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1 – 8 of 8Rui Zhang, Lei Zhao, Dan Xie, Jinlong Song, Wendong Zhang, Lihu Pan and Yanhua Zhang
This study aims to simulate and test the performance of a transmitting and receiving capacitive micro-machined ultrasonic transducer (CMUT). Aimed at detecting demand of the CMUT…
Abstract
Purpose
This study aims to simulate and test the performance of a transmitting and receiving capacitive micro-machined ultrasonic transducer (CMUT). Aimed at detecting demand of the CMUT, a matched integrated adjustment circuit was designed through analyzing processing methods of transducer’s weak echo signal.
Design/methodology/approach
Based on the analysis of CMUT array structure and work principle, the CMUT units are designed and the dynamic performance analysis of SIMULINK is given according to the demand of underwater detecting. A transceiver isolation circuit is used to make transmission mode and receiving mode separate. A detection circuit is designed based on the transimpedance amplifier to achieve extraction of high-frequency and weak signal.
Findings
Through experimentation, the effectiveness of the CMUT performance simulation and the transceiver integrated adjustment circuit were verified. In addition, the test showed that CMUT with 400 kHz frequency has wider bandwidth and better dynamic characteristics than other similar transducers.
Originality/value
This paper provides a theoretical basis and design reference for the development and application of CMUT technology.
Details
Keywords
- MEMS
- Dynamic performance
- Ultrasonic sensors
- Underwater applications
- Detection circuit
- Transmission transducer
- Capacitive micro-machined ultrasonic transducer
- Receipt and transmission transducer
- MEMS
- Dynamic performance
- Ultrasonic sensors
- Underwater applications
- Detection circuit
- Transmission transducer
- Capacitive micro-machined ultrasonic transducer
Hongliang Wang, Xiangjun Wang, Changde He and Chenyang Xue
As a new type of ultrasonic transducer with significant advantages, capacitive micromachined ultrasonic transducer (CMUT) has good application prospect. The reception…
Abstract
Purpose
As a new type of ultrasonic transducer with significant advantages, capacitive micromachined ultrasonic transducer (CMUT) has good application prospect. The reception characteristic of the CMUT is one of the important factors determining the application effect. This paper aims to study the reception characteristics of CMUT.
Design/methodology/approach
In this paper, the state equation is deduced and the analysis model is established in SIMULINK environment based on the lumped parameter system model of the CMUT cell. Based on this analysis model, the influencing factors of CMUT reception characteristics are studied and investigated, and the time-domain and frequency-domain characteristics are investigated in detail.
Findings
The analysis results show that parameters directly affect the reception characteristics of the CMUT, such as direct current (DC) bias voltage, input sound pressure amplitude and frequency. At the same time, the measurement system is built and the reception characteristics are verified.
Originality/value
This paper provides an effective method for rapid analyzing the reception characteristics of CMUT. These results provide an important theoretical basis and reference for further optimization of CMUT structure design, and lay a good foundation for the practical application measurement.
Details
Keywords
Rui Zhang, Wendong Zhang, Changde He, Jinlong Song, Linfeng Mu, Juan Cui, Yongmei Zhang and Chenyang Xue
The purpose of this paper was to develop a novel capacitive micromachined ultrasonic transducer (CMUT) reception and transmission linear array for underwater imaging at 400 kHz…
Abstract
Purpose
The purpose of this paper was to develop a novel capacitive micromachined ultrasonic transducer (CMUT) reception and transmission linear array for underwater imaging at 400 kHz. Compared with traditional CMUTs, the developed transducer array offers higher electromechanical coupling coefficient and higher directivity performance.
Design/methodology/approach
The configuration of the newly developed CMUT reception and transmission array was determined by the authors’ previous research into new element structures with patterned top electrodes and into directivity simulation analysis. Using the Si-Silicon on insulator (Si-SOI) bonding technique and the principle of acoustic impedance matching, the CMUT array was fabricated and packaged. In addition, underwater imaging system design and testing based on the packaged CMUT 1 × 16 array were completed.
Findings
The simulation results showed that the optimized CMUT array configuration was selected. Furthermore, the designed configuration of the CMUT 1 × 16 linear array was good enough to guarantee high angular resolution. The underwater experiments were conducted to demonstrate that this CMUT array can be of great benefit in imaging applications.
Practical implications
Based on our research, the CMUT linear array has good directivity and good impedance matching with water and can be used for obstacle avoidance, distance measurement and imaging underwater.
Originality/value
This research provides a basis for CMUT directivity theory and array design. CMUT array presented in this paper has good directivity and has been applied in the underwater imaging, resulting in a huge market potential in underwater detection systems.
Details
Keywords
Tian Zhang, Wendong Zhang, XingLing Shao and Yang Wu
Because of the small size and high integration of capacitive micromachined ultrasonic transducer (CMUT) component, it can be made into large-scale array, but this lead to high…
Abstract
Purpose
Because of the small size and high integration of capacitive micromachined ultrasonic transducer (CMUT) component, it can be made into large-scale array, but this lead to high hardware complexity, so the purpose of this paper is to use less elements to achieve better imaging results. In this research, an optimized sparse array is studied, which can suppress the side lobe and reduce the imaging artifacts compared with the equispaced sparse array with the same number of elements.
