헤드마운티드 디스플레이를 활용한 전방위 카메라 기반 영상 렌더링 동기화 시스템

이승준(Seungjoon Lee),강석주(Suk-Ju Kang) 대한전기학회 2018 전기학회논문지 Vol.67 No.6

This paper proposes a novel method for the omnidirectional camera-based image rendering synchronization system using head mounted display. There are two main processes in the proposed system. The first one is rendering 360-degree images which are remotely photographed to head mounted display. This method is based on transmission control protocol/internet protocol(TCP/IP), and the sequential images are rapidly captured and transmitted to the server using TCP/IP protocol with the byte array data format. Then, the server collects the byte array data, and make them into images. Finally, the observer can see them while wearing head mounted display. The second process is displaying the specific region by detecting the user"s head rotation. After extracting the user"s head Euler angles from head mounted display"s inertial measurement units sensor, the proposed system display the region based on these angles. In the experimental results, rendering the original image at the same resolution in a given network environment causes loss of frame rate, and rendering at the same frame rate results in loss of resolution. Therefore, it is necessary to select optimal parameters considering environmental requirements.

정밀모형안을 이용한 Head Mounted Display용 렌즈계 설계

박성찬,안현경 한국광학회 2003 한국광학회지 Vol.14 No.3

본 논문에서는 구면수차와 Stiles-Crowford 효과를 고려하여 인간의 눈을 모델링한 정밀모형안과 등가인 렌즈모듈 모형안의 설계에 관하여 논의하였고, 렌즈모듈 모형안을 적용한 Head Mounted Display(HMD)용 광학계를 설계 및 평가하였다. HMD용 광학계에서 요구되는 소형화, 고성능 및 고해상도 등의 필수조건들을 만족시키기 위해 회절광학소자와 비구면을 이용하여 색수차와 단색수차를 보정하였다. SVGA급 480,000화소를 갖는 0.47 인치 micro-display, 플라스틱 hybrid 렌즈, 그리고 렌즈모듈 모형안으로 HMD용 광학계를 구성하였다. 설계된 광학계의 초점거리는 31.25 mm, FOV는 24H$\times$18V$\times$30D degrees, 그리고 전장길이는 59.1 mm이다. 결과적으로, 사용자가 편안함을 느낄 수 있는 HMD에 유용한 광학계를 얻었다. We discussed the design of lens module schematic eyes equivalent to finite model eyes, which are used to model the human eye based on spherical aberration and Stiles-Crowford effect. The optical system for head mounted display (HMD) is designed and evaluated using lens module schematic eyes. In addition to a compact HMD system, an optical system with high Performance is required. To satisfy these requirements, we used diffractive optical elements and aspheric surfaces so that the color and mono-chromatic aberrations were corrected. The optical system for HMD is composed of 0.47 inch micro-display of SVGA grade with 480,000 pixels, a plastic hybrid lens for the virtual image, and the lens module schematic eyes. The designed optical system fulfills the current specifications of HMD: such as, EFL of 31.25 mm, FOV of 24H$\times$18V$\times$30D degrees, and overall length of 59.1 mm. As a result, we could design an optical system useful for HMD; the system is expected to be comfortable while the user wears it.

Development of the Flexible Observation System for a Virtual Reality Excavator Using the Head Tracking System

Quang Hoan Le,Jong-Il Bae,Young-Man Jeong,Chi Thanh Nguyen,Soon-Yong Yang 제어로봇시스템학회 2015 제어로봇시스템학회 국제학술대회 논문집 Vol.2015 No.10

Operating excavator on the risk surroundings is not safe for human to control on site. Consequently, automatic excavator called Field Robot has been researched to protect the workers from the hazardous environments. The remote excavation system is required to perform in such environments. This paper presents the study on remote control system for the Field Robot and augmented reality vision for user using head tracker system. The design of the remote control system that consist Remote Station and Filed Robot. In Remote Station, user can send the control commands through wireless communication. Besides, the Inertial Measurement Unit (IMU) sensor is integrated in a head mounted display (HMD) to track the motion of human’s head. These signals are transferred to the pan/tilt motor controller and to operate the motion of the CCD camera following the movement of operator’s head. The Field Robot is also contributed and some experiments are carried out to prove the feasibility of the proposed system.

