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Article
Publication date: 4 September 2017

Qing Wang, Yadong Dou, Jiangxiong Li, Yinglin Ke, Patrick Keogh and Paul G. Maropoulos

The purpose of this paper is to present an optimal posture evaluation model to control the assembly gaps in aircraft wing assembly. The gaps between two mating surfaces…

Abstract

Purpose

The purpose of this paper is to present an optimal posture evaluation model to control the assembly gaps in aircraft wing assembly. The gaps between two mating surfaces should be strictly controlled in precision manufacturing. Oversizing of gaps will decrease the dimensional accuracy and may reduce the fatigue life of a mechanical product. To reduce the gaps and keep them within tolerance, the relative posture (orientation and position) of two components should be optimized in the assembly process.

Design/methodology/approach

Based on the step alignment strategy, i.e. preliminary alignment and refined alignment, the concept of a small posture transformation (SPT) is introduced. In the preliminary alignment, an initial posture is estimated by a set of auxiliary locating points, with which the components can be quickly aligned near each other. In the refined alignment, the assembly gaps are calculated and the formulation of the gaps with component posture is derived by the SPT. A comprehensive weighted minimization model with gap tolerance constraints is established for redistributing the gaps in multi-regions. Powell-Hestenes-Rockafellar optimization, Singular Value Decomposition and K-Dimensional tree searching are introduced for the solution of the optimal posture for localization.

Findings

Using the SPT, the trigonometric posture transformation is linearized, which benefits the iterative solution process. Through the constrained model, overall gaps are minimized and excess gaps are controlled within tolerance.

Practical implications

This method has been tested with simulated model data and real product data, the results of which have shown efficient coordination of mating components.

Originality/value

This paper proposed an optimal posture evaluation method for minimizing the gaps between mating surfaces through component adjustments. This will promote the assembly automation and variation control in aircraft wing assembly.

Details

Assembly Automation, vol. 37 no. 4
Type: Research Article
ISSN: 0144-5154

Keywords

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Article
Publication date: 8 January 2018

Oussama Ammar and Philippe Chereau

This paper aims to identify the differentiated paths followed by firms to innovate in business models, among four different strategic postures and also to determine the…

Abstract

Purpose

This paper aims to identify the differentiated paths followed by firms to innovate in business models, among four different strategic postures and also to determine the innovation interactions between business model components, among strategic postures. The authors intend to highlight the differentiated patterns of business model innovation (BMI) in each strategic posture and provide guidance to small and medium enterprises (SMEs) managers regarding the suitable alignments of business model components when they innovate in their business model.

Design/methodology/approach

The research model developed and tested in this work uses a composite model that borrows from the logic of Miles and Snow’s cycle of adaptive strategic choices as well as Demil and Lecocq’s perspective of permanent change within and between components of a business model. The authors’ model is designed first to encompass the differentiated patterns characterizing the relationships between the strategic posture of defender, prospector and analyzer profiles and the related innovation attributes of their business model components. The study was conducted with independent French manufacturing SMEs ranging from 10 to 250 employees in size and having revenues below €50m (European Commission, 2007). The analysed sample includes 169 firms from 14 sectors representative of French manufacturing SMEs.

Findings

Results confirm the differentiated propensity to adopt specific BMI behaviours among strategic postures. The authors also highlight the differentiated interactions between and within BMI components. These results suggest that SMEs tend to leverage specific BMI components related to their entrepreneurial, engineering and administrative choices. Thus, firms tend to evolve in a posture-specific, path-dependent dynamic consistency in which BMI attributes interact towards a limited set of alternatives, thus anchoring the new business model into strategic choices. It has been shown that the predictability of strategy–BMI alignment is contingent on the level of fit between empirically derived strategic profile attributes and Miles and Snow’s ideal profile attributes.

Research limitations/implications

This paper investigates strategy–BMI alignments without addressing such alignments from the standpoint of firm performance. Still, performance from a BMI perspective lies in the ability of the firm to sustain the dynamic consistency of its business model components by identifying the effects of change in interactions between and within components on overall BM performance. Further studies should explore dynamic consistency as a means for firms to generate and maintain performance by innovating in their business model when facing specific contingencies. The conceptual framework designed for the present research seems appropriate for conducting such an investigation on the performance implications of strategy–BMI fit.

