• Korean Journal of Computational Design and Engineering
• /
• v.4 no.1
• /
• pp.12-18
• /
• 1999

A deformable non-Uniform Rational B-Spline (NURBS) based volume is programed for the force reflecting exoskeleton haptic device. In this work, a direct free form deformation (DFFD) technique is applied for the realistic manipulation. In order to implement the real-time deformation, a nodal mapping technique is used to connect points on the virtual object with the NURBS volume. This geometric modeling technique is ideally incorporated with the force reflecting haptic device as a virtual interface. The results in this work introduce details for the complete set-up for the realistic virtual clay modeling task with force feedback. The force reflecting exoskeleton haptic manipulator, coupled with a supporting PUMA 560 manipulator and the virtual clay model are integrated with the graphics display, and results show that the force feedback from the realistic physically based virtual environment can greately enhance the sense of immersion.

• Journal of the Korean Society for Precision Engineering
• /
• v.16 no.5 s.98
• /
• pp.112-123
• /
• 1999

Virtual reality is becoming a powerful tool for various applications such as training, entertainment, surgery, tele-robotics etc. One potential use for virtual reality is to allow several users to interact in a single virtual environment, for example several students sitting in front of different computers connected over a network. In this paper, we present a loosely coupled architecture of haptic display in the multi-user virtual world. The method of controlling haptic devices as well as the way of configuring individual haptic display system are addressed. We will develop an experimental virtual reality system for two remote users and conclude with an experimental work for the task of a multi-player ping-pong and grasping of a common object.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.26 no.8
• /
• pp.1255-1258
• /
• 2022

Recently, immersive VR/AR contents have actively increased, and various services related to VR/AR allow users to experience remote places. For example, if failure situations occur frequently in factory of the remote site, mixed reality (MR) with a synthetic virtual human expert in reconstructed remote location can help immediate maintenance task with interaction between the operator and the virtual expert. In this paper, we present a technique for synthesizing the virtual human after capturing a 360-degree panorama of a remote environment, and analyze the effects to apply a method of guiding virtual human by interaction types. According to this paper, it was shown that co-presence level significantly increased when verbal, facial expression, and non-verbal animation of the virtual human was all expressed.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.25 no.5B
• /
• pp.899-912
• /
• 2000

PVM provides users with a single image of high performance parallel computing machine by collecting machines distributed over a network. Low communication overhead is essential to effectively run applications on PVM based platforms. In the original PVM, three times of memory copies are required for a PVM task to send a message to a remote task, which results in performance degradation. We propose a zero-copy model using global shared memory that can be accessed by PVM tasks, PVM daemon, and network interface card(NIC). In the scheme, a task packs data into global shared memory, and notify daemon that the data is ready to be sent, then daemon routes the data to a remote task to which it is sent with no virtual data copy overhead. Experimental result reveals that the message round trip time between two machines is reduced significantly in the proposed zero-copy scheme.

• The Journal of Society for e-Business Studies
• /
• v.16 no.4
• /
• pp.283-299
• /
• 2011

In this paper, we draw upon Task-Technology Fit theory to investigate the fit attributes which impacted on customer preference over three virtual shopping channels which included TV home shopping, Internet shopping, and broadband applications, i.e. IPTV. The fit attributes also reflected the product category contingency, which is classified based on the degree of quality assessing difficulty on the web, such as quasi-commodity, look and feel goods, and look and feel with variable quality goods. Using the collected survey data, we employed stepwise regression analysis to validate the fit attributes in the context of performing virtual shopping task via those three distinctive media technologies. Furthermore, through ANOVA test with Duncan statistics, we reported comparative intensity of the valid fit attributes across the product categories and distinct media technologies. The results validated four critical fit attributes and significant distinctions among product categories and three virtual shopping channels. The findings provide practical insights in distribution channel design exploiting digital convergence technologies.

• International Journal of Precision Engineering and Manufacturing
• /
• v.1 no.1
• /
• pp.84-90
• /
• 2000

The importance of Virtual Manufacturing System is increasing in the area of developing new manufacturing processes, implementing automated workcells, designing plant facility layouts and workplace ergonomics. Virtual manufacturing system is a computer system that can generate the same information about manufacturing system structure, states, and behaviors as is observed in a real manufacturing. In this research, a virtual manufacturing system for flexible manufacturing cells (VFMC), (which is a useful tool for building Computer Integrated Manufacturing (CIM), has been developed using object-oriented paradigm, and implemented with software QUEST/IGRIP. Three object models used in the system are the product model, the facility model, and the process model. The concrete behaviors of a flexible manufacturing cell are re[presented by the task-oriented description diagram, TIC. An example simulation is executed to evaluate applicability of the developed models, and to prove the potential value of virtual manufacturing paradigm.