헤드 마운티드 디스플레이(HMD) 기반 가상현실 디자인 사례 연구: 시지각 특성에 따른 사용자 경험을 중심으로

정새해,김지연,김형신 한국기초조형학회 2019 기초조형학연구 Vol.20 No.3

The purpose of this paper is to present a VR draft design solution that enables designers and developers to easily communicate with each other in the production process of interactive virtual reality(VR) works and to reveal the necessity of VR design methodology and tools. The background and starting point of this study were the inefficiency of the VR production process due to the miscommunication on the two-dimensional(2D) image based VR draft between designers and developers. We propose that the head-mounted display(HMD)’s distorted field of view and VR HMD specific user experience cause different interpretation on VR draft. To address this issues, first, we analyze the visual cognition of general HMD, and then analyze two cases of VR work-<Toy Clash> VR game and <Toegye’s Ten Diagrams on Sage Learning> VR work- that have suffered from the problem of size and position visibility through HMD. Based on the case analysis, a user test was conducted to experiment with the experience of user's HMD visual cognition on objects’ size and position in the virtual environment. The experiment shows that the user’s cognition of the objects’ distance and size on HMD was very inaccurate. Therefore, we conclude that the user’s inaccurate field of vision by HMD influences the design and the development process of VR production. Furthermore, an HMD-friendly VR draft design methodology and a design software are needed for both designers and developers so that they can easily communicate by the VR draft and simulate an accurate HMD’s field of view. We believe that a better VR draft will improve the efficiency of the VR production process. 본 논문은 가상현실(VR) 콘텐츠 제작에서 디자인과 개발 분야가 서로 용이하게 의사소통할 수 있는 VR 시안솔루션을 제시하고 VR 시안의 디자인 방법론과 툴의 필요성을 밝히는 것에 목적이 있다. 연구의 배경이자 시발점은 평면 이미지(2D) 형식의 VR 제작 시안을 각각 다르게 해석함에 따라 발생하는 디자이너와 개발자 간 의사소통의 어려움과 이로 인한 제작 과정의 비효율성에 있었다. 우리는 이러한 문제의 발생 원인을 VR 사용 디바이스인 헤드 마운티드 디스플레이(HMD) 사용자 시야의 특수성과 이 점이 반영되지 않은 VR 시안에 있다고보았다. 이를 밝히고자 우선 HMD 사용자 시야의 특징들을 분석하였고 이어서 HMD 사용자 시야의 특수성에서비롯되는 문제를 겪었던 <토이 클래시> VR 게임과 <퇴계 성학십도> VR 작업의 제작 사례를 분석하였다. 두 가지 사례를 통해 HMD 상에서 발생하는 사용자 시야의 왜곡이 VR 작업의 제작 과정과 결과물에 문제를 일으킬수 있다는 사실을 발견하였다. 우리는 VR 상에서 사용자가 대상의 크기와 위치를 어느 정도 구분하는지 구체적으로 알아보기 위해 HMD 사용자 실험을 진행하였다. 실험 결과, 사용자가 HMD상에서 크기와 위치 정보가 각각 다른 두 오브젝트의 차이를 구분하지 못한다는 점을 확인하였다. 따라서 HMD 사용자 경험에서의 부정확한시지각 현상이 VR 작업 제작의 디자인 및 개발 프로세스에 영향을 준다는 결론을 도출할 수 있었다. 그리고 이러한 HMD 사용자 경험을 감안한 VR 시안 디자인 방법론과 디자인 툴이 필요하다는 결론에 도달하였다. 본 연구가 디자인과 개발 분야의 효율적인 VR 작업 프로세스를 위한 VR 디자인 방법론을 제안하며 나아가 HMD와VR 개발 엔진의 기술개발에 유익한 방향을 제시할 수 있기를 바란다.