Practical implications

This research offers insights regarding manufacturing SMEs seeking guidance when changing business strategy. Indeed, by combining Miles and Snow’s configurational framework of strategic postures with Demil and Lecocq’s RCOV BM framework, the authors provide insights that can bridge the gap between intended strategy and realized strategy. The authors suggest that when realizing new strategic choices, SMEs should favour behaviours of BMI that are likely to fit the new intended strategic posture. Accordingly, the authors introduce a set of field-based BMI alignments specific to firms’ strategic posture to support the strategic management of innovation in SMEs.

Originality/value

By unravelling the alignments between strategic posture and business model innovation, this work contributes to enlightening the dynamics of Miles and Snow’s adaptive cycle. Indeed, viewing Miles and Snow’s typology from the configurational perspective of BMI provides a clearer picture of the adaptive cycle through which BMI reflects the path-dependent process of the formation of the firm’s strategic posture through the transformation of its business model.

Details

European Business Review, vol. 30 no. 1
Type: Research Article
ISSN: 0955-534X

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Article
Publication date: 2 February 2015

Hou Yukan, Li Yuan, Zhang Jie, Wen-Bin Tang and Jiang Shoushan

The purpose of this study is to present a new and relatively inexpensive method for posture evaluation of the positioning of the wing-body assembly. Positioning is an…

Abstract

Purpose

The purpose of this study is to present a new and relatively inexpensive method for posture evaluation of the positioning of the wing-body assembly. Positioning is an essential process to guarantee alignment accuracy in an assembly line.

Design/methodology/approach

The studied method includes a structural set-up and a software algorithm used to process a set of experimental input data to compute the actual position of the wing with respect to the ideal position, which is proposed considering measurement uncertainty, the deviation caused by large errors in measurement points and the different tolerance requirements.

Findings

The studied method has been found to be simple and effective in addition to being highly accurate. Compared with most of the current methods that have been developed with optical equipment, it is more cost- and space-efficient. The automation process determines how much operation time will be saved.

Practical implications

The studied method has been applied in an actual assembly line, and the economic and time savings illustrate its benefits.

Originality/value

This method provides an attractive wing-body assembly solution for those enterprises that want to find a low-cost option or have limited measuring space for optical equipment. It can also be the basis for the accurate assembly of other large parts for aircraft and other vessels.

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Article
Publication date: 21 August 2017

Wei Jiang, Gongping Wu, Fei Fan, Wei Wang, Jie Zhang, Xuhui Ye and Peng Zhou

This paper aims to develop a robot for tightening charged bolt to solve the shortcomings of high labor intensity, low efficiency, high risk and poor reliability in…

Abstract

Purpose

This paper aims to develop a robot for tightening charged bolt to solve the shortcomings of high labor intensity, low efficiency, high risk and poor reliability in artificially tightening drainage board bolt of strain clamp for high voltage transmission line. Realizing bolt-nut capture and location by manipulator is a critical process to complete the whole working task. To solve such key technology, an autonomous location control method for N-joint robot manipulator based on kinematics was proposed.

Design/methodology/approach

Through D-H kinematics analysis under flexible working environment of transmission line, the autonomous location control of double manipulators can be abstracted as a nonlinear approximation problem based on joint inverse kinematics. In addition, regarding the complex coupling relationship among different joint angles and the complex decoupling process which leads to the non-uniqueness of inverse solution, an improved backpropagation (BP) network was proposed based on the combination of dynamic adaptive adjustment of learning rate and variable momentum factor, so that the inverse kinematics of manipulator can be solved and the optimization evaluation mechanism of inverse solution can be presented. The proposed autonomous location control method is of adaptability to flexible environment and structural parameters of different drainage boards. The simulation results verified the effectiveness of the proposed method. Compared with the other location control, this method can achieve faster location speed, higher precision and lower hardware cost. Finally, the field operation test further validated that such autonomous location control method was of strong engineering practicability.

Findings

The proposed autonomous location control method is adaptable to a flexible environment and to the structural parameters of different types of drainage board. Simulation results confirm the effectiveness of the proposed method, which, in comparison with other approaches to location control, can achieve faster location, higher precision and lower hardware cost. Finally, a field test further confirms the engineering practicability of the proposed autonomous location control method.

