• Title/Summary/Keyword: Visual force

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Internet-based Teleoperation of a Mobile Robot with Force-reflection

  • Lim, Jae-Nam;Moon, Hae-Gon;Ko, Jae-Pyung;Lee, Jang-Myung
    • 제어로봇시스템학회:학술대회논문집
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    • 2002.10a
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    • pp.50.6-50
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    • 2002
  • In this paper, the relationship between a slave robot and the uncertain remote environment is modeled as the impedance to generate the virtual force to feed back to the operator. For the control of a teleoperated mobile robot equipped with camera, the teleoperated mobile robot take pictures of remote environment and sends the visual information back to the operator over the Internet. Because of the limitation of communication bandwidth and narrow view-angles of camera, it is not possible to watch the environment clearly, especially shadow and curved areas. To overcome this problem, the virtual force is generated according to both the distance between the obstacle and robot and the approachin...

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Nanolithography Using Haptic Interface in a Nanoscale Virtual Surface (햅틱인터페이스를 이용한 나노스케일 가상표면에서의 나노리소그래피)

  • Kim Sung-Gaun
    • Journal of the Korean institute of surface engineering
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    • v.39 no.2
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    • pp.64-69
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    • 2006
  • Nanoscale task such as nanolithography and nanoindenting is a challenging work that is beyond the capabilities of human sensing and precision. Since surface forces and intermolecular forces dominate over gravitational and other more intuitive forces of the macro world at the nanoscale, a user is not familiar with these novel nanoforce effects. In order to overcome this scaling barrier, haptic interfaces that consist of visual and force feedback at the macro world have been used with an Atomic Force Microscope (AFM) as a manipulator at the nanoscale. In this paper, a nanoscale virtual coupling (NSVC) concept is introduced and the relationship between performance and impedance scaling factors of velocity (or position) and force are explicitly represented. Experiments have been performed for nanoindenting and nanolithography with different materials in the nanoscale virtual surface. The interaction forces (non contact and contact nanoforces) between the AFM tip and the nano sample are transmitted to the operator through the haptic interface.

Design of Boat Racing Game using Buoyant Force

  • An, Syoungog;Kang, Jae-Hyun;Kim, Soo Kyung
    • Journal of the Korea Society of Computer and Information
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    • v.23 no.9
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    • pp.21-26
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    • 2018
  • A variety of game algorithms have been proposed in recent years. Racing games using these new algorithms have greatly improved compared to those in the past. According to the analysis of racing games done by wheelgamer.com, a website that specializes in racing games, cars are the most common subject in mainstream racing games. These results show there are very few racing games using special subjects such as boats. This paper proposes a method to develop a realistic boat racing game using the Buoyont Force, beyond the limitation of typical racing games that are restricted to cars. A Material Editor based on Unreal Engine 4.12 is used to manifest the Dynamic Material of realistic ocean water. Blueprint, a visual scripting function, is used to materialize buoyancy which allows the boat to move freely along the waves.

Effects of Step Length Change on Kinetic Characteristics While Stepping Over an Obstacle From a Position of Quiet Stance in Young and Elderly Adults: A Preliminary Study

  • Kim, Hyeong-Dong
    • Physical Therapy Korea
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    • v.14 no.4
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    • pp.66-74
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    • 2007
  • The aim of the present study was to investigate age-related differences in stepping behavior in response to sensory perturbations of postural balance. The participants for this study were 2 healthy elderly adults (mean age=76.0) and 2 younger adults (mean age=25.5). Subjects were asked to step over a 10 cm high obstacle at self-paced speed with the right limb to land on the primary target (normal step length) that is 10 cm in diameter. However, if, during movement, the light was illuminated, then the subject had to step on the secondary target (long step length). It was planned that the onset of the light would be prior to peak Fx of swing limb, between swing peak Fx and swing toe-off, and after swing toe-off. In the younger adults these secondary visual cues were provided at mean times of 240 ms (standard deviation (SD)=11), 402 ms (SD=13), and 476 ms (SD=88) following the movement onset. Corresponding mean times for the healthy elderly were 150 ms (SD=67), 352 ms (SD=39), and 562 ms (SD=115). Results showed great changes in both group and visual cue condition in Fx ground reaction forces and temporal events following the swing toe-off. Swing limb acceleration force (Fx) and stance peak Fx1 was much greater in the young adults compared to the older adults. Both young and older adults increased stance peak Fx2 in the visual cue condition compared to normal stepping. There was no difference in stance peak Fx2 between the visual cue conditions in both groups. Similarly, the time to stance peak Fx2 was much longer for the visual cue condition than for the normal stepping. It was not different between the visual cue conditions in the young adults, but in the elderly mid and late cue was much greater than early cue. In addition, time to stance peak Fx2 and swing and stance time were much longer in the older adults compared to the young adults for the visual cue conditions. These results suggest that unlike young adults, elderly adults did not flexibly modify their responses to unexpected changes in step length while stepping over obstacles.

