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Computer‐aided fixture design (CAFD) techniques have been advanced so rapidly that computers can now generate fixture configurations automatically, for both modular fixtures and dedicated fixtures. Computer‐aided fixture design verification (CAFDV) is the techniques for verifying and improving existing fixture designs. It verifies the followings: geometric constraining ability, achieved tolerance, fixturing stability, and fixturing accessibility. Two models – one geometric and one kinematic – are created for the verification.

This paper develops the statistical error analysis model for assembling, to derive measures of controlling the geometric variations in assembly with multiple assembly stations, and to provide a statistical tolerance prediction/distribution toolkit integrated with CAD system for responding quickly to market opportunities with reduced manufacturing costs and improved quality. First the homogeneous transformation is used to describe the location and orientation of assembly features, parts and other related surfaces. The desired location and orientation, and the related fixturing configuration (including locator position and orientation) are automatically extracted from CAD models. The location and orientation errors are represented with differential transformations. The statistical error prediction model is formulated and the related algorithms integrated with the CAD system so that the complex geometric information can be directly accessed. In the prediction model, the manufacturing process (joining) error, induced by heat deformation in welding, is taken into account.

Near-net-shaped processes of jet engine blade have better performance in both reducing the material waste during production and improving work reliability in service, while the geometric features of blade, both sculptured surface and thin-walled shape, make the precise machining of blade challenging and difficult owing to its dynamics behaviors under complex clamping and machining loads. This paper aims to present a fundamental approach on modeling and performance analysis of the blade–fixture system.

A computerized framework on the complex blade–fixture dynamic behavior has been developed. Theoretical mechanic analysis on blade fixturing and machining is proposed with an especial emphasis on the boundary conditions of the blade–fixture system. Then the finite element analysis (FEA) method is used to simulate the variation trend of preloads, stiffness and blade distortion. The strong influence of parameters of workpiece–fixture configuration on blade distortion and machining error is investigated.

With a case of real jet engine blade machining, the experimental results and theoretical predictions suggest good agreement on their variation tendency. The loaded pressure of clamps has a critical influence on the total stiff performance of the blade–fixture system, and the profile error of the blade contributes much to the inconsistency in geometric dimension and surface integrity of blades’ machining. In the end, the results also validate the effectiveness of this methodology to predict and improve the performance of the blade–fixture configuration design.

The adaptive machining of near-net-shaped jet engine blade is a new high-performance manufacturing technology in aerospace production. This study provides a fundamental methodology for the performance analysis of blade-fixture system, to clear the variation law of blade distortion during preloading and machining, which will contribute to minimize the machining error and improve productivity.

Fixture design is a complicated task requiring both intensive knowledge and experience. This paper aims to present a computer-aided fixture design (CAFD) system framework based on design reuse technology.

Fixture design domain ontology is constructed by analyzing fixture design document corpus. A design reuse engine is proposed to realize fixture design knowledge retrieval and fixture model retrieval based on ontology and find fixture design cases similar to fixture design problem, and then use evolutionary methods to modify the retrieved model to meet the design requirements and then generate a new fixture.

The paper finds that the proposed framework is an efficient tool to improve efficiency of fixture design.

Fixture design existing experience and cases can be used efficiently reused and to advance new fixture design processes.

This paper presents a CAFD system framework capable of carrying out fixture design through full using of the existing fixture design resource and experienced knowledge.

Modular fixture configuration design is a complicated task requiring both intensive knowledge and experience. Automated or semi‐automated computer‐aided modular fixture systems based on computer‐aided design packages do not appear to have made a significant impact within the manufacturing industry. Modular fixture designers still prefer traditional systems such as paper or physical model; as such models provide a more intuitive interaction and immediate feedback. The objective of the paper is to present an application of the desktop virtual reality (VR) to develop an interactive modular fixture assembly design system.

Desktop‐based friendly interface is designed and the low‐system requirement key techniques, namely assembly modeling and collision detection approach, to make proposed system run smoothly on a desktop PC, are presented.

The paper finds that the proposed system is an efficient tool for modular fixture configuration design.

The proposed system is a portable and affordable solution for modular fixture design.

A low‐cost VR application for modular fixture configuration design is presented.

The purpose of this paper is to develop an assembly modelling approach to be applied with a software package, to assist in the design and assembly of special purpose machines (SPMs).

A database of SPM elements was established, and an assembly relationships graph was created. Mating conditions were identified between the SPM elements, and their assembly constraints were extracted and implemented in SolidWorks application programming interface.

The implementation of this assembly modelling approach was validated by selecting SPM layouts as examples. A significant reduction in the assembly time was achieved compared to the traditional assembly procedure for the same examples.

This is a new application of assembly modelling that assists engineers and designers in the design and assembly processes of SPMs. This approach can also be applied to other machine tools with similar attributes.

