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Large-scale mobile radars are still erected manually by using lifting equipment, which often fails to meet the requirements on precision, quality and efficiency in the erecting process. This paper aims to introduce techniques for automatic assembly of large mobile radar antenna.

A large-scale metrology system for accurate identification of the positions and orientation of the radar antenna components is presented. A novel three-degree-of-freedom parallel mechanism is designed to realize orientation adjustment of three axes synchronous, and, thus guarantees the efficiency and accuracy of positioning process.

The system described in this paper is practicable in outdoor environment and provides a holistic solution that gives full consideration of the operation conditions and the environmental influences. In performance evaluation tests, the measured absolute accuracy is less than ±1 mm and repeatability is less than ±0.5 mm in the positioning task for 10 × 3 m large antenna.

This paper presents a new concept of an automatic assembly technology for the large radar antenna application.

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.

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 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.

Maintainability is the ability of a product system to be maintained and is a design characteristic. The paper aims to provide an integrated system for complex product maintainability design and verification. It includes processes and tools that can be effectively used to plan, quantify and cost maintenance.

An integrated platform for maintainability design and verification is designed. A case‐based reasoning method of maintainability design and Extensible Markup Language‐based representation of maintenance procedure information are presented.

The paper finds that the proposed system is an efficient tool for complex product maintainability design and verification.

Early and effective planning and implementation of a maintainability program can significantly improve the reliability and availability of product system.

A desktop virtual reality application for product maintainability design and verification is presented.

As an important product characteristic, maintainability is recognized as a highly significant factor in the economic success of engineering systems and products. Based on virtual reality technology, this paper aims to create an intuitive, immersive and interactive environment for product maintenance. In order to analyze and evaluate the product maintainability in a virtual maintenance environment, fuzzy comprehensive evaluation is used. At the early design stage, maintainability influencing factors are analyzed and the whole maintainability evaluation of the product is given by using fuzzy comprehensive evaluation method in virtual maintenance environment.

The paper provides a fuzzy comprehensive evaluation method for product maintainability evaluation in virtual environment.

Fuzzy comprehensive evaluation is used to evaluate product maintainability in virtual environment, and the application of virtual maintainability system is expanded.

According to maintainability requirement, the maintainability index set is built in this paper, and fuzzy comprehensive evaluation method is used to evaluate product maintainability in virtual maintenance environment at stage of early design.

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 provide a new approach involving guidelines and supporting techniques that guarantees all needed space for appropriate product maintenance.

The approach is based on two major areas: field survey to understand how maintainability parameter is applied and converge theory and practice into a systematic space claim method using computer-aided design (CAD) systems to assure proper maintenance procedures at design stages.

Case studies from a truck industry conducted following the proposed approach contrast the savings that can be achieved by using a proper space claim for aftermarket needs against an unsuitable level of participation by maintenance personnel during the design development.

This approach is highly dependent on maintenance experts with suitable skills on CAD systems.

Products developed according to the approach envisaged can result in following aspects: lower repair time, better maintenance procedures on key components, easier preventive maintenance, less need for special tools, more ergonomic design, better communication between design and service engineers, simplicity and less complex training.

Further research on maintainability will provide new information on how to apply this parameter on product development process (PDP), so design teams can better understand and address this relevant issue. The proposed method has been introduced in the PDP of a major multinational automotive company.

A new process is presented, considering the protection of needed spaces for maintenance procedures throughout the PDP, diverging to other studies that only propose analysis addressing maintainability at singular point in time during the product development. In just one case study presented, savings of US$1.3m were achieved by applying this space claim approach.

Maintainability, as an intrinsic property that shows how well a product can be maintained, should be strictly controlled in the design stage. Maintenance space is an important aspect of maintainability and should be verified in the design stage. Methods to verify maintenance space based on expert knowledge or vision cone have been proposed. However, no proper quantitative solutions have been proposed yet to verify maintenance space in the design stage. This paper aims to provide a new method to evaluate quantitatively the maintenance space in a virtual environment by using the swept volume (SV).

An integrated platform for quantitatively evaluating maintenance space in a virtual environment is designed. Virtual reality technology and digital prototype are used to overcome the shortage of physical prototypes in the design stage. SVs are applied to represent the movement of the hand along the entire maintenance process. Maintenance operations are divided into three basic types. Each type of basic operation refers to two quantitative indexes, namely the surface area and the volume of the SV of the maintenance personnel. Data on the indexes are gathered and calculated to evaluate maintenance space.

The proposed methodology can evaluate feasibly and efficiently the maintenance space determined by the layout design of product components in the design stage.

Application of the proposed method can help designers reduce the shortness of maintenance space and improve the design layout of products.

A method to evaluate maintenance space that employs a quantitative combination of virtual environment and swept volume is pressed.