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The Effect of Visual Biofeedback on EMG Activity of Trunk Muscles and Endurance Holding Time for Correct Position During Whole-Body Tilt Exercise (전신 기울기 운동 시 시각적 바이오피드백이 올바른 자세 유지 시간과 체간 근육의 근활성도에 미치는 영향)

  • Kang, Min-Hyeok;Yoon, Ji-Yeon;Yang, Jae-Lak;Jang, Jun-Hyeok;Jung, Doh-Heon;Oh, Jae-Seop
    • Physical Therapy Korea
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    • v.18 no.1
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    • pp.9-17
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    • 2011
  • The purpose of this study was to assess visual biofeedback's influence on trunk muscles' (EMG) activity and endurance holding time for correct position during whole-body tilt exercise. For the study, we recruited 14 volunteers who showed no symptom of lumbar disease during medical tests. We measured the EMG activity of their rectus abdominis, external abdominal oblique, internal abdominal oblique and erector spinae muscles, and their endurance holding time for correct position during $40^{\circ}$ anterior and posterior whole-body tilt under two conditions: whole-body tilt with and without visual biofeedback. Resistance with gravitational force on the trunk during whole-body tilt was applied by using a device that had a monitor on which the subjects could check their alignment and that sounded an alarm if a subject's alignment collapsed. The study showed an increase in the EMG activity of external abdominal oblique, internal abdominal oblique/rectus abdominis ratio and endurance holding time for correct position during both $40^{\circ}$ anterior and posterior whole-body tilt with visual biofeedback compared with without visual biofeedback (p<.05). We suggest that the whole-body tilt exercise with visual biofeedback could be a beneficial strategy for selectively strengthening the internal abdominal oblique muscle and minimizing the rectus abdominis muscle's activity while maintaining correct alignment during whole-body tilt exercise.

Visual Search Models for Multiple Targets and Optimal Stopping Time (다수표적의 시각적 탐색을 위한 탐색능력 모델과 최적 탐색정지 시점)

  • Hong, Seung-Kweon;Park, Seikwon;Ryu, Seung Wan
    • Journal of Korean Institute of Industrial Engineers
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    • v.29 no.2
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    • pp.165-171
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    • 2003
  • Visual search in an unstructured search field is a fruitful research area for computational modeling. Search models that describe relationship between search time and probability of target detection have been used for prediction of human search performance and provision of ideal goals for search training. Until recently, however, most of models were focused on detecting a single target in a search field, although, in practice, a search field includes multiple targets and search models for multiple targets may differ from search models for a single target. This study proposed a random search model for multiple targets, generalizing a random search model for a single target which is the most typical search model. To test this model, human search data were collected and compared with the model. This model well predicted human performance in visual search for multiple targets. This paper also proposed how to determine optimal stopping time in multiple-target search.

A Study on the Aesthetic Consciousness in the late Modernism Fashion (모더니즘 후기 복식에 표현된 미의식 연구)

  • 김정은;정흥숙
    • Journal of the Korean Society of Costume
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    • v.51 no.6
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    • pp.67-83
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    • 2001
  • The purpose of this study is to define the aesthetic consciousness in the late Modernism fashion which generated a sudden style change and craze, and to identify the essential meaning of the style. In order to achieve this the aesthetic approach was applied. Visual commonalities were sought between fashion and contemporary architecture, furniture, ceramic and metalware, to lead to a deeper insight into the aesthetic consciousness. Common visual characteristics are curvedness of the line, obliqueness of the line, asymmetry of the form, exaggeration of the form and symbolic nature of the form. The content which can be analogized from the visual characteristics are the beauty of the nature, the beauty of the glamourous feminity, the beauty of the ideal and the beauty of the creative personality. In the creating process, the existential aspect of human being became a focus of attention, and human being's subjectivity operated as a principal force. In the late Modernism fashion, the appreciator's aesthetic experience became more important, and the appreciator's psychological satisfaction and pleasure were considered in the creative process. Fashion, architecture and crafts, which fulfill functional duties in everyday life, facilitated the appreciator's aesthetic experience through empathy. This study inquires into the relationship between aesthetic consciousness and visual form. This study offers meaning because to uncover the connoted aesthetic consciousness in the late Modernism fashion is to pursue the roots of current aesthetic consciousness and it is hoped that in doing so this study will provide a basis for interpreting and understanding today's fashion style.