Design/methodology/approach
Genetic algorithm is used to sparse the CMUT linear array, and Kaiser window apodization is added to reduce imaging artifacts, the beam pattern and peak-to-side lobe ratio are calculated, point targets imaging comparisons are performed. Furthermore, a 256-elements CMUT linear array is used to carry out the imaging experiment of embedded mass and forearm blood vessel, and the imaging results are compared quantitatively.
Findings
Through the imaging comparison of embedded mass and forearm blood vessel, the feasibility of optimized sparse array of CMUT is verified, and the purpose of reducing the hardware complexity is achieved.
Originality/value
This research provides a basis for the large-scale CMUT array to reduce the hardware complexity and the amount of calculation. At present, the CMUT array has been used in medical ultrasound imaging and has huge market potential.
Details
Keywords
Junhui Zhang, Sai Zhang, Yuhua Yang and Wendong Zhang
Based on the micro-electro-mechanical system (MEMS) technology, acoustic emission sensors have gained popularity owing to their small size, consistency, affordability and easy…
Abstract
Purpose
Based on the micro-electro-mechanical system (MEMS) technology, acoustic emission sensors have gained popularity owing to their small size, consistency, affordability and easy integration. This study aims to provide direction for the advancement of MEMS acoustic emission sensors and predict their future potential for structural health detection of microprecision instruments.
Design/methodology/approach
This paper summarizes the recent research progress of three MEMS acoustic emission sensors, compares their individual strengths and weaknesses, analyzes their research focus and predicts their development trend in the future.
Findings
Piezoresistive, piezoelectric and capacitive MEMS acoustic emission sensors are the three main streams of MEMS acoustic emission sensors, which have their own advantages and disadvantages. The existing research has not been applied in practice, and MEMS acoustic emission sensor still needs further research in the aspects of wide frequency/high sensitivity, good robustness and integration with complementary metal oxide semiconductor. MEMS acoustic emission sensor has great development potential.
Originality/value
In this paper, the existing research achievements of MEMS acoustic emission sensors are described systematically, and the further development direction of MEMS acoustic emission sensors in the future research field is pointed out. It provides an important reference value for the actual weak acoustic emission signal detection in narrow structures.
Details
Keywords
Shuai Na, Guo-an Tang and Li-fen Chen
Orbital maneuver of the spacecraft can cause large-amplitude vibration of its flexible solar array, which leads to large dynamic stress and a risk of structural failure and…
Abstract
Purpose
Orbital maneuver of the spacecraft can cause large-amplitude vibration of its flexible solar array, which leads to large dynamic stress and a risk of structural failure and fatigue failure. This paper aims to provide a method to reduce such vibration.
Design/methodology/approach
Through controlling the rotation at the root of the solar array, a method of vibration reduction is proposed using zero-placement input shaping technique. Experimental research on a beam scale model of the solar array is performed to verify the effectiveness of the method. Simulation of a detailed example is carried out to investigate whether the method can be applied in engineering.
Findings
The experimental results demonstrate the effectiveness of such method. The simulation results indicate that, by adopting the presented method, the vibration induced by orbital maneuver can be diminished remarkably.
Research limitations/implications
Studies on the robustness of the method are left for further work. Additionally, since only the first-order bending vibration of the flexible solar array is eliminated, further improvements are required such that the stated method can be applied to suppress multi-mode vibration.
Practical implications
An effective method is proposed for spacecraft designers planning to actively suppress the vibration of flexible solar array during the process of orbital maneuver.
Originality/value
This paper fulfils a source of theoretical and experimental studies for orbital maneuver system design and offers practical help for spacecraft designers.
Details
Keywords
Mansoor Ahmad, Ayhan Bozkurt and Omid Farhanieh
This paper aims to Separation and sorting of biological cells is desirable in many applications for analyzing cell properties, such as disease diagnostics, drugs delivery…
Abstract
Purpose
This paper aims to Separation and sorting of biological cells is desirable in many applications for analyzing cell properties, such as disease diagnostics, drugs delivery, chemical processing and therapeutics.
Design/methodology/approach
Acoustic energy-based bioparticle separation is a simple, viable, bio-compatible and contact-less technique using, which can separate the bioparticles based on their density and size, with-out labeling the sample particles.
Findings
Conventionally available bioparticle separation techniques as fluorescence and immunomagnetic may cause a serious threat to the life of the cells due to various compatibility issues. Moreover, they also require an extra pre-processing labeling step. Contrarily, label-free separation can be considered as an alternative solution to the traditional bio-particle separation methods, due to their simpler operating principles and lower cost constraints. Acoustic based particle separation methods have captured a lot of attention among the other reported label-free particle separation techniques because of the numerous advantages it offers.
Practical implications
This study tries to briefly cover the developments of different acoustic-based particle separation techniques over the years. Unlike the conventional surveys on general bioparticles separation, this study is focused particularly on the acoustic-based particle separation. The study would provide a comprehensive guide for the future researchers especially working in the field of the acoustics, in studying and designing the acoustic-based particle separation techniques.
Originality/value
The study insights a brief theory of different types of acoustic waves and their interaction with the bioparticles is considered, followed by acoustic-based particle separation devices reported till the date. The integration of acoustic-based separation techniques with other methods and with each other is also discussed. Finally, all major aspects like the approach, and productivity, etc., of the adopted acoustic particle separation methods are sketched in this article.
Details