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Article
Publication date: 13 June 2019

Rui 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…

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115

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.

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Article
Publication date: 1 December 1986

Next generation commercial and civil aircraft will require a de‐centralised system of obtaining and employing air data. Rosemount has capitalised on its massive experience…

Abstract

Next generation commercial and civil aircraft will require a de‐centralised system of obtaining and employing air data. Rosemount has capitalised on its massive experience in sensor technology and electronics to meet the future needs of the manufacturer and the operator with a product concept called the Distributed Air Data System (DADS).

Details

Aircraft Engineering and Aerospace Technology, vol. 58 no. 12
Type: Research Article
ISSN: 0002-2667

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Article
Publication date: 1 March 1982

S. Monchaud and R. Prat

A simple ultrasonic sensor coupled with a colour sensing system has been designed and built in the laboratory of the French National Institute of Applied Science at…

Abstract

A simple ultrasonic sensor coupled with a colour sensing system has been designed and built in the laboratory of the French National Institute of Applied Science at Rennes, and mounted on the laboratory's VESA mobile robot. It can distinguish simple configurations of obstacles and measure their distance from the robot, and within certain limits of illumination can classify obstacles to eight reference colours.

Details

Sensor Review, vol. 2 no. 3
Type: Research Article
ISSN: 0260-2288

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Article
Publication date: 1 September 1970

Accles & Pollock Ltd. of Oldbury, Worcestershire, a TI Steel Tube Division company, will be exhibiting a comprehensive range of precision steel tube and tubular products…

Abstract

Accles & Pollock Ltd. of Oldbury, Worcestershire, a TI Steel Tube Division company, will be exhibiting a comprehensive range of precision steel tube and tubular products, including plain, annularly convoluted and thin wall tube, at Farnborough.

Details

Aircraft Engineering and Aerospace Technology, vol. 42 no. 9
Type: Research Article
ISSN: 0002-2667

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Article
Publication date: 1 April 1989

T.C. Chung and H.A. Moore

Tape automated bonding (TAB) is one technology which is becoming widely adopted for interconnecting integrated circuits to a substrate or package. Both destructive and…

Abstract

Tape automated bonding (TAB) is one technology which is becoming widely adopted for interconnecting integrated circuits to a substrate or package. Both destructive and non‐destructive test methods for evaluation of TAB bonds are analysed and criticised. The key parameters and general guidelines of a destructive beampull test set‐up are identified and presented. The key features of four different non‐destructive test methods are described and discussed. It is found that no universal solution exists for non‐destructive evaluation of TAB bonds although some methods may be more useful than others under certain conditions and constraints. Data and experimental procedure are presented for correlation of scanning laser acoustic microscopy and beampull data.

Details

Circuit World, vol. 16 no. 1
Type: Research Article
ISSN: 0305-6120

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Article
Publication date: 1 October 2000

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193

Abstract

Details

Aircraft Engineering and Aerospace Technology, vol. 72 no. 5
Type: Research Article
ISSN: 0002-2667

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Article
Publication date: 1 August 2005

Lars Skyttner

To propose a new military academic area called the “Science of Military Command and Control” which will demand an entirely new way of thinking regarding decision‐making…

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1969

Abstract

Purpose

To propose a new military academic area called the “Science of Military Command and Control” which will demand an entirely new way of thinking regarding decision‐making command and control and use of modern technology.

Design/methodology/approach

Defines basic terms and concepts of the discipline and a meta‐theory consisting of General Systems Theory and its related areas is presented.

Findings

Three main perspectives are recommended where the first is General Systems Theory, the second is the Cybernetics Regulatory Paradigm and the third is Communication and Information Theory. The components of military command and control system were analysed and a general model for information system development recommended.

Research limitations/implications

Current thinking in favour of a “network‐defense” that is based on information and communication technology has changed the traditional perspective. New thinking and research development is required. New research using scientific approach is needed.

Practical implications

Shows that the old and exact strategies for Swedish defence has totally changed. New military academic area is proposed and a general model outlined.

Originality/value

Proposes a new way of thinking which will affect future military planning. A cybernetic/systemic methodology provides solutions.

