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Article
Publication date: 15 August 2016

Qilong Yuan, I-Ming Chen and Teguh Santoso Lembono

Taping, covering objects with masking tapes, is a common process before conducting surface treatments such as plasma spraying and painting. Manual taping is tedious and takes a…

280

Abstract

Purpose

Taping, covering objects with masking tapes, is a common process before conducting surface treatments such as plasma spraying and painting. Manual taping is tedious and takes a lot of effort of the workers. This paper aims to introduce an automatic agile robotic system and corresponding algorithm to do the surface taping.

Design/methodology/approach

The taping process is a special process which requires correct tape orientation and proper allocation of the masking tape for the coverage. This paper discusses on the design of the novel automatic system consisting of a robot manipulator, a rotating platform, a 3D scanner and a specially designed novel taping end-effectors. Meanwhile, the taping path planning to cover the region of interests is introduced.

Findings

Currently, cylindrical and freeform surfaces have been tested. With improvements on new sets of taping tools and more detailed taping method, taping of general surfaces can be conducted using such system in future.

Originality/value

The introduced taping path planning method is a novel method first talking about the mathematical model of the taping process. Such taping solution with the taping tool and the taping methodology can be combined as a very useful and practical taping package to replace the work of human in such tedious and time-consuming works.

Details

Industrial Robot: An International Journal, vol. 43 no. 5
Type: Research Article
ISSN: 0143-991X

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Article
Publication date: 17 November 2021

Zhoupeng Han, Chenkai Tian, Zihan Zhou and Qilong Yuan

Complex mechanical 3D computer-aided design (CAD) model embodies rich implicit design knowledge. Through discovering the key function parts and key function module in 3D CAD…

232

Abstract

Purpose

Complex mechanical 3D computer-aided design (CAD) model embodies rich implicit design knowledge. Through discovering the key function parts and key function module in 3D CAD assembly model in advance, it can promote the designers’ understanding and reuse efficiency of 3D assembly model in design reuse.

Design/methodology/approach

An approach for discovering key function module in complex mechanical 3D CAD assembly model is proposed. First, assembly network for 3D CAD assembly model is constructed, where the topology structure characteristics of 3D assembly model are analyzed based on complex network centrality. The degree centrality, closeness centrality, betweenness centrality and mutual information of node are used to evaluate the importance of the parts in 3D assembly model. Then, a multi-attribute decision model for part-node importance is established, and the comprehensive evaluation for key function parts in 3D assembly model is accomplished by combining Analytic Hierarchy Process and Technique for Order Preference by Similarity to an Ideal Solution (TOPSIS). Subsequently, a community discovery of function module in assembly model-based Clauset–Newman–Moore (CNM)-Centrality is given in details. Finally, 3D CAD assembly model of worm gear reducer is taken as an example to verify the effectiveness and feasibility of proposed method.

Findings

The key function part in CAD assembly model is evaluated comprehensively considering assembly topology more objectively. In addition, the key function module containing key function part is discovered from CAD assembly model by using CNM-Centrality-based community discovery.

Practical implications

The approach can be used for discovering important design knowledge from complex CAD assembly model when reusing the assembly model. It can help designers capture and understand the design thinking and intent, improve the reuse efficiency and quality.

Originality/value

The paper first proposes an approach for discovering key function module in complex mechanical 3D CAD assembly model taking advantage of complex network theory, where the key function part is evaluated using node centrality and TOPSIS, and the key function module is identified based on community discovery.

Details

Assembly Automation, vol. 42 no. 1
Type: Research Article
ISSN: 0144-5154

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Article
Publication date: 5 May 2023

Zhijian Wang, Yin Wang, Lin Liu, Wengsheng Zhu, Jing Li, Yujie Zhao, Haijun Pang and Qilong Wu

The aim of this study is to first investigate the surface integrity of cylindrical rollers under grinding process and then design a reasonable superfinishing process that improve…

98

Abstract

Purpose

The aim of this study is to first investigate the surface integrity of cylindrical rollers under grinding process and then design a reasonable superfinishing process that improve the anti-fatigue performance of cylindrical rollers by optimization of the surface integrity.

Design/methodology/approach

First, the white and dark layers produced by the grinding process is analyzed by microscope. Then, the influence of oilstone pressure on the stock removal, surface precision and crowned profile are explored. Finally, an optimal superfinishing process and a novel turnaround device are designed to improve surface integrity.

Findings

The experimental results show that as the oilstone pressure increases, the stock removal first increases and then remains stable. This hints that the stock removal of a single-time superfinishing process has an upper limit. In the current conditions, the maximum stock removal is 6 µm. Double-time superfinishing process and the turnover device can effectively eliminate the white and dark layers and improve the symmetric of roller profile. In addition, the surface precision is also improved.

Originality/value

The surface integrity of bearing rollers is very important to the application of industry field. The findings and the methods in the study can be helpful to improve the surface integrity of the bearing rollers.

Details

Industrial Lubrication and Tribology, vol. 75 no. 5
Type: Research Article
ISSN: 0036-8792

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Article
Publication date: 16 December 2024

Wujiu Pan, Heng Ma, Jian Li, Qilong Wu, Junyi Wang, Jianwen Bao, Lele Sun and Peng Gao

Aero-engine casings commonly use composite cylindrical shell structures with excellent properties such as corrosion resistance and fatigue resistance. Still, their vibration…

19

Abstract

Purpose

Aero-engine casings commonly use composite cylindrical shell structures with excellent properties such as corrosion resistance and fatigue resistance. Still, their vibration behavior is relatively complex and may cause fatigue vibration damage, so it is essential to analyze the vibration characteristics of composite cylindrical shells. The purpose of this paper is to analyze the vibration characteristics of multilayer composite cylindrical shells subjected to external pressures and having different interlayer thickness ratios and provide some theoretical basis for the fatigue damage prediction of cylindrical shell casing to ensure the safety and stability of the engine during flight.

