• Journal of Auto-vehicle Safety Association
• /
• v.7 no.1
• /
• pp.33-39
• /
• 2015

This study examined the drivers' acceptance level of various active safety features with Korean drivers on Seoul urban and city roads. The test vehicle, 2013 Cadillac ATS, was equipped with FCA(Forward Collision Alert), LDW(Lane Departure Warning), SBZA(Side Blind Zone Alert), FRPA(Front/Rear Park Assist), RCTA(Rear Cross Traffic Alert), ACC(Adaptive Cruise Control), and AEB(Autonomous Emergency Braking). Participants had chances to run the tests on those systems in the parking lot accompanied by the 106km long stretch of predetermined route including local road and interurban highway in Seoul and Gyeonggi-do under normal traffic flowing environment. After the test, participants completed a series of questionnaires about the features they experienced. The results revealed that RCTA and SBZA systems received more favourable ratings compared to the other features in avoiding crashes. The respondents preferred sound alerts to haptic ones even though haptic warning methods were better in providing directional information.

• Journal of the Korea Computer Graphics Society
• /
• v.26 no.3
• /
• pp.79-86
• /
• 2020

It is important to exercise in the correct posture in order to increase the exercise effect of the core exercise. This paper introduces a system that can train an exercise posture by providing feedback so that a user who performs core exercise in a virtual reality environment can take an accurate posture. It targeted three core movement postures, such as squat, lunge, and bridge, and provides visual feedback and haptic feedback to the user to take an accurate posture. The reference posture is generated by adjusting the expert's posture to the user's body length, and the accuracy of the exercise posture is calculated by comparing the user's posture with the reference posture. The effectiveness of the feedback was verified through user experiments, and the training effects according to the design of the feedback were compared.

• Journal of the Ergonomics Society of Korea
• /
• v.32 no.4
• /
• pp.355-361
• /
• 2013

Objective: The aim of this study is to investigate the gender-differences in vibrotactile responses(sensitivity and displeasure) of residual forearm simulated by vibration stimulation in upper limb(trans-radial) amputees. Background: Several studies have reported that vibration stimulation using the haptic vibrator is one the most effective methods for delivering sensation to an amputees. However, few studies have reported the perception to haptic vibratory stimulus, particularly sensitivity and displeasure. Method: We set up a custom-made vibration stimulation system that included 6 actuators(3 medial parts and 3 lateral parts) and a graphical user interface(GUI)-based acquisition system to investigate changes in residual somatosensory sensibility and displeasure in the forearm of upper limb(trans-radial) amputees. Vibration actuators were attached at the 25%-point on the proximal forearm. Stimulation with 32Hz, 64Hz, or 149Hz of frequency was used for the sensitivity tests and with 32~257Hz of frequency was used for the discomfort experiments. The subjective responses were evaluated on a 10 point scale. Results: The results showed that vibrotactile sensory perception in male amputees were higher than that in female amputees. In male amputees, the response at lateral area of forearm was the most sensitive than medial area; but, female amputees showed similar sensitive areas. Subjects did not experience any discomfort during vibrotactile stimuli. Conclusion: Vibrotactile response in the amputees was dependent on gender as well as area stimulated by vibration. Application: The results might contribute to develop the vibrotactile feedback system for the amputees.

• The Journal of Korean Academy of Prosthodontics
• /
• v.49 no.4
• /
• pp.354-361
• /
• 2011

There are still many limitations on fabricating dentures using digital method while computerized production of fixed prostheses utilizing intraoral scanner and CAD/CAM technology has propagated rapidly. Recently the digital solution of fabricating removable partial denture by applying haptic input device, electronic surveying, and rapid prototyping was introduced. In this case presentation, five patients were treated with surveyed crown and removable partial dentures by this digital solution. Fit of dentures was excellent except for one case which showed morphological difference between the actual teeth and that of master cast by the erroneous impression process. There also was not any problem of stability and retention after adaptation in the clinical setting.