A fixture is a special tool used to accurately and stably locate the workpiece during machining process. Proper fixture design improves the quality and production of parts and also facilitates the interchangeability of parts, which is prevalent in much of modern manufacturing. The purpose of this paper is to combine the rule‐based reasoning (RBR) and case‐based reasoning (CBR) method for machining fixture design in a virtual reality (VR) based integrated system.

In this paper, an approach combining the RBR and fuzzy comprehensive judgment method is proposed for reasoning suitable locating features and clamping features. Based on the reasoning results, a CBR method for machining fixture design is then presented.

The paper finds that the proposed system is an efficient tool for machining fixture design.

The proposed system enables the designers to perform fixture design with automated fixture locating method reasoning and make a new fixturing solution quickly by referencing previous design cases.

A VR application for machining fixture design is presented.

The purpose of this paper is to clarify the relationship between automated assembly and mass production environments such as the manufacture of cars, airplanes and white goods and methods of modelling and simulation. Even in this environment high‐level automated assembly is restricted to the original equipment manufacturers where production volumes are high and flexibility and the ability to quickly reconfigure systems are not major drivers. It proposes modelling of the fixing/assembly process and outlining why and how new methods are important throughout the manufacturing process. The paper aims to expand the domain of co operation of different research institutes, universities and companies.

The paper focuses on typically, fixture design, which involves the identification of clamp, locator, and support points, and the selection of corresponding fixture elements for their respective functions. In addition, the automation of fixture design activities in manufacturing is an important research area, which aims to achieve the integration of design and manufacturing. The most commonly used methods are pointed out.

The paper summarizes the main modelling and simulation methods applied to new fixing and assembly processes.

Because of the chosen research approach, the paper is more general.

The paper includes implications for the development of a powerful new fixing method applied in the automotive and aerospace industry, which is important for stability and easy change in a rough manufacturing environment.

This paper fulfils an identified need to study how new fixing methods can improve motorcar and aerospace manufacturing.

The virtual design environment offers users an opportunity to interact with a virtual prototyping rather than physical models and to build a fixture configuration in a realistic way. But the virtual reality (VR) environment tends to be inaccurate because humans have difficulty in performing precise positioning tasks. Therefore, it is necessary to implement precise object manipulation methods for assembly and disassembly activities, so that users can perform modular fixture configuration design efficiently in VE. The purpose of this paper is to develop a VR‐based modular fixture assembly design system, which supports the design and assembly of modular fixture configuration in a virtual environment.

Geometric constraint‐based method is utilized to represent and treat the assembly relationship between modular fixture elements. The paper presents a hybrid method of rule‐based reasoning and fuzzy comprehensive judgment to capture the user's operation intent and recognize geometric constraint. Through degrees of freedom based analysis, a mathematical matrix is presented for representing and reducing allowable motion of fixture elements, and a constraint‐based motion navigation approach is proposed to ensure that the manipulation of a fixture component not violate that the existing constraints.

The paper finds that the proposed techniques are applicable to the convenient manipulation and accurate positioning of fixture elements in a virtual environment.

Component manipulation plays a key role in interactive virtual assembly design. The proposed approach in this paper enables interactive assembly design of modular fixture in virtual environment.

This paper presents a geometric constraint‐based approach that realizes automatic assembly relationship recognition, constraint solving and motion navigation for interactive modular fixture assembly design in a virtual environment.

Promoting electric vehicles (EVs) is an effective way to achieve carbon neutrality. If EVs are widely adopted, this will undoubtedly be good for the environment. The purpose of this study is to analyze the impact of network externalities and subsidy on the strategies of manufacturer under a carbon neutrality constraint.

In this paper, the authors propose a game-theoretic framework in an EVs supply chain consisting of a government, a manufacturer and a group of consumers. The authors examine two subsidy options and explain the choice of optimal strategies for government and manufacturer.

First, the authors find that the both network externalities of charging stations and government subsidy can promote the EV market. Second, under a relaxed carbon neutrality constraint, even if the government’s purchase subsidy investment is larger than the carbon emission reduction technology subsidy investment, the purchase subsidy policy is still optimal. Third, under a strict carbon neutrality constraint, when the cost coefficient of carbon emission reduction and the effectiveness of carbon emission reduction technology are larger, social welfare will instead decrease with the increase of the effectiveness of emission reduction technology and then, the manufacturer’s investment in carbon emission reduction technology is lower. In the extended model, the authors find the effectiveness of carbon emission reduction technology can also promote the EV market and social welfare (or consumer surplus) is the same whatever the subsidy strategy.

The network externalities of charging stations and the subsidy effect of the government have a superimposition effect on the promotion of EVs. When the network effect of charging stations is relatively strong, government can withdraw from the subsidized market. When the network effect of charging stations is relatively weak, government can intervene appropriately.

Comparing previous studies, this study reveals the impact of government intervention, network effects and carbon neutrality constraints on the EV supply chain. From a sustainability perspective, these insights are compelling for both EV manufacturers and policymakers.