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Article
Publication date: 19 March 2020

Wenlei Zhang, Mingxu Ma, Haiyan Li, Jiapeng Yu and Zhenwei Zhang

The purpose of this paper is to discriminate fake interference caused by polygonal approximation so as to achieve accurate assembly sequence planning and assembly simulation.

202

Abstract

Purpose

The purpose of this paper is to discriminate fake interference caused by polygonal approximation so as to achieve accurate assembly sequence planning and assembly simulation.

Design/methodology/approach

An approximation zone model is proposed to formulate polygonal approximation. Fake interference is discriminated from hard interference by evaluating if polygonal models intersect within corresponding approximation zones. To reduce the computation, the surface-surface, surface-end face and end face-end face intersection test methods have been developed to evaluate the intersection and obtain collision data. An updated collision detection algorithm with this method is presented, which is implemented by a system named AutoAssem.

Findings

This method has been applied to a set of products such as a valve for assembly interference matrix generation, static and dynamic collision detection. The results show that it ensures the accuracy of assembly sequence planning and assembly simulation for polygonal models.

Practical implications

This method facilitates assembly design in the virtual environment with polygonal models. It can also be applied to computer aided design systems to achieve quick and accurate collision detection.

Originality/value

Fake interference between polygonal models may result in serious errors in assembly sequence planning and assembly simulation. Assembly zone model and novel polygon intersection verification methods have been proposed to effectively tackle this problem. Compared to current methods, this method considers valid penetration direction and approximation difference, does not need to process complicated auxiliary data and can be easily integrated with current collision detection methods.

Details

Assembly Automation, vol. 40 no. 4
Type: Research Article
ISSN: 0144-5154

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Article
Publication date: 1 March 2023

Yuzhen Zhao, Mingxu Zhao, Huimin Zhang, Xiangrong Zhao, Yang Zhao, Zhun Guo, Jianjing Gao, Cheng Ma and Yongming Zhang

This paper aims to prepare third-order nonlinear optical (NLO) organic materials with large nonlinear optimization value, high damage threshold and ultrafast response time.

67

Abstract

Purpose

This paper aims to prepare third-order nonlinear optical (NLO) organic materials with large nonlinear optimization value, high damage threshold and ultrafast response time.

Design/methodology/approach

A series of novel symmetric and asymmetric compounds possessing third-order NLO properties were synthesized using 1,3,5-tribromobenzene as the basis. The photophysical and electrochemical properties, as well as the click reactions, were characterized by means of UV–VIS–NIR absorption spectroscopy and cyclic voltammetry.

Findings

The donor–acceptor chromophores were inserted into compound, making the molecule to have a broader absorption in the near-infrared regions and a narrower optical and electrochemical band gap. It also formed an electron-delocalized organic system, which has larger effects on achieving a third-order NLO response. The third-order NLO phenomenon of benzene ring complexes was experimentally studied at 532 nm using Z-scan technology, and some compounds showed the expected NLO properties.

Originality/value

The click products exhibit more NLO phenomena by performing different click combinations to the side groups, opening new perspectives on using the system in a variety of photoelectric applications.

Details

Pigment & Resin Technology, vol. 53 no. 3
Type: Research Article
ISSN: 0369-9420

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Article
Publication date: 19 February 2019

Xiaonan Chen, Jun Huang, Mingxu Yi and Yalin Pan

The purpose of this paper is to develop a flexible design-oriented development cost method for commercial aviation aircraft based on small sample and poor information.

370

Abstract

Purpose

The purpose of this paper is to develop a flexible design-oriented development cost method for commercial aviation aircraft based on small sample and poor information.

Design/methodology/approach

To predict the development cost of commercial aviation aircraft accurately, the methodology is based on the collected cost data and actual technical, and then the cost prediction relationships derived from an exhaustive statistical and filtered from regression analysis are incorporated. A series of regression equations with high regression coefficient are yielded after the cost driving factors of the development cost are fixed. Next, several sets of equations with high regression coefficient are selected for final integration. It is a flexible method that can be used efficiently to predict the cost of commercial aviation aircraft.