Originality/value

The proposed method can achieve faster location speed, higher precision which meet the requirement of real-time control relative to the standard BP algorithm. Moreover, it is of strong adaptability to flexible environment and structural parameters for different drainage board. Field operation experiment further validated the engineering practicability of the method.

Details

Industrial Robot: An International Journal, vol. 44 no. 5
Type: Research Article
ISSN: 0143-991X

Keywords

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Article
Publication date: 19 August 2019

Zhihao Wang, Wenliang Chen, Min Wang, Qinghe Xu and Can Huang

The purpose of this study is to improve the position and posture accuracy of posture alignment mechanism. The automatic drilling and riveting machine is an important…

Abstract

Purpose

The purpose of this study is to improve the position and posture accuracy of posture alignment mechanism. The automatic drilling and riveting machine is an important equipment for aircraft assembly. The alignment accuracy of position and posture of the bracket type posture alignment mechanism has a great influence on the operation effect of the machine. Therefore, it is necessary to carry out the kinematic calibration.

Design/methodology/approach

Based on analysis of elastic deformation of the bracket and geometric errors of the posture alignment mechanism, an improved method of kinematic calibration was proposed. The position and posture errors of bracket caused by geometric errors were separated from those caused by gravity. The method of reduction of dimensions was applied to deal with the error coefficient matrix in error identification, and it did not change the coefficient of the error terms. The target position and its posture were corrected to improve the error compensation accuracy. Furthermore, numerical simulation and experimental verification were carried out.

Findings

The simulation and experimental results show that considering the influence of the elastic deformation of the bracket on the calibration effect, the error identification accuracy and compensation accuracy can be improved. The maximum value of position error is reduced from 5.33 mm to 1.60 × 10−1 mm and the maximum value of posture error is reduced from 1.07 × 10−3 rad to 6.02 × 10−4 rad, which is superior to the accuracy without considering the gravity factor.

Originality/value

This paper presents a calibration method considering the effects of geometric errors and gravity. By separating position and posture errors caused by different factors and correcting the target position and its posture, the results of the calibration method are greatly improved. The proposed method might be applied to any parallel mechanism based on the positioner.

Details

Industrial Robot: the international journal of robotics research and application, vol. 46 no. 5
Type: Research Article
ISSN: 0143-991X

Keywords

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Book part
Publication date: 3 October 2006

Javier Gimeno, Ming-Jer Chen and Jonghoon Bae

We investigate the dynamics of competitive repositioning of firms in the deregulated U.S. airline industry (1979–1995) in terms of a firm's target market, strategic posture

Abstract

We investigate the dynamics of competitive repositioning of firms in the deregulated U.S. airline industry (1979–1995) in terms of a firm's target market, strategic posture, and resource endowment relative to other firms in the industry. We suggest that, despite strong inertia in competitive positions, the direction of repositioning responds to external and internal alignment considerations. For external alignment, we examined how firms changed their competitive positioning to mimic the positions of similar, successful firms, and to differentiate themselves when experiencing intense rivalry. For internal alignment, we examined how firms changed their position in each dimension to align with the other dimensions of positioning. This internal alignment led to convergent positioning moves for firms with similar resource endowments and strategic postures, and divergent moves for firms with similar target markets and strategic postures. The evidence suggests that repositioning moves in terms of target markets and resource endowments are more sensitive to external and internal alignment considerations, but that changes in strategic posture are subject to very high inertia and do not appear to respond well to alignment considerations.

Details

Ecology and Strategy
Type: Book
ISBN: 978-1-84950-435-5

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Article
Publication date: 3 September 2018

Shuanggao Li, Zhengping Deng, Qi Zeng and Xiang Huang

The assembly of large component in out-field is an important part for the usage and maintenance of aircrafts, which is mostly manually accomplished at present, as the…

Abstract

Purpose

The assembly of large component in out-field is an important part for the usage and maintenance of aircrafts, which is mostly manually accomplished at present, as the commonly used large-volume measurement systems are usually inapplicable. This paper aims to propose a novel coaxial alignment method for large aircraft component assembly using distributed monocular vision.

Design/methodology/approach

For each of the mating holes on the components, a monocular vision module is applied to measure the poses of holes, which together shape a distributed monocular vision system. A new unconstrained hole pose optimization model is developed considering the complicated wearing on hole edges, and it is solved by a iterative reweighted particle swarm optimization (IR-PSO) method. Based on the obtained poses of holes, a Plücker line coordinates-based method is proposed for the relative posture evaluation between the components, and the analytical solution of posture parameters is derived. The required movements for coaxial alignment are finally calculated using the kinematics model of parallel mechanism.