Design/methodology/approach

Firstly, the vibration differential equation with external pressure is established based on Soedel theory considering nonlinear effects, while four symmetric boundary conditions are chosen to constrain the cylindrical shell. Then the Rayleigh–Ritz method, which is more efficient and accurate in calculating large structural systems, is applied to solve the problem, and the theoretical model of three-layer cylindrical shell under external pressure is established. The accuracy of the model is verified by comparing the data with the specialized literature. Subsequently, the effects of different external pressures and different thickness-to-diameter ratios, different length-to-diameter ratios and different interlayer thickness percentages on the natural frequency of multilayer composite cylindrical shells were investigated by control variable analysis.

Findings

The conclusions obtained show that the external pressure increases the natural frequency of the cylindrical shell and that the frequency characteristics of the cylindrical shell vary for different boundary conditions. The effect of length-to-diameter ratio, thickness-to-diameter ratio and the percentage of the thickness of the intermediate layer on the natural frequency of the cylindrical shell are significantly increased under external pressure. Because the presence of external pressure increases the frequency of the cylindrical shell by about 70%, it has almost no effect on the frequency at the minimum number of circumferential waves, and the effect on the frequency at the maximum number of circumferential waves is reduced to about 50%. The frequencies in the SL-SL boundary condition are all in perfect agreement with the S-S boundary condition under the influence of different influencing factors.

Originality/value

In this paper, the effect of external pressure and the natural properties of the cylindrical shell under external pressure on the cylindrical shell’s frequency is considered, emphasizing the effect of different layer thickness ratios on the frequency. This paper aims to summarize the changing law between the natural frequency of the cylindrical shell itself and different design parameters during the flight pressure process. Reliable theoretical predictions are provided for analyzing the vibrational behavior of shells subjected to external pressures in aerospace, as well as a database for the practical production of cylindrical shells.

Details

Engineering Computations, vol. 42 no. 1
Type: Research Article
ISSN: 0264-4401

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Article
Publication date: 2 August 2024

Qilong Wu and Qidan Zhu

To improve the robustness of carrier-based unmanned aerial vehicle (UAV) with actuator faults attitude tracking control system, this paper aims to propose a fixed-time…

86

Abstract

Purpose

To improve the robustness of carrier-based unmanned aerial vehicle (UAV) with actuator faults attitude tracking control system, this paper aims to propose a fixed-time backstepping (FXTBSC) fault-tolerant control based on a fixed-time extended state observer.

Design/methodology/approach

A fixed-time extended state observer (FXTESO) is designed to estimate the total disturbance including nonlinear, coupling, actuator faults and external disturbances. The integration of backstepping control and fixed-time technology ensures fixed-time convergence.

Findings

The simulation results of tracking the desired attitude angle show that the anti-interference, fault tolerance and tracking accuracy of FXTBSC-FXTESO are better than the BSC-ESO control method.

Originality/value

Different from the traditional BSC-ESO, the convergence speed and convergence accuracy of FXTBSC-FXTESO proposed in this paper are better than conventional extended state observer. And the fixed time controller has the advantages of high tracking accuracy, fault tolerance and anti-interference ability.

Details

Aircraft Engineering and Aerospace Technology, vol. 96 no. 6
Type: Research Article
ISSN: 1748-8842

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Article
Publication date: 29 October 2019

Sadia Berzou, Djamil Krouf, Nawal Taleb-Dida and Akila Guenzet

The purpose of this study is to evaluate the effects of flaxseed (L. usitatissimum [Linn]) on blood pressure, redox status markers and acetylcholinesterase enzyme activity in…

126

Abstract

Purpose

The purpose of this study is to evaluate the effects of flaxseed (L. usitatissimum [Linn]) on blood pressure, redox status markers and acetylcholinesterase enzyme activity in ouabain-induced hypertension in normal Wistar rats.

Design/methodology/approach

Male Wistar rats weighing 250 ± 7 g (n = 24) fed with an experimental diet containing 20 per cent casein were divided into three groups (n = 8) and received a daily subcutaneous injection of either 0.9 per cent saline solution (T group) or 10 µg/kg/day of ouabain diluted in saline solution-treated Oub-Lu or not with 1 per cent of flaxseed (L. usitatissimum) mixed in the diet for 21 days.

Findings

The results showed that treatment with flaxseed had a significant effect (p < 0.05) in decreasing systolic, diastolic blood pressure, mean arterial pressure and the heart rate in hypertensive rats. Total and non-HDL cholesterol levels were reduced by –26 and –35 per cent; p = 0.04, respectively. Concentrations of thiobarbituric acid-reactive substances were significantly decreased by –85 and –42 per cent (p = 0.001 and p = 0.04), respectively in the plasma and heart. Nitric oxide levels were increased in the aorta (+ 63 per cent; p = 0.001). Moreover, in the heart and aorta, a significant increase was noted in the thiol contents (+81 and +69 per cent; p = 0.001, respectively), glutathione peroxidase (+50 per cent; p = 0.03 and p = 0.01, respectively) and acetylcholinesterase activities (75 and +19 per cent, respectively; p = 0.001 and p = 0.04).

Originality/value

These results suggest hypotensive, cardiomoderating and antioxidant effects of flaxseed in ouabain-induced hypertension in the rat. In addition, it promotes a significant increase of the acetylcholinesterase activity in tissues.

Details

Nutrition & Food Science , vol. 50 no. 4
Type: Research Article
ISSN: 0034-6659

Keywords

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