Findings

The development of commercial aviation aircraft has relatively a late start and no cost prediction model has been suitable for small sample, the proposed method is expected and is rather desirable.

Practical implications

By comparing the approach with the ordinary regression model and back propagation (BP) neural network, the scheme in this work is more efficient and convenient.

Originality/value

The results obtained in this paper show that the proposed method not only has a certain degree of versatility, but also can provide a preliminary prediction of the development cost of commercial aviation aircraft.

Details

Aircraft Engineering and Aerospace Technology, vol. 91 no. 4
Type: Research Article
ISSN: 1748-8842

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Article
Publication date: 11 June 2020

Shaoze Lu, Jun Huang and Mingxu Yi

By reducing the coating thickness of the weak scattering source, the coating weight of the absorbing material can be reduced by 35% with little effect on the RCS.

284

Abstract

Purpose

By reducing the coating thickness of the weak scattering source, the coating weight of the absorbing material can be reduced by 35% with little effect on the RCS.

Design/methodology/approach

To alleviate the weight-increasing problem caused by a large number of coating of absorbing materials, a method for zonal coating of absorbing materials for a stealth helicopter was proposed. By appropriately reducing the thickness of the coating at the secondary scattering locations, the amount of coating used is significantly reduced.

Findings

Compared with the full-coated, the zonal coating scheme achieves the corresponding RCS reduction effect.

Practical implications

Zonal coating design can achieve the effect of reducing coating weight and cost.

Originality/value

The effects of different coating methods on RCS were verified by electromagnetic scattering simulation, and the applicability of the zonal coating design of the absorbing material to the stealth helicopter was verified.

Details

Aircraft Engineering and Aerospace Technology, vol. 92 no. 7
Type: Research Article
ISSN: 1748-8842

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Article
Publication date: 14 March 2023

Xiaonan Chen, Shiyong Chu, Guanglin Zhang, Xuanyou Chen, Jun Huang and Mingxu Yi

General aviation aircraft has a wide range of applications, and effective cost management is one of the hot spots in the research of general aviation manufacturers. The purpose of…

298

Abstract

Purpose

General aviation aircraft has a wide range of applications, and effective cost management is one of the hot spots in the research of general aviation manufacturers. The purpose of this paper is to build a flexible engineering method to predict maintenance cost of general aviation aircraft.

Design/methodology/approach

To establish a reasonable general aviation aircraft maintenance cost prediction model, it is necessary to analyze the influencing factors and extract the main components of maintenance cost. The maintenance cost is divided by engineering method, and the estimation model of each component cost is established. Then, the general aviation aircraft maintenance cost model is obtained. The results show that the relative error of this method is between 13% and 20%, which has a good estimation accuracy and can be effectively used to estimate the maintenance cost of general aviation aircraft.

Findings

The maintenance cost plays an important role in the life cycle cost of general aviation aircraft. Accurate cost prediction method is of great significance to the optimal design of general aviation aircraft. However, there are few prediction models suitable for maintenance cost, the proposed approach is meaningful and quite desirable.

Originality/value

To some extent, this method overcomes the shortage of the work on maintenance cost prediction for general aviation aircraft. The model established in this paper has certain generality, which can provide some reference for general aviation aircraft design and operation enterprises.

Details

Aircraft Engineering and Aerospace Technology, vol. 95 no. 6
Type: Research Article
ISSN: 1748-8842

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Article
Publication date: 20 September 2023

Ke Gao, Xiaoqin Zhou, Rongqi Wang, Mingxu Fan and Haochen Han

Compared with the high stiffness of traditional CNC machine tools, the structural stiffness of industrial robots is usually less than 1 N/µm. Chatter not only affects the quality…

229

Abstract

Purpose

Compared with the high stiffness of traditional CNC machine tools, the structural stiffness of industrial robots is usually less than 1 N/µm. Chatter not only affects the quality of robotic milling but also reduces the accuracy of the milling process. The purpose of this paper is to reduce chatter in the robotic machining process.

