Search results

1 – 10 of over 2000
Open Access
Article
Publication date: 20 June 2022

Radek Doubrava, Martin Oberthor, Petr Bělský and Bohuslav Cabrnoch

The purpose of this paper is to describe the approach for the design of cowlings for a new fast helicopter from the perspective of airworthiness requirements regarding high-speed

Abstract

Purpose

The purpose of this paper is to describe the approach for the design of cowlings for a new fast helicopter from the perspective of airworthiness requirements regarding high-speed impact resistance.

Design/methodology/approach

Validated numerical simulation was applied to flat and simple curved test panels. High-speed camera measurement and non-destructive testing (NDT) results were used for verification of the numerical models. The final design was optimized and verified by validated numerical simulation.

Findings

The comparison between numerical simulation based on static material properties with experimental results of high-speed load shows no significant influence of strain rate effect in composite material.

Research limitations/implications

Owing to the sensitivity of the composite material on technology production, the results are limited by the material used and the production technology.

Practical implications

The application of flat and simple curved test panels for the verification and calibration of numerical models allows the optimized final design of the cowling and reduces the risk of structural non-compliance during verification tests.

Originality/value

Numerical models were verified for simulation of the real composite structure based on high-speed camera results and NDT inspection after impact. The proposed numerical model was simplified for application in a complex design and reduced calculation time.

Details

International Journal of Structural Integrity, vol. 13 no. 4
Type: Research Article
ISSN: 1757-9864

Keywords

Content available
Article
Publication date: 1 September 2005

215

Abstract

Details

Assembly Automation, vol. 25 no. 3
Type: Research Article
ISSN: 0144-5154

Keywords

Content available
Article
Publication date: 1 September 2004

74

Abstract

Details

Sensor Review, vol. 24 no. 3
Type: Research Article
ISSN: 0260-2288

Keywords

Open Access
Article
Publication date: 13 November 2018

Han Wu, Tao Wang, Tuo Dai, Xiaoyu Wang, Yuanzhen Lin and Yizhou Wang

This paper aims to design a vision-based non-contact real-time accurate heart rate (HR) measurement framework for home nursing assistant.

Abstract

Purpose

This paper aims to design a vision-based non-contact real-time accurate heart rate (HR) measurement framework for home nursing assistant.

Design/methodology/approach

The study applied Second-Order Blind Signal Identification (SOBI) algorithm to extract remote HR signal and analyzed it with Fast Fourier Transform (FFT). Multiple regions of interest are chosen and analyzed to obtain a more accurate result.

Findings

An accurate non-contact hear rate (HR) measurement framework is proposed and proved to be efficient.

Originality/value

The contributions of this HR measurement framework are as follows: accurate measurement of HR, real-time performance, robust under various scenes such as conversation, lightweight computation which is suitable and necessary for home nursing assistance. This framework is designed to be flexibly used in various real-life scenes such as domestic health assistance and affectively intelligent agents and is proved to be robust under such scenes.

Details

International Journal of Crowd Science, vol. 2 no. 3
Type: Research Article
ISSN: 2398-7294

Keywords

Content available
Article
Publication date: 16 October 2009

136

Abstract

Details

Aircraft Engineering and Aerospace Technology, vol. 81 no. 6
Type: Research Article
ISSN: 0002-2667

Content available
Article
Publication date: 1 December 2003

308

Abstract

Details

Aircraft Engineering and Aerospace Technology, vol. 75 no. 6
Type: Research Article
ISSN: 0002-2667

Keywords

Content available
Article
Publication date: 1 June 2002

335

Abstract

Details

Assembly Automation, vol. 22 no. 2
Type: Research Article
ISSN: 0144-5154

Keywords

Content available
Article
Publication date: 1 March 2000

135

Abstract

Details

Assembly Automation, vol. 20 no. 1
Type: Research Article
ISSN: 0144-5154

Keywords

Open Access
Article
Publication date: 16 October 2018

Maximilian Schniedenharn, Frederik Wiedemann and Johannes Henrich Schleifenbaum

The purpose of this paper is to introduce an approach in measuring the shielding gas flow within laser powder bed fusion (L-PBF) machines under near-process conditions (regarding…

2900

Abstract

Purpose

The purpose of this paper is to introduce an approach in measuring the shielding gas flow within laser powder bed fusion (L-PBF) machines under near-process conditions (regarding oxygen content and shielding gas flow).

Design/methodology/approach

The measurements are made sequentially using a hot-wire anemometer. After a short introduction into the measurement technique, the system which places the measurement probe within the machine is described. Finally, the measured shielding gas flow of a commercial L-PBF machine is presented.

Findings

An approach to measure the shielding gas flow within SLM machines has been developed and successfully tested. The use of a thermal anemometer along with an automated probe-placement system enables the space-resolved measurement of the flow speed and its turbulence.

Research limitations/implications

The used single-normal (SN) hot-wire anemometer does not provide the flow vectors’ orientation. Using a probe with two or three hot-films and an improved placement system will provide more information about the flow and less disturbance to it.

Originality/value

A measurement system which allows the measurement of the shielding gas flow within commercial L-PBF machines is presented. This enables the correlation of the shielding gas flow with the resulting parts’ quality.

Details

Rapid Prototyping Journal, vol. 24 no. 8
Type: Research Article
ISSN: 1355-2546

Keywords

Open Access
Article
Publication date: 10 January 2024

Yifan Shi, Yuan Wang, Xiaozhou Liu and Ping Wang

Straightness measurement of rail weld joint is of essential importance to railway maintenance. Due to the lack of efficient measurement equipment, there has been limited in-depth…

Abstract

Purpose

Straightness measurement of rail weld joint is of essential importance to railway maintenance. Due to the lack of efficient measurement equipment, there has been limited in-depth research on rail weld joint with a 5-m wavelength range, leaving a significant knowledge gap in this field.

Design/methodology/approach

In this study, the authors used the well-established inertial reference method (IR-method), and the state-of-the-art multi-point chord reference method (MCR-method). Two methods have been applied in different types of rail straightness measurement trollies, respectively. These instruments were tested in a high-speed rail section within a certain region of China. The test results were ultimately validated through using traditional straightedge and feeler gauge methods as reference data to evaluate the rail weld joint straightness within the 5-m wavelength range.

Findings

The research reveals that IR-method and MCR-method produce reasonably similar measurement results for wavelengths below 1 m. However, MCR-method outperforms IR-method in terms of accuracy for wavelengths exceeding 3 m. Furthermore, it was observed that IR-method, while operating at a slower speed, carries the risk of derailing and is incapable of detecting rail weld joints and low joints within the track.

Originality/value

The research compare two methods’ measurement effects in a longer wavelength range and demonstrate the superiority of MCR-method.

1 – 10 of over 2000