Development of a Driving Simulator with Analyzing Driver’s Characteristics Based on a Virtual Reality Head Mounted Display

Driving a vehicle is one of the most common daily yet hazardous tasks. One of the great interests in recent research is to characterize a driver’s behaviors through the use of a driving simulation. Virtual reality technology is now a promising alternative to the conventional driving simulations since it provides a more simple, secure and user-friendly environment for data collection. The driving simulator was used to assist novice drivers in learning how to drive in a very calm environment since the driving is not taking place on an actual road. This paper provides new insights regarding a driver’s behavior, techniques and adaptability within a driving simulation using virtual reality technology. The theoretical framework of this driving simulation has been designed using the Unity3D game engine (5.4.0f3 version) and programmed by the C# programming language. To make the driving simulation environment more realistic, the HTC Vive Virtual reality headset, powered by Steamvr, was used. 10 volunteers ranging from ages 19 - 37 participated in the virtual reality driving experiment. Matlab R2016b was used to analyze the data obtained from experiment. This research results are crucial for training drivers and obtaining insight on a driver’s behavior and characteristics. We have gathered diverse results for 10 drivers with different characteristics to be discussed in this study. Driving simulations are not easy to use for some users due to motion sickness, difficulties in adopting to a virtual environment. Furthermore, results of this study clearly show the performance of drivers is closely associated with individual’s behavior and adaptability to the driving simulator. Based on our findings, it can be said that with a VR-HMD (Virtual Reality-Head Mounted Display) Driving Simulator enables us to evaluate a driver’s “performance error”, “recognition errors” and “decision error”. All of which will allow researchers and further studies to potentially establish a method to increase driver safety or alleviate “driving errors”.

Experiment Research on Binocular Perceptual Characteristics around Peripheral Vision for Development of Head Mounted Display with Wide View

The head mounted display （HMD） is widely used in virtual reality technology. In common HMD, however, the binocular disparity is set to an equal fixed value in the entire range of view. Such HMD systems have several shortcomings when used for wide views. In this study, in order to realize a natural stereo sensation of HMD with wide view, we measure the characteristics of binocular stereo perception and binocular light perception. Results show that both the stereoacuity and light sensitivity decrease as the retina＇s eccentricity increases from fovea to periphery. However, the decrease of the stereoacuity is more rapid than that of the light sensitivity. These results suggest that the binocular disparity at the peripheral field should be small, otherwise double images would be observed instead of a stereo view. Based on the results we develop a relative binocular stereoacuity model which can be applied for the design of HMD systems with wide view.

VEGO:A novel design towards customizable and adjustable head-mounted display for VR

Background Virtual Reality(VR)technologies have advanced fast and have been applied to a wide spectrum of sectors in the past few years.VR can provide an immersive experience to users by generating virtual images and displaying the virtual images to the user with a head-mounted display(HMD)which is a primary component of VR.Normally,an HMD contains a list of hardware components,e.g.,housing pack,micro LCD display,microcontroller,optical lens,etc.Settings of VR HMD to accommodate the user's inter-pupil distance(IPD)and the user's eye focus power are important for the user's experience with VR.Methods Although various methods have been developed towards IPD and focus adjustments for VR HMD,the increased cost and complexity impede the possibility for users who wish to assemble their own VR HMD for various purposes,e.g.,DIY teaching,etc.In our paper,we present a novel design towards building a customizable and adjustable HMD for VR in a cost-effective manner.Modular design methodology is adopted,and the VR HMD can be easily printed with 3D printers.The design also features adjustable IPD and variable distance between the optical lens and the display.It can help to mitigate the vergence and accommodation conflict issue.Results A prototype of the customizable and adjustable VR HMD has been successfully built up with off-the-shelf components.A VR software program running on Raspberry Pi board has been developed and can be utilized to show the VR effects.A user study with 20 participants is conducted with positive feedback on our novel design.Conclusions Modular design can be successfully applied for building up VR HMD with 3D printing.It helps to promote the wide application of VR at affordable costs while featuring flexibility and adjustability.

Light field head-mounted display with correct focus cue using micro structure array

A new type of light fiehl display is proposed using a head-mounted display （HMD） and a micro structure array （MSA, lens array or pinhole array）. Each rendering point emits abundant rays from different directions into the viewer＇s pupil, and at one time the dense light field is generated inside the exit pupil of the HMD through the eyepiece. Therefore, the proposed method not only solves the problem of accommodation and convergence conflict in a traditional HMD, but also drastically reduces the huge data in real three-dimensional （3D） display. To demonstrate the proposed method, a prototype is developed, which is capable of giving the observer a real perception of depth.

VLSI design of 3D display processing chip for binocular stereo displays

In order to develop the core chip supporting binocular stereo displays for head mounted display （HMD） and glasses-TV, a very large scale integrated （VISI） design scheme is proposed by using a pipeline architecture for 3D display processing chip （HMD100）. Some key techniques including stereo display processing and high precision video scaling based bicubic interpolation, and their hardware implementations which improve the image quality are presented. The proposed HMD100 chip is verified by the field-programmable gate array （FPGA）. As one of innovative and high integration SoC chips, HMD100 is designed by a digital and analog mixed circuit. It can support binocular stereo display, has better scaling effect and integration. Hence it is applicable in virtual reality （VR）, 3D games and other microdisplay domains.