Head Mounted Display와 트레드밀을 사용한 실감형 가상현실 학습환경이 사용자의 사이버멀미에 미치는 영향

류지헌 ( Ryu Jeeheon ),유승범 ( Yu Seungbeom ) 안암교육학회 2016 한국교육학연구 Vol.22 No.3

이 연구는 HMD와 보행이 가능한 내비게이션을 조합한 실감형 가상현실 체제에서 사용자가 지각하는 사이버멀미와 사용자 경험을 분석한 것이다. HMD는 입체지각이 가능할 뿐만 아니라 사용자의 몰입감을 높일 수 있기 때문에 가상실재감을 형성하는데 중요한 역할을 한다. 그러나 사이버멀미를 유발하는 부정적인 요인을 갖고 있다. 트레드밀을 사용한 실감형 가상현실에서는 사용자가 직접적인 보행을 할 수 있다는 점에서 환경과의 상호작용을 높일 수있다는 장점을 갖고 있다. 19명의 대학생이 연구에 참여했으며, 사용자의 사이버멀미를 측정하기 위해서 시뮬레이터 멀미 측정도구(simulator sickness questionnaire: SSQ)를 적용했다 (메스꺼움, 안구운동불안, 방향감각 상실, 총점의 네 요인으로 구성). 또한 실험참가자 중에서 6명을 대상으로 심층면담을 실시했다. 연구결과에 따르면 내비게이션 방법은 유의미한 영향을 미치지 않았으나, HMD를 사용하면 사이버멀미가 나타났다. 또한 사이버멀미의 요인과 HMD 사이에는 유의미한 상호작용이 있는 것으로 나타났다. HMD를 사용하는 것이 사용자에게 실감형 경험을 제공하는데 가장 효과적이라는 결론을 내릴 수 있었다. 그러나 착용감등에 의한 부정적인 요인이 발생한다는 점을 확인할 수 있었다. 보행기반의 내비게이션이 성공적이기 위해서는 적절한 반응속도, 자연스러운 보행자세, 화면에 제시되는 화면자극과의 공조가 중요하다는 점을 알 수 있었다. 비록 HMD가 가상현실의 몰입감을 높이는데 효과적 이지만 교육에 맞도록 적용하는 것은 쉽지 않을 수 있다. The purpose of this study was to explore user experience in a virtual reality based environment with head mounted display (HMD) and treadmill based gait navigation. HMD has been regarded as a key display for users to provide depth perception as well as to increase immersive experience. However, HMD is also known to cause a cyber sickness. Treadmill can provide embodied interaction to simulate gait pattern by emulating walking to navigate virtual reality environment. In order to measure the cyber sickness Simulator Sickness Questionnaire (SSQ) was applied to 19 college students. Among the participants six participants were selected for an in-depth interview to analyze how the cyber sickness was formed in experiencing the immersive virtual reality. In general HMD can create immersive perception for facilitating real-like experience as if users are involved in a certain situation. However, HMD was not comfortable for various reasons.

Development of the Flexible Observation System for a Virtual Reality Excavator Using the Head Tracking System

Q. H. Le(레광환),Y. M. Jeong(정영만),C. T. Nguyen(웬치탄),S. Y. Yang(양순용) 유공압건설기계학회 2015 드라이브·컨트롤 Vol.12 No.2

Excavators are versatile earthmoving equipment that are used in civil engineering, hydraulic engineering, grading and landscaping, pipeline construction and mining. Effective operator training is essential to ensure safe and efficient operating of the machine. The virtual reality excavator based on simulation using conventional large size monitors is limited by the inability to provide a realistic real world training experience. We proposed a flexible observation method with a head tracking system to improve user feeling and sensation when operating a virtual reality excavator. First, an excavation simulator is designed by combining an excavator SimMechanics model and the virtual world. Second, a head mounted display (HMD) device is presented to replace the cumbersome large screens. Moreover, an Inertial Measurement Unit (IMU) sensor is mounted to the HMD for tracking the movement of the operator"s head. These signals consequently change the virtual viewpoint of the virtual reality excavator. Simulation results were used to analyze the performance of the proposed system.