Design/methodology/approach

First, the mode coupling chatter mechanism is analyzed. Then the milling force model and the principal stiffness model are established. Finally, the robot milling stability optimization method is proposed. The method considered functional redundancies, and a new robot milling stability index is proposed to improve the quality of milling operations.

Findings

The experimental results prove a significant reduction in force fluctuations and surface roughness after using the proposed robotic milling stability optimization method.

Originality/value

In this paper, a new robot milling stability index and a new robot milling stability optimization method are proposed. This method can significantly increase the milling stability and improve the milling quality, which can be widely used in the industry.

Details

Industrial Robot: the international journal of robotics research and application, vol. 50 no. 6
Type: Research Article
ISSN: 0143-991X

Keywords

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Article
Publication date: 23 July 2019

Yacong Wu, Jun Huang, Mingxu Yi and Chaopu Zhang

The purpose of this paper is to introduce the theoretical basis of N-order spectral spreading-compressing (SSC) frequency shift interference algorithm and expand it to active…

127

Abstract

Purpose

The purpose of this paper is to introduce the theoretical basis of N-order spectral spreading-compressing (SSC) frequency shift interference algorithm and expand it to active cancellation. An active cancellation simulation and verification system based on N-order SSC algorithm is established and carried out; simultaneously, the absorbing material coating stealth simulation of two kinds of thickness is carried out to compare the stealth effect with active cancellation system.

Design/methodology/approach

The active cancellation method based on N-order SSC algorithm is proposed based on theoretical formula derivation; the active cancellation simulation and verification system is established in MATLAB/Simulink. The full-size model is built by CATIA and meshed by hypermesh. The omnidirectional radar cross section (RCS) is calculated in cadFEKO, and the results are analyzed in postFEKO.

Findings

The simulations are implemented on a stealth fighter, and results show that after active cancellation, the peak of spectrum analyzer has reduced in all azimuths, the omnidirectional RCS has also decreased and the detection probability of almost all azimuths has dropped under 50 per cent. The absorbing material coating stealth simulations of two kinds of thickness are carried out, and results show that the stealth effect of active cancellation is much better than absorbing material coating.

Practical implications

An active cancellation system based on SSC algorithm is proposed in this paper, and the effect of active cancellation is verified and compared with that of absorbing materials. A new method for the current active stealth is provided in this paper.

Originality/value

Active cancellation simulation and verification system is established. RCS calculation module, signal-to-noise-ratio (SNR) calculation module and detection probability module are built to verify the effect of active cancellation system. Simultaneously, the absorbing material coating stealth simulation is carried out, and the stealth effect of absorbing material coating and active cancellation are compared and analyzed.

Details

Aircraft Engineering and Aerospace Technology, vol. 91 no. 7
Type: Research Article
ISSN: 1748-8842

Keywords

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Article
Publication date: 20 October 2020

Sapna Pandit and R.C. Mittal

This paper aims to propose a novel approach based on uniform scale-3 Haar wavelets for unsteady state space fractional advection-dispersion partial differential equation which…

203

Abstract

Purpose

This paper aims to propose a novel approach based on uniform scale-3 Haar wavelets for unsteady state space fractional advection-dispersion partial differential equation which arises in complex network, fluid dynamics in porous media, biology, chemistry and biochemistry, electrode – electrolyte polarization, finance, system control, etc.

Design/methodology/approach

Scale-3 Haar wavelets are used to approximate the space and time variables. Scale-3 Haar wavelets converts the problems into linear system. After that Gauss elimination is used to find the wavelet coefficients.

Findings

A novel algorithm based on Haar wavelet for two-dimensional fractional partial differential equations is established. Error estimation has been derived by use of property of compactly supported orthonormality. The correctness and effectiveness of the theoretical arguments by numerical tests are confirmed.

Originality/value

Scale-3 Haar wavelets are used first time for these types of problems. Second, error analysis in new work in this direction.

Details

Engineering Computations, vol. 38 no. 4
Type: Research Article
ISSN: 0264-4401

Keywords

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