• Journal of the Korea Society of Computer and Information
• /
• v.17 no.12
• /
• pp.209-217
• /
• 2012

In this paper, I proposed new system that a user makes modeling 3D symmetric pottery using mouse and can confirm the result immediately in internet browser. The main advantage of proposed system is that users who have no specialized knowledge about 3D graphic can easily create 3D objects. And a user can use it that has only PC connected network and mouse without additional devices as like expensive haptic and camera device. For developing proposed system, VRML/X3D that is International Standard language for virtual reality and 3D graphics was used. Because it was born based on internet that is different from other 3D graphic languages, it was able to interact and navigate with users. With those features and high completeness of 3D pottery realization using mouse considered, the system may be useful and is superior in performance to other pottery modeling system.

• Journal of the Korea Convergence Society
• /
• v.9 no.11
• /
• pp.291-297
• /
• 2018

Due to difficulty in minimally invasive surgery, training simulator is actively researched. A volumetric deformable organ is created by employing a shape-retaining chain-linked (S-chain) model to realize positioning a human organ model in virtual space. Since the main principle of the S-chain algorithm is that the repulsive force is proportional to the number of chain elements, the calculation time can be increased according to the magnitude of deformation. In this work, the advanced S-chain algorithm is used to calculate the repulsive torque according to spin motion. Finally, haptic architecture was constructed using this S-chain model by incorporating the virtual organ with a real master device, which allows the repulsive force and target position to be transferred to each other. The control performance of S-chain algorithm has been evaluated via experiment.

• Convergence Security Journal
• /
• v.18 no.4
• /
• pp.62-71
• /
• 2018

The rapid growth of virtual reality technology in the era of the 4th Industrial Revolution has accelerated scientification of combat training systems in addition to ICT(information and communications technology) in military field. Recently, research and development of simulators based on virtual reality have been actively conducted in order to solve sensitive issues such as increase of civil complaints due to the noise of a shooting range, prevention of shooting accident, and reduction of training cost. In this paper, we propose two key solutions: spatial synchronization method and modified point mass trajectory model with small angle approximation to overcome technical limitations of a current training simulator. A trainee who wears a haptic vest in a mixed reality environment built in MARS(medium-range assault rifle shooting simulator) is able to conduct not only precision shooting but also two-way engagement with virtual opponents. It is possible for trainee to receive more reliable evaluations in the MARS than an existing rifle simulator based on laser.

• Journal of Internet Computing and Services
• /
• v.25 no.1
• /
• pp.9-15
• /
• 2024

As virtual reality technology became popular, a high demand emerged for natural and efficient interaction with the virtual environment. Mid-air manipulation is one of the solutions to such needs, letting a user manipulate a virtual object in a 3D virtual space. In this paper, we focus on manipulating a remote virtual object while visually displaying the object and providing tactile information on the object's weight. We developed two types of wearable interfaces that can provide cutaneous or vibrotactile feedback on the virtual object weight to the user's fingertips. Human perception of the remote virtual object weight during manipulation was evaluated by conducting a psychophysics experiment. The results indicate a significant effect of haptic feedback on the perceived weight of the virtual object during manipulation.

• The Journal of Sustainable Design and Educational Environment Research
• /
• v.13 no.1
• /
• pp.24-31
• /
• 2014

This study is focused to find the ways to improve the effective BIM introduction plan on school building construction by Delphi Technique. For this, the questionnaire is made by in-depth interviews of 10 BIM specialists, the survey of other 30 experts was carried out. The results of 30 experts Delphi survey are as followed. (1) The haptic effect of BIM introduction is very rare as lack of awareness and information on BIM. (2) Problems are arising from deficiency of training and experience on BIM. (3) Practical utilizations of BIM are very useful. (4) Barriers of the spread of BIM are high cost and insufficient environments. (5) The development potential of BIM is high. In order to activate the BIM market, the introduction of an accurate evaluation criteria and rational cost calculation standard are needed.

• The Journal of the Korean dental association
• /
• v.50 no.3
• /
• pp.140-147
• /
• 2012

Recently, the digital solution of fabricating removable prosthesis by applying haptic input device, electronic surveying, and rapid prototyping was introduced. This review article covers the concept of electronic surveying, computer-aided denture framework designing procedure, discussions after several digital denture cases, directions of future development, such as digital tooth arrangement and RP flasking.