• 제어로봇시스템학회:학술대회논문집
• /
• 2000.10a
• /
• pp.103-103
• /
• 2000

In this paper to cope with the reduction of products life-cycle as the variety of products along with the various demands of consumers, a virtual simulator is developed to make the changeover of manufacturing line efficient to embody a virtual simulation similar to a real manufacturing line. The developed virtual simulator can design a layout of a factory and make the time scheduling. Every factory has one simulator so that one product can be manufactured in the factories to use them as virtual factories. We suggest a scheme that heightens the agility to the diversity of manufacturing models by making the information of manufacturing lines and products models to be shared. The developed unit simulator can construct a proper virtual manufacturing line along with the required process of products using several kinds of operator and work cell. A user with the simulator can utilize an interface that makes one to manage the separate task process for each manu(acturing module, change operator components and work cells, and easily teach tasks of each task module. The developed simulator was made for users convenience by Microsoft Visual C++ 6.0 that can develop a program supplying graphic user interface environment and by OpenGL of the Silicon Graphics as a graphic library to embody 3D graphic environment. Also, we show that the simulator can be used efficiently for the agile manufacturing by the communication among the factories being linked by TCP/IP and a hybrid database system made by a hierarchical model and a relational model being developed to standardize the data information.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.25 no.5
• /
• pp.891-898
• /
• 2001

This paper develops a master manipulator which can reflect a force from a slave manipulator effectively. It many have a big workspace, can represent a human operators manipulation perfectly, and is composed of a position control part, an orientation control part and an end effector control part. This paper also develops a graphic simulator using the Visual C++ and OpenGL in the Window operating system. It can be used to make a virtual slave manipulator and set a virtual working environment, and provide a visual information from a desired view point. A virtual teleoperation system is developed by connecting the developed master manipulator to the graphic simulator using an interfacing hardware bilaterally. It is used for performing a virtual object exploration experiment. In the experiment, two virtual objects are used. They are virtual wall and virtual hexahedron which have 0.7N/mm and 2.2 N/mm stiffness respectively. The experiments are performed under six different working conditions. The experiment results will show the effectiveness of the reflected force from the slave manipulator for improving the efficiency and stability of the teleoperation task.

• Journal of the Institute of Electronics Engineers of Korea SC
• /
• v.41 no.6
• /
• pp.1-10
• /
• 2004

A haptic rendering system is proposed for a puncture task of a virtual vertebra model. To build a mesh model from medical images, Delaunay triangulation is applied and physical models are based on elasticity theory. Also, a redundant actuated 6 DOF parallel type haptic device is designed to display large force and to resolve the singularity problem of parallel type mechanisms. Haptic feeling of puncture task and the performance of the proposed haptic device are tested by two puncture task experiments.

• Korean Management Science Review
• /
• v.18 no.1
• /
• pp.55-68
• /
• 2001

A virtual shopping mall is like a real-world mall, supports electronic shopping by selling products or services through Interne. Although increasing numbers of products are being marketed on the Web, little efforts has been spent on evaluating what mall is more suitable for marketing electronically and for protecting consumers. Evaluation of virtual shopping malls is regarded as a major task in business-to-consumer electronic commerce. This paper considers the Analytic Hierarchy Process(AHP) method in the evaluation of virtual shopping malls and provides its applications. The AHP is a systematic procedure for representing the elements of any problem, hierarchically. A series of pairwise comparison judgments is performed to express the relative strength or intensity of impact of the elements in the hierarchy. The AHP model hierarchy consists of the four following levels: decision maker, main criteria, sub-criteria, and virtual shopping malls. the main criteria include the state of physical firms, representation of information on the virtual shopping malls, product or service, convenience for shopping, consumer protection, and consumer service. The total number of sub-criteria in the third level is twenty-nine. All decision makers selected belong to virtual shopping mall enterprises, or universities. As a case study, we show the synthesized priority of the five virtual shopping malls that have acquired an E-Trust mark. Finally a sensitivity analysis shows how well each virtual shopping mall performs on each criterion by increasing or decreasing the importance of the main criteria.