Details

Kybernetes, vol. 34 no. 7/8
Type: Research Article
ISSN: 0368-492X

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Article
Publication date: 16 October 2009

Anne Tolman and Tommi Parkkila

The purpose of this paper is to describe how healthy performance of facilities can be monitored and performance data delivered as information flow according to specific…

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1102

Abstract

Purpose

The purpose of this paper is to describe how healthy performance of facilities can be monitored and performance data delivered as information flow according to specific user groups' needs.

Design/methodology/approach

The context of performance in facilities is described, and a tool for the collection of performance data and communicating the data as relevant information for the facility management (FM) and other stake holders is developed.

Findings

Various user groups are utilizing the same performance data to ensure optimal and healthy conditions. The integration of performance data to deliver meaningful and exploitable results for each user requires collection of the relevant data, compilation of data into information, and delivery of user specific information to the correct instance. A performance sensing system with data management was developed into a FM tool for this purpose.

Practical implications

FM is enabled to real time decision making by sensor‐based performance monitoring.

Originality/value

The results are generic and FM tools may be built on this basis for the specific information and display needs of various FM professionals and other stakeholders.

Details

Facilities, vol. 27 no. 11/12
Type: Research Article
ISSN: 0263-2772

Keywords

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Article
Publication date: 6 July 2015

Elzbieta Lesniewska

The purpose of this paper is to discuss the operation of new generation electromagnetic current-to-voltage transducer. The aim of research was analysis of behaviour of…

Abstract

Purpose

The purpose of this paper is to discuss the operation of new generation electromagnetic current-to-voltage transducer. The aim of research was analysis of behaviour of considered current-to-voltage transducers during operation. The main problem was to estimate whether the external fields are able to change the value of the secondary voltage and that the replacement of the casing material by a conductive or ferromagnetic material will increase the immunity of the transducer to external magnetic fields. The immunity of current-to-voltage transducers to the external fields is very important because it influences the proper functioning of the protection system.

Design/methodology/approach

The use of analytical methods to assess the influence of external fields was impossible due to the complexity of the geometry. The 3D computations were necessary because of different cross sections of circuit boards at different heights. Therefore the numerical 3D field-and-circuit method based on finite element method was applied. The wide range of dimensions in computation system, ranging from 0.15 mm (print paths) to 0.22 m, made it necessary to use the mesh of millions of elements. The division of this type of system into elements requires a diverse and extremely dense mesh in the area of printed circuits board (PCBs).

Findings

The 3D analysis of magnetic field distribution was performed for different external field effect upon a current-to-voltage transducer. The magnetic field distributions and the induced secondary voltage for several different cases were presented. As a conclusion it can be said that in this particular case the magnetic shield is most effective. The influence of external magnetic fields caused by currents passing through the other neighbouring phase bars near are insignificant for the transducer with non-magnetic core.

Practical implications

Commonly used in measuring and protection systems of the transmission lines are induction instrument transformers. The instrument transformers are very precise devices and their errors are counted in tenths of a per cent, and phase displacement of signals in minutes. Especially in HV systems they are very big and their cores are heavy. Replacement of instrument transformers by the current to voltage transducers cooperating with electronic measuring systems will reduce the size and cost of devices.

Originality/value

The requirements set for protective current transformers concern the transformation of currents, with high accuracy, especially at transient states. Therefore magnetic characteristics of their cores should be linear. It causes that cores are large and have some air gaps. Current-to-voltage transducers based on Rogowski coil are particularly suitable for the replacement of the protective current transformers because of their linearity. The traditional technologies used for making Rogowski coil consisted in winding a wire on a non-magnetic carcass. The development of technology has enabled the use of new technologies PCB high density interconnect in the production of Rogowski coil.

Details

COMPEL: The International Journal for Computation and Mathematics in Electrical and Electronic Engineering, vol. 34 no. 4
Type: Research Article
ISSN: 0332-1649

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Article
Publication date: 18 January 2016

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…

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

Sensor Review, vol. 36 no. 1
Type: Research Article
ISSN: 0260-2288

Keywords

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