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Effect of Vision Coherent Sensory Cue on Roll Tilt Perception and Sensory Weighting (족부 진동 자극 유무에 따른 인체의 운동지각 변화 및 정량화)

  • Lim, Hye-Rim;Park, Su-Kyung
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.36 no.11
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    • pp.1091-1097
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    • 2012
  • Nowadays, some movie theaters provide additional sensory information in 3D movies to enhance visually induced motion perception. However, no studies have investigated how motion perception increases. Thus, in this study, we examined the effect of visual coherent sensory information on visually induced motion perception and quantification of sensory information. A visual stimulus rotated sinusoidally and visual coherent sensory information were applied as vibrations to a subject's foot. We measured the sway of the subject's body by using a force plate and somatosensory bar rotation that represents the subject's perception of the horizon using an encoder. By using this data, we obtained the weight of the sensory information using a Kalman filter. As a result, it was found that subjects rotated the somatosensory bar more when visual coherent vibrations were applied. The weight of vision also increased when visual coherent vibrations were applied. Thus, we can conclude that visual coherent sensory information tends to enhance visually induced motion perception and weight of vision.

The Mechanism and Detection of Tool Fracture using Sensor Fusion in Cutting Force and AE Signals for Small Diameter Ball-end Milling (미세 볼엔드밀가공시 절삭력과 음향방출신호에 의한 공구 파손 검출 및 메커니즘)

  • Wang, Duck-Hyun;Kim, Won-Il;Lim, Jeong-Suk
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.3 no.3
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    • pp.24-31
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    • 2004
  • A successful on-line monitoring system for conventional machining operations has the potential to reduce cost, guarantee consistency of product quality, improve productivity and provide a safer environment for the operator. In fine-shape machining, typical signs of tool problems such as vibration, noise, chip flow characteristics and visual signs are almost unnoticeable without the use of special equipment. These characteristics increase the importance of automatic monitoring in fine-shape machining, however, sensing and interpretation of signals ar more complex. In addition, the shafts of the mini-tools break before the typical extensive cutting edge of the tool gets damaged. In this study, the existence of a relationship between the characteristics of the cutting force and tool usage was investigated, and tool breakage detection algorithm by LabVIEW was developed and the following results are obtained. It was possible to use a relative error compare which mainly used in established experiment and investigated tool breakage detection algorithm in time domain which can detect AE and cutting force signals more effective and accurate.

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Influence of Heel Insole and Visual Control on Body Sway Index with High-heeled Shoes (뒤꿈치 인솔착용과 시각통제 유무가 하이힐 착용 시 균형관련 지수에 미치는 영향)

  • Yoon, Jung-Gyu
    • Journal of the Korean Society of Physical Medicine
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    • v.9 no.4
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    • pp.407-413
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    • 2014
  • PURPOSE: We investigated the influence of heel insole and visual control on body sway index with high-heeled shoes. METHODS: The subjects of this study were 61 healthy students. None of the participants had any orthopedic or neurologic alterations. C90 area, C90 angle, trace length, sway average velocity were measured using a force plate by BT4. The variables were measured both with insole and without insole when wearing high-heeled shoes under the conditions of eyes open and eyes closed. The collected data were analyzed using the Kolmogorov-Smirnov test and paired t-test. RESULTS: When wearing high-heeled shoes with insole under the conditions of eyes open, trace length, C90 area, velocity were significantly more decreased than without insole (p<.01). When wearing high-heeled shoes with insole under the conditions of eyes closed, only C90 area was significantly more decreased than without insole (p<.05). When wearing high-heeled shoes with insole under the conditions of eyes open, trace length, C90 area, velocity were significantly more decreased than under the conditions of eyes closed (p<.01). CONCLUSION: The present study demonstrates that the use of high-heeled shoes with insole supported from heel to midfoot more increased static balance than without insole under the conditions of eyes open.