can see there are vacant tables, there are many tweets of complaints. This situation is a factor to undermine customer satisfaction. Design/methodology/approach This paper proposes dedicated special menu lines only providing special set as one solution that can be realized at a low cost to reduce vacant tables. Here, if the number of special menu lines is fixed, the difference between a queue in regular lines and that in special menu lines will be big. To shorten the difference, the author proposes a technique to regulate by using feedback control (Proportional control or Fuzzy control). Findings The simulation result shows that the number of vacant tables decreases by about 16 per cent compared with the current situation. Originality/value This paper considers a specific restaurant, but the proposed method can be applied to the same type of restaurant in the theme park. If the restaurant in the theme park is crowded, the feedback control of the queue brings new possibilities.


Author(s):  
Yasunobu Iwai ◽  
Koichi Shinozaki ◽  
Daiki Tanaka

Abstract Compared with space parts, consumer parts are highly functional, low cost, compact and lightweight. Therefore, their increased usage in space applications is expected. Prior testing and evaluation on space applicability are necessary because consumer parts do not have quality guarantees for space application [1]. However, in the conventional reliability evaluation method, the test takes a long time, and the problem is that the robustness of the target sample can’t be evaluated in a short time. In this report, we apply to the latest TSOP PEM (Thin Small Outline Package Plastic Encapsulated Microcircuit) an evaluation method that combines preconditioning and HALT (Highly Accelerated Limit Test), which is a test method that causes failures in a short time under very severe environmental conditions. We show that this method can evaluate the robustness of TSOP PEMs including solder connections in a short time. In addition, the validity of this evaluation method for TSOP PEM is shown by comparing with the evaluation results of thermal shock test and life test, which are conventional reliability evaluation methods.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Md Atiqur Rahman ◽  
Mohammad Tariqul Islam ◽  
Mandeep Singh Jit Singh ◽  
Md Samsuzzaman ◽  
Muhammad E. H. Chowdhury

AbstractIn this article, we propose SNG (single negative) metamaterial fabricated on Mg–Zn ferrite-based flexible microwave composites. Firstly, the flexible composites are synthesized by the sol-gel method having four different molecular compositions of MgxZn(1−x)Fe2O4, which are denoted as Mg20, Mg40, Mg60, and Mg80. The structural, morphological, and microwave properties of the synthesized flexible composites are analyzed using X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), and conventional dielectric assessment kit (DAK) to justify their possible application as dielectric substrate at microwave frequency regime. Thus the average grain size is found from 20 to 24 nm, and the dielectric constants are 6.01, 5.10, 4.19, and 3.28, as well as loss tangents, are 0.002, 0.004, 0.006, and 0.008 for the prepared Mg–Zn ferrites, i.e., Mg20, Mg40, Mg60, and Mg80 respectively. Besides, the prepared low-cost Mg–Zn ferrite composites exhibit high flexibility and lightweight, which makes them a potential candidate as a metamaterial substrate. Furthermore, a single negative (SNG) metamaterial unit cell is fabricated on the prepared, flexible microwave composites, and their essential electromagnetic behaviors are observed. Very good effective medium ratios (EMR) vales are obtained from 14.65 to 18.47, which ensure the compactness of the fabricated prototypes with a physical dimension of 8 × 6.5 mm2. Also, the proposed materials have shown better performances comparing with conventional FR4 and RO4533 materials, and they have covered S-, C-, X-, Ku-, and K-band of microwave frequency region. Thus, the prepared, flexible SNG metamaterials on MgxZn(1−x)Fe2O4 composites are suitable for microwave and flexible technologies.


Molecules ◽  
2021 ◽  
Vol 26 (12) ◽  
pp. 3694
Author(s):  
Luminita Georgeta Confederat ◽  
Cristina Gabriela Tuchilus ◽  
Maria Dragan ◽  
Mousa Sha’at ◽  
Oana Maria Dragostin

Despite the advantages presented by synthetic polymers such as strength and durability, the lack of biodegradability associated with the persistence in the environment for a long time turned the attention of researchers to natural polymers. Being biodegradable, biopolymers proved to be extremely beneficial to the environment. At present, they represent an important class of materials with applications in all economic sectors, but also in medicine. They find applications as absorbers, cosmetics, controlled drug delivery, tissue engineering, etc. Chitosan is one of the natural polymers which raised a strong interest for researchers due to some exceptional properties such as biodegradability, biocompatibility, nontoxicity, non-antigenicity, low-cost and numerous pharmacological properties as antimicrobial, antitumor, antioxidant, antidiabetic, immunoenhancing. In addition to this, the free amino and hydroxyl groups make it susceptible to a series of structural modulations, obtaining some derivatives with different biomedical applications. This review approaches the physico-chemical and pharmacological properties of chitosan and its derivatives, focusing on the antimicrobial potential including mechanism of action, factors that influence the antimicrobial activity and the activity against resistant strains, topics of great interest in the context of the concern raised by the available therapeutic options for infections, especially with resistant strains.


2021 ◽  
Author(s):  
Mingming Su ◽  
Yajing Hu ◽  
Ao Yu ◽  
Zhiyao Peng ◽  
Wangtao Long ◽  
...  

Broadband photodetectors fabricated with organic molecules have the advantages of low cost, high flexibility, easy processing and low-temperature requirement. Fullerene molecules, due to the electron acceptor and photoinduced electron transfer...


