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This paper aims to report the development and key features of a novel virtual reality system for assembly planning and evaluation called Haptic Assembly and Manufacturing System (HAMS). The system is intended to be used as a tool for training, design analysis and path planning.

The proposed system uses the physics-based modelling (PBM) to perform assemblies in virtual environments. Moreover, dynamic assembly constrains have been considered to reduce the degrees of freedom of virtual objects and enhance the virtual assembly performance.

To evaluate the effectiveness and performance of HAMS, the assembly of various mechanical components has been carried out, and the results have shown that it can be effectively used to simulate, evaluate, plan and automatically formalise the assembly of complex models in a more natural and intuitive way.

The collision detection performance is the bottleneck in any virtual assembly system. New methods of collision shape representation and collision detection algorithms must be considered.

HAMS introduces the use of dynamic assembly constraints to enhance the virtual assembly performance. HAMS also uses features not yet reported by similar systems in the literature. These features include: automatic or manual definition of assembly constraints within the virtual assembly system; the implementation of control panels and widgets to modify simulation parameters during running time to evaluate its influence on simulation performance; assembly data logging such as trajectories, forces and update rates for post-processing, further analysis or its presentation in the form of chronocyclegraphs to graphically analyse the assembly process.

The paper aims to present the processing pipeline of an assembly immersive simulation application which can manage the interaction between the virtual scene and user using stereoscopic display and haptic devices. A new set of elements are integrated in a Collaborative Virtual Environment (CVE) and validated using an approach based on subjective and objective users’ performance criteria. The developed application is intended for Assembly/Disassembly (A/D) analysis, planning and training.

A mobility module based on contact information is used to handle the assembly components’ movements through real-time management of collision detection and kinematically constraint guidance. Information on CVE architecture, modules and application configuration process are presented. Impact of device type (3 degrees of freedom (DoFs) vs 6 DoFs) over user’s experience is evaluated. Parameters (number of assembled components and components assembly time) are measured for each user and each haptic device, and results are compared and discussed.

Test results proved the efficiency of using a mobility module based on predefined kinematic constraints for reducing the complexity of collision detection algorithms in real-time assembly haptic simulations. Also, experiments showed that, generally, users performed better with 3 DoFs haptic device compared to 6 DoFs haptic equipment.

The proposed immersive application automates the kinematical joints inference from 3D computer-aided design (CAD) assembly models and integrates it within a haptic-based virtual environment, for increasing the efficiency of A/D process simulations.

This paper aims to investigate empirically the findings of an analytical impure public good model. The impure public good model described in this study allows for the application of different technologies generating public and private characteristics. The influence of the individual technologies on the total level of (impure) public good provision is of main concern in this study.

After the illustration of the impure public good model, the analytical results are compared to the results of a numerical approach based on climate policy in Germany.

The study shows that comparative static analyses do not always generate clear results. Therefore, the numerical approach is helpful to derive unambiguous results. The paper finds that technologies which exclusively generate private characteristics may have significant effects on total impure public good provision, since they may replace the private characteristics of the impure public good.

This paper provides useful information on the influence of the individual technologies on the total level of (impure) public good provision.

This study aims to present a new haptic-enabled virtual assembly system for the automatic generation and objective assessment of assembly plans. The system is intended to be used as an assembly planning tool along the product development process.

The generation of product assembly plans is based on the analysis of the assembly movements and operations performed by the user during the virtual assembly execution, and the objective assessment of product assembly is based on the definition and computation of new proposed assembly metrics.

To evaluate the system, a case study corresponding to the assembly of a mechanical component is presented and analyzed. The results demonstrate that the proposed system is an effective tool to plan and evaluate different product assembly strategies in a more practical and objective approach than existing assembly planning methods.

Although the virtual assembly execution time is larger than the real assembly execution time, the assembly planning and evaluation results provided by the system are valid. However, the development of higher performance collision detection algorithms is needed to reduce the simulation time.

The proposed virtual assembly system is able to not only simulate and automatically generate assembly plans but also objectively assess them from the virtual assembly task execution. The introduction and use of several assembly performance metrics to objectively evaluate assembly strategies in virtual assembly also represents a novel contribution.

Haptics can significantly enhance the user's sense of immersion and interactivity. Especially in an assembly task, haptic feedback can help designers to have a better understanding of virtual objects and to increase task efficiency. The purpose of this paper is to investigate the design and implementation of a haptic‐based virtual assembly system (HVAS).

A multi‐thread system structure was designed, an automatic data integration interface was developed to transfer geometry, topology, assembly and physics information from a computer‐aided design system to virtual reality application, and a hierarchical constraint‐based data model and scene graph structure was designed to construct the virtual assembly environment. Unlike traditional virtual assembly systems based on collision detection or geometry constraint only, a physics‐based modeling approach combining with haptic feedback and geometry constraint was undertaken to realize and guide the realistic assembly process. When two parts collide into each other, the force and torque can be computed and provide feedback, and a spring‐mass model is used to prevent penetration and simulate dynamic behaviour. When two parts are close enough to each other and the assembly simulation state is activated, a geometry constraint can be captured, an attractive force can be generated to guide the user to assemble the part along the correct position, and the repulsive force can also be generated to realize the mating process as natural and realistic as in real life.