Image-Based Methods for Interaction with Head-Worn Worker-Assistance Systems

In this paper, a mobile assistance-system is described which supports users in performing manual working tasks in the context of assembling complex products. The assistance system contains a head-worn display for the visualization of information relevant for the workflow as well as a video camera to acquire the scene. This paper is focused on the interaction of the user with this system and describes work in progress and initial results from an industrial application scenario. We present image-based methods for robust recognition of static and dynamic hand gestures in realtime. These methods are used for an intuitive interaction with the assistance-system. The segmentation of the hand based on color information builds the basis of feature extraction for static and dynamic gestures. For the static gestures, the activation of particular sensitive regions in the camera image by the user’s hand is used for interaction. An HMM classifier is used to extract dynamic gestures depending on motion parameters determined based on the optical flow in the camera image.

超大视场头盔显示光学系统设计

设计了大视场头盔显示器的目视光学系统,用于满足头盔显示器对大视场、小畸变、高分辨率以及轻量化的苛刻要求。采用4×3阵列式排列、视场角为33°×24°的12组高质量成像目镜系统拼接成单眼目视光学系统来实现系统的大视场设计。为了使系统轻量化,每个单元目镜只采用一片透镜;透镜一面采用二元光学衍射面,利用其特殊色散特性校正目镜系统色差;另一面采用非球面,用于校正目镜光学系统的初、高级单色像差。其图像源为高亮度、高分辨率的OLED微显示器。设计结果显示:单目目视光学系统水平视场达到120°,垂直视场为60°,角分辨率为43pixel/(°);单个目镜系统传递函数在40lp/mm处,轴上视场高于0.62,全视场高于0.1;系统畸变小于3%;系统的双目视场为160°×60°,双目重叠视场为80°×60°。该设计实现了超大视场,满足头盔显示光学系统的成像要求。

基于增强现实技术的圆明园现场数字重建

增强现实(AR)技术是在虚拟现实技术的基础上发展起来的新兴研究领域,是一种利用计算机产生的附加信息对真实世界的景象增强的技术。AR系统的用户可以在看到真实环境的同时看到计算机产生的与之融合的文字、图片或虚拟物体的三维模型。阐述了AR 系统的基本组成和关键技术,介绍了用于圆明园现场数字重建的3种增强现实系统,即定点观察式、手持个人数据助理(PDA)式和基于头盔显示器(HMD)的可穿戴式增强现实系统。阐述了各系统的结构和原理,详细说明了定点观察式系统的研制现状及初步实验结果。

折/衍混合自由曲面式头戴显示器光学系统设计

为解决传统头戴式显示器大视场、大出瞳距与小型、轻量化之间的矛盾,设计了折/衍混合自由曲面式头戴显示器的光学系统。利用衍射元件的特殊色散特性校正系统色差;选取最佳的自由曲面面型组合校正系统的像散、彗差和畸变;由光学塑料(PMMA)注塑成型的自由曲面棱镜形成离轴结构,使光学系统结构紧凑、便于装调。设计得到的光学系统出瞳距离为17.4 mm,出瞳直径为4 mm,对角线视场为55°,光学系统的点斑RMS半径小于30μm,各视场光学调制传递函数在30 lp/mm时大于0.1,系统畸变小于10%。实际分析结果表明,该系统具有良好的成像质量,系统像差特性满足目镜系统的成像要求,可以满足虚拟现实各领域的实际需求。

双自由曲面大视场头盔显示光学系统设计

视场大小是评价头盔显示器在虚拟现实等领域的关键性能指标,为了克服视场增加带来各类像差急剧增大的困难,提出了一种基于双自由曲面的大视场头盔显示光学系统。首先,分析了双椭球结构实现大视场与低畸变的基本原理,指出了其难以校正除畸变以外其他像差的原因。接着,提出根据系统对称性和光路走向采用竖直方向对称、水平方向不对称的自由曲面反射镜校正离轴像差,完成了基于双自由曲面反射镜的大视场头盔显示光学系统设计。系统视场范围为106.3°（H）×80°（V）,最大相对畸变为6.97%,出瞳直径8 mm,点眼距19 mm。单目系统向外倾斜8°时,双目视场范围为122.3°（H）×80°（V）,双目重叠视场为90.3°（H）×80°（V）,瞳距在55~71 mm范围内可调节。对系统性能分析结果表明：相比双椭球结构,系统成像质量得到较大提高;视场范围和相对畸变满足虚拟现实领域的应用要求。