Sensors ◽  
2020 ◽  
Vol 20 (19) ◽  
pp. 5697
Author(s):  
Chang Sun ◽  
Shihong Yue ◽  
Qi Li ◽  
Huaxiang Wang

Component fraction (CF) is one of the most important parameters in multiple-phase flow. Due to the complexity of the solid–liquid two-phase flow, the CF estimation remains unsolved both in scientific research and industrial application for a long time. Electrical resistance tomography (ERT) is an advanced type of conductivity detection technique due to its low-cost, fast-response, non-invasive, and non-radiation characteristics. However, when the existing ERT method is used to measure the CF value in solid–liquid two-phase flow in dredging engineering, there are at least three problems: (1) the dependence of reference distribution whose CF value is zero; (2) the size of the detected objects may be too small to be found by ERT; and (3) there is no efficient way to estimate the effect of artifacts in ERT. In this paper, we proposed a method based on the clustering technique, where a fast-fuzzy clustering algorithm is used to partition the ERT image to three clusters that respond to liquid, solid phases, and their mixtures and artifacts, respectively. The clustering algorithm does not need any reference distribution in the CF estimation. In the case of small solid objects or artifacts, the CF value remains effectively computed by prior information. To validate the new method, a group of typical CF estimations in dredging engineering were implemented. Results show that the new method can effectively overcome the limitations of the existing method, and can provide a practical and more accurate way for CF estimation.


2014 ◽  
Vol 08 (02) ◽  
pp. 209-227 ◽  
Author(s):  
Håkon Kvale Stensland ◽  
Vamsidhar Reddy Gaddam ◽  
Marius Tennøe ◽  
Espen Helgedagsrud ◽  
Mikkel Næss ◽  
...  

There are many scenarios where high resolution, wide field of view video is useful. Such panorama video may be generated using camera arrays where the feeds from multiple cameras pointing at different parts of the captured area are stitched together. However, processing the different steps of a panorama video pipeline in real-time is challenging due to the high data rates and the stringent timeliness requirements. In our research, we use panorama video in a sport analysis system called Bagadus. This system is deployed at Alfheim stadium in Tromsø, and due to live usage, the video events must be generated in real-time. In this paper, we describe our real-time panorama system built using a low-cost CCD HD video camera array. We describe how we have implemented different components and evaluated alternatives. The performance results from experiments ran on commodity hardware with and without co-processors like graphics processing units (GPUs) show that the entire pipeline is able to run in real-time.


Meccanica ◽  
2021 ◽  
Vol 56 (5) ◽  
pp. 1223-1237
Author(s):  
Giacomo Moretti ◽  
Andrea Scialò ◽  
Giovanni Malara ◽  
Giovanni Gerardo Muscolo ◽  
Felice Arena ◽  
...  

AbstractDielectric elastomer generators (DEGs) are soft electrostatic generators based on low-cost electroactive polymer materials. These devices have attracted the attention of the marine energy community as a promising solution to implement economically viable wave energy converters (WECs). This paper introduces a hardware-in-the-loop (HIL) simulation framework for a class of WECs that combines the concept of the oscillating water columns (OWCs) with the DEGs. The proposed HIL system replicates in a laboratory environment the realistic operating conditions of an OWC/DEG plant, while drastically reducing the experimental burden compared to wave tank or sea tests. The HIL simulator is driven by a closed-loop real-time hydrodynamic model that is based on a novel coupling criterion which allows rendering a realistic dynamic response for a diversity of scenarios, including large scale DEG plants, whose dimensions and topologies are largely different from those available in the HIL setup. A case study is also introduced, which simulates the application of DEGs on an OWC plant installed in a mild real sea laboratory test-site. Comparisons with available real sea-test data demonstrated the ability of the HIL setup to effectively replicate a realistic operating scenario. The insights gathered on the promising performance of the analysed OWC/DEG systems pave the way to pursue further sea trials in the future.


The railway system is one of the most widely used modes of transportation due to its low cost. To keep the railway system running smoothly, continuous track monitoring is needed. These days, the railway system is manually supervised. As a result, there is a greater risk of disasters, such as fatalities, occurring as a result of human error while monitoring. The main problem with manual system monitoring is that it takes a long time to process all of the necessary data. Since railway tracks are built over thousands of miles, it is virtually impossible to manually control the device over such a longdistance. At railway crossings, a lot of accidents happen. Crossing gates are usually opened and closed after receiving direct input from the station. If there is a delay in obtaining information from the station, there is a risk of swearing incidents. The main goal of this research is to simplify and protect the railway system. The proposed system employs Force Sensitive Resistor (FSR) detectors for automatic side road crossing protection. Any type of breakage, as well as vibration, can be efficiently detected with a higher degree of precision using Light Dependent Resistor (LRR) and laser detectors. In the event of an unexpected situation, such as an accident, the GSM module will begin communicating via message with the nearest control room for assistance. Sonar sensors are often used for obstacle avoidance when something unexpectedly appears in front of the train. The Internet of Things (IoT) has been added to the system to allow it to be monitored from anywhere in the sphere. The Arduino UNO is a microcontroller that serves as the system's backbone. The framework has the potential to be extremely beneficial to our country's railway economic growth.


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