Development of the head tracking system for a virtual reality excavator

Soon-Yong Yang,Quang Hoan Le,Jong-Il Bae,Young-Man Jeong,Chi Thanh Nguyen,Ji-Woo Oh,Tae-Un Kim 유공압건설기계학회 2015 유공압건설기계학회 학술대회논문집 Vol.2015 No.10

Operating excavator on the risk surroundings is not safe for human to control on site. Consequently, automatic excavator called Field Robot has been researched to protect the workers from the hazardous environments. The remote excavation system is required to perform in such environments. This paper presents the study on remote control system for the Field Robot and augmented reality vision for user using head tracker system. The design of the remote control system that consist Remote Station and Filed Robot. In Remote Station, user can send the control commands through wireless communication. Besides, the Inertial Measurement Unit (IMU) sensor is integrated in a head mounted display (HMD) to track the motion of human’s head. These signals are transferred to the pan/tilt motor controller and to operate the motion of the CCD camera following the movement of operator’s head. The Field Robot is also contributed and some experiments are carried out to prove the feasibility of the proposed system.

Development of the Flexible Observation System for a Virtual Reality Excavator Using the Head Tracking System

레광환,정영만,웨치탄,양순용 사단법인 유공압건설기계학회 2015 드라이브·컨트롤 Vol.12 No.2

Excavators are versatile earthmoving equipment that are used in civil engineering, hydraulic engineering, grading and landscaping, pipeline construction and mining. Effective operator training is essential to ensure safe and efficient operating of the machine. The virtual reality excavator based on simulation using conventional large size monitors is limited by the inability to provide a realistic real world training experience. We proposed a flexible observation method with a head tracking system to improve user feeling and sensation when operating a virtual reality excavator. First, an excavation simulator is designed by combining an excavator SimMechanics model and the virtual world. Second, a head mounted display (HMD) device is presented to replace the cumbersome large screens. Moreover, an Inertial Measurement Unit (IMU) sensor is mounted to the HMD for tracking the movement of the operator's head. These signals consequently change the virtual viewpoint of the virtual reality excavator. Simulation results were used to analyze the performance of the proposed system.

헤드마운트 디스플레이 응용을 위한 고효율 협시야각 LCD 최적화 연구

위성희,강민진,황의선,백기현,김진환,박현욱,정병호 한국광학회 2022 한국광학회지 Vol.33 No.2

In a head-mounted display (HMD) for virtual-reality applications, a narrow viewing angle is preferred to the usual, wide viewing angle becausethe HMD is positioned close in front of the user's eyes, and the display position is fixed. In this paper, we propose a new back-light unit (BLU) forimplementing a narrow viewing angle, which is suitable for a HMD. By optimizing the scattering patterns in the light-guide-plate and inverse-prism structures, the viewing angle and correlations between structural parameters in the BLU components are analyzed with ray-tracing simulations. As a result, a double-angle inverse-prism structure incorporating the scattering patterns of a light-guide plate is chosen, which results in a 14% increase incenter luminance, a 16% decrease in the vertical viewing angle, and a light efficiency of up to 70%, compared to a conventional BLU. Thus, the new BLU system is expected to be applied in a high-efficiency liquid crystal display.

Beyond Head-mounted Display: Extended Field of View using Sparse Peripheral Display Techniques

Jiwoong Heo(허지웅),Kwanguk Kim(김광욱) Korean Institute of Information Scientists and Eng 2019 정보과학회논문지 Vol.46 No.8

The field of view (FoV) is one of the main properties of virtual reality (VR) systems with head-mounted displays (HMDs). While preceding VR studies have suggested novel methodologies to extend the FoV of HMDs, there were limitations in those methods, including: heavy weight, high cost, and screen distortion. The observation through the human retina indicated that the density of human photoreceptors are distributed variedly between the central and peripheral visual fields. The sparse peripheral display (SPD) was proposed based on these observations. In this study, we suggest and compare the combination of SPD technologies using different number (2-80) of light-emitting diodes (LEDs) and different tasks (visual search and emotion tasks). The results showed that the visual-search task with use of six LEDs and there were no significant differences in the emotion task. Discussion of the potential applications of SPD-HMD systems, including therapeutic techniques to assist handicapped people was done.