离轴回转对称棱镜式头戴显示器目镜的研制

针对大曲率自由曲面棱镜在加工中存在表面粗糙度差的问题,本文采用离轴非球面面型研制了棱镜式虚拟显示目镜。目镜的3个光学表面都采用了回转对称的非球面面型,其加工精度比自由曲面高且加工难度大大降低。通过控制棱镜各表面的曲率、倾斜角度来实现短焦距和大视场并通过优化高次非球面系数校正像差。实验结果显示:研制的目镜其光瞳大小为6mm,视场大小为55°;在30lp/mm处,轴上视场的调制传递函数(MTF)值高于0.2,轴外视场的MTF值高于0.1,目镜的最大畸变量为-5.37%。棱镜的检测和试验结果表明:与自由曲面棱镜相比,采用非球面面型能够显著降低棱镜表面的粗糙度,避免图像重影现象,成像更为清晰,虚拟成像的目视效果得到了明显改善。

头盔显示系统评述

介绍了当今军用航空头盔显示系统的特点和现状、能达到的精度和适用范围。阐述了头盔显示系统涉及的主要生物动力学特性——重量、重心和极限碰撞条件,并对头盔显示系统主要技术问题——头盔、跟踪器和显示器阐明了发展前景,指出全息光学波导技术会对头盔显示器的发展产生重大影响。

现代空战中的头盔显示器及其关键技术

首先概述了头盔显示器的基本概念、结构、组成和分类 ,头盔显示器的主要任务、工作过程以及研制现状和典型产品 ,之后根据现代空战的特点分析了头盔显示器在现代空战中主要作用 。

一种三维头盔显示器驱动电路设计方案

针对三维头盔显示器的结构与特点,提出了以PC为平台,以FPGA(现场可编程门阵列)为控制核心,以OLED(有机发光二极管)微显示芯片为图像源的三维头盔显示器USB2.0接口电路设计方案;并且在PC机上利用三维造型软件3ds MAX进行三维建模并从中提取出具有一定视差的双目图像,然后通过USB2.0接口将其按照给定的视频格式并行传送到左右两个微显示芯片进行显示,从而实现了双目立体视觉,验证了方案的可行性.

基于惯性与光学技术的头位测量方法设计

针对现代战争对头盔快速姿态定位的要求,基于惯性定位和光学定位原理,设计了一种基于MEMS/CCD的头位姿态测量新方法。在头盔上加装一套MEMS惯导系统,通过与CCD的组合,实现对头盔姿态的实时测量。阐述了测量原理,建立了数学模型,设立了初始装订办法,并进行了仿真验证。仿真结果表明,该方法可以获得良好的快速性和测量精度,在不到5s的时间里就完成了对头位姿态失准角的估计,估计精度达2′,可有效完成对头盔姿态的测量,实现实时头位跟踪。

头盔显示器及其关键技术

简要概述了头盔显示器的基本概念、主要任务、工作过程以及研制现状和典型产品 ,根据现代空战的特点分析了头盔显示器在现代空战中的主要作用 。

一种实用的头盔显示器立体图像生成技术

提出了一种实用的立体图像生成技术,首先阐述了立体视觉的基本原理,指出生成立体图像的基本要素.然后说明了虚拟场景的单眼视图一种实现方法,以及与之对应的双眼立体视图的设计原理和实现方法,同时设计了适合于分时显示和同时显示设备的渲染框架.本文还对立体视图的视频信号的物理输出提出了适当的方法,使其适用于头盔显示器.

虚拟座舱观景系统的技术研究

虚拟座舱是虚拟现实技术的一种实际应用，本文论述了虚拟座舱视景系统的构成及有关的几个技术。包括用于双目成像显示算法的双中心投影法，给出了一种较为通用的头盔立体显示计算模型和一种实用的时钟同步算法。提出了利用头部运动预测法（DR算法）对系统延时进行补偿，所设计的虚拟座舱的视景显示包括座舱的内外视景、仪表和HUD平显火控显示部分，所有这些视景生成的工作，都在WindowsNT平台上利用OpenGL编程的方法实现的。

基于微惯性器件的头部运动综合测量方法研究

针对运动平台上头部姿态测量问题,提出一种可以获得更快测量速度、更高测量精度的综合测量方法。通过卡尔曼滤波将分别由视觉测量和微惯性测量得到的头部姿态数据进行数据融合。利用视觉测量对微惯性测量进行校正,综合了视觉测量方法误差不随时间变化与微惯性测量方法测量速度快、测量范围大的优点,抑制了惯性测量随时间累积产生的无约束发散误差,克服了视觉测量方法范围受限、容易受到干扰的缺点,并经过试验分析与仿真,得到了验证。

基于MARG传感器的头部姿态解算方法研究

针对头盔显示器(HMD)的头部姿态检测系统中单一传感器进行头部姿态解算准确度低、精度粗略的问题,提出了一种基于MARG传感器的头部姿态解算方法。将互补滤波与PI算法相结合估算陀螺仪的漂移误差,再通过扩展卡尔曼滤波(EKF)实现姿态数据融合。设计了由CC1310、陀螺仪、加速度计和磁强计组成的头部姿态检测单元进行测试实验。与单独的EKF对比,结果表明,这种算法对陀螺仪自身的漂移和加速度计噪声有抑制作用,提高了头部姿态解算的精度和稳定性。