Findings

The IR-PSO method derived more accurate hole pose arguments than the state-of-the-art method under complicated wearing situation of holes, and is much more efficient due to the elimination of constraints. The accuracy of the Plücker line coordinates-based relative posture evaluation (PRPE) method is competitive with the singular value decomposition (SVD) method, but it does not rely on the corresponding of point set; thus, it is more appropriate for coaxial alignment.

Practical implications

An automatic coaxial alignment system (ACAS) has been developed for the assembly of a large pilotless aircraft, and a coaxial error of 0.04 mm is realized.

Originality/value

The IR-PSO method can be applied for pose optimization of other cylindrical object, and the analytical solution of Plücker line coordinates-based axes registration is derived for the first time.

Details

Assembly Automation, vol. 38 no. 4
Type: Research Article
ISSN: 0144-5154

Keywords

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Abstract

Details

Leading with Presence: Fundamental Tools and Insights for Impactful, Engaging Leadership
Type: Book
ISBN: 978-1-78714-599-3

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Article
Publication date: 6 February 2017

Qiang Fang, Weidong Chen, Anan Zhao, Changxi Deng and Shaohua Fei

In aircraft wing–fuselage assembly, the distributed multi-point support layout of positioners causes fuselage to deform under gravity load, leading to assembly difficulty…

Abstract

Purpose

In aircraft wing–fuselage assembly, the distributed multi-point support layout of positioners causes fuselage to deform under gravity load, leading to assembly difficulty and assembly stress. This paper aims to propose a hybrid force position control method to balance aerodynamic shape accuracy and deformation of assembly area, thereby correcting assembly deformation and reducing assembly stress.

Design/methodology/approach

Force and position control axes of positioners are selected based on screw theory and ellipsoid method. The position-control axes follow the posture trajectory to align the fuselage posture. To exert force on the fuselage and correct the deformations, the force-control axes follow the contact force derived by using orthogonal experiments and partial least squares regression (PLSR). Finite element simulation and one-dimension deformation correction experiment are conducted to verify the validity of this method.

Findings

Simulation results indicate that hybrid force position control method can correct assembly deformation and improve the wing–fuselage assembly quality significantly. Experiment on specimen verifies the effect of this method indirectly.

Originality/value

The proposed method gives a solution to solve the deformation problem during aircraft wing-fuselage assembly, thereby reducing assembly stress and improving assembly quality.

Details

Assembly Automation, vol. 37 no. 1
Type: Research Article
ISSN: 0144-5154

Keywords

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Article
Publication date: 11 October 2019

Yifan Zhang, Qing Wang, Anan Zhao and Yinglin Ke

This paper aims to improve the alignment accuracy of large components in aircraft assembly and an evaluation algorithm, which is based on manufacture accuracy and…

Abstract

Purpose

This paper aims to improve the alignment accuracy of large components in aircraft assembly and an evaluation algorithm, which is based on manufacture accuracy and coordination accuracy, is proposed.

Design/methodology/approach

With relative deviations of manufacturing feature points and coordinate feature points, an evaluation function of assembly error is constructed. Then the optimization model of large aircraft digital alignment is established to minimize the synthesis assembly error with tolerance requirements, which consist of three-dimensional (3D) tolerance of manufacturing feature points and relative tolerance between coordination feature points. The non-linear constrained optimization problem is solved by Lagrange multiplier method and quasi-Newton method with its initial value provided by the singular value decomposition method.

Findings

The optimized postures of large components are obtained, which makes the tolerance of both manufacturing and coordination requirements be met. Concurrently, the synthesis assembly error is minimized. Compared to the result of the singular value decomposition method, the algorithm is validated in three typical cases with practical data.

Practical implications

The proposed method has been used in several aircraft assembly projects and gained a good effect.

Originality/value

This paper proposes a method to optimize the manufacturing and coordination accuracy with tolerance constraints when the postures of several components are adjusted at the same time. The results of this paper will help to improve the quality of component assemblies.

Details

Assembly Automation, vol. 40 no. 2
Type: Research Article
ISSN: 0144-5154

Keywords

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