The implementation details and application examples demonstrate that haptic‐based virtual assembly is a valuable tool for assembly design and process planning.

The paper presents an HVAS.

The study aims to explore and explain the affordances and constraints of two-mode virtual collaboration as experienced by a newly forming international research team.

This is self-reflective and action-oriented research on the affordances and constraints of two-mode virtual collaboration. In the spirit of professional development, the authors (nine researchers at different career stages and from various counties) engaged in a joint endeavour to evaluate the affordances and constraints of virtual collaborations in light of the recent literature while also researching the authors' own virtual collaboration during this evaluative task (mid-January–April 2021). The authors used two modes: synchronous (Zoom) and asynchronous (emails) to communicate on the literature exploration and recorded reactions and emotional responses towards existing affordances and constraints through a collective journal.

The results suggest both affordances in terms of communication being negotiable and evolving and constraints, particularly in forming new relations given tools that may not be equally accessible to all. Journaling during collaborations could be a valuable tool, especially for virtual collective work, because it can be used to structure the team supported negotiation and discussion processes, especially often hidden processes. It is evident that the role of a leader can contribute to an alignment in the assumptions and experiences of trust and consequently foster greater mutual understanding of the circumstances for productive team collaborations.

The findings of this study can inform academics and practitioners on how to create and facilitate better opportunities for collaboration in virtual teams as a rapidly emerging form of technology-supported working.

This paper introduces an alternative teaching model in a virtual architectural design studio, its application, impacts and constraints. This model aims for achieving collaborative learning through facilitating students to Inhabit, Design, Construct and Evaluate (IDCE) their designs collaboratively in a multi-user real-time 3D virtual environment platform (Activeworlds). The application of this model in virtual design studio (VDS) teaching has favorably impacted students' motivation for active, creative and explorative learning, social dynamics between studio participants. It also fostered learning electronic communication, collaboration techniques and etiquette in addition to design technology. The model assisted in developing collaborative experience and shared responsibility. However, there are some drawbacks of the virtual environment platform that hindered having a responsive design environment to users' needs with especially in modeling and rate of viewing. The advantages and constraints of applying the IDCE teaching model in a multi-user real-time 3D virtual environment for first year students at the University of Sydney are addressed in this paper.

The purpose of this paper is to give a comprehensive survey on the physics-based virtual assembly (PBVA) technology in a novel perspective, to analyze current drawbacks and propose several promising future directions.

To provide a deep insight of PBVA, a discussion of the developing context of PBVA and a comparison against constraint-based virtual assembly (CBVA) is put forward. The core elements and general structure are analyzed based on typical PBVA systems. Some common key issues as well as common drawbacks are discussed, based on which the research trend and several promising future directions are proposed.

Special attention is paid to new research progresses and new ideas concerning recent development as well as new typical systems of the technology. Advantages of PBVA over CBVA are investigated. Based on the analysis of typical PBVA systems and the evolution of PBVA, the core elements of the technology and the general structure of its implementation are identified. Then, current PBVA systems are summarized and classified. After that, key issues in the technology and current drawbacks are explored in detail. Finally, promising future directions are given, including both the further perfecting of the technology and the combination with other technologies.

The PBVA technology is put into a detailed review and analysis in a novel way, providing a better insight of both the theory and the implementation of the technology.

The purpose of this paper is to investigate whether virtual space can be used to alleviate physical space constraints for group collaboration in an urban academic library environment. Specifically, this paper looks to uncover whether library users will turn to library‐provided virtual space when there is a scarcity of physical space.

This project discusses the design of the physical and virtual environment, and then measures the use of this environment quantitatively over a 47‐month period (2005‐2009).

Results indicate that physical spaces for group collaboration are in very high demand, whereas virtual ones are not. A scarcity of physical collaboration spaces does not lead users to library‐provided virtual space, but rather to work around the scarcity in the physical world.

The paper highlights the value of the library as a gathering place and the ways in which virtual collaboration space cannot easily take the place of physical collaboration space.

Virtual reality (VR) for product assembly has been studied for more than 20 years but its practical application in industry is still very much in its infancy. Haptics is a new and important interaction method for VR and a strong and growing research area, however, it still remains a virtually unknown concept for industrial application.

This paper provides a comprehensive survey of VR and haptics for product assembly, from rigid parts to soft cables.

Some new ideas and research progresses in recent years are especially investigated. First the concepts and classifications of virtual assembly are introduced and the different virtual environment systems for product assembly are discussed. Then the major research groups, typical systems and major research issues are explored in detail, treating rigid parts and soft cables separately. Lastly, the barriers preventing successful application of virtual assembly are discussed and future research directions are also summarized.

The paper provides an overview and analysis of VR and haptics for product assembly, including both rigid parts and soft cables.