scholarly journals Colocation for SLAM-Tracked VR Headsets with Hand Tracking

Computers ◽  
2021 ◽  
Vol 10 (5) ◽  
pp. 58
Author(s):  
Dennis Reimer ◽  
Iana Podkosova ◽  
Daniel Scherzer ◽  
Hannes Kaufmann
Keyword(s):  
Virtual Reality ◽  
Fixed Point ◽  
Virtual Environment ◽  
Tracking System ◽  
Calibration Method ◽  
Hand Tracking ◽  
Experimental Procedure ◽  
The Third ◽  
Calibration Methods ◽  
Head Mounted Displays

In colocated multi-user Virtual Reality applications, relative user positions in the virtual environment need to match their relative positions in the physical tracking space. A mismatch between virtual and real relative user positions might lead to harmful events such as physical user collisions. This paper examines three calibration methods that enable colocated Virtual Reality scenarios for SLAM-tracked head-mounted displays without the need for an external tracking system. Two of these methods—fixed-point calibration and marked-based calibration—have been described in previous research; the third method that uses hand tracking capabilities of head-mounted displays is novel. We evaluated the accuracy of these three methods in an experimental procedure with two colocated Oculus Quest devices. The results of the evaluation show that our novel hand tracking-based calibration method provides better accuracy and consistency while at the same time being easy to execute. The paper further discusses the potential of all evaluated calibration methods.

Methods to Calibrate Projection Transformation Parameters for See-Through Head-Mounted Displays

1996 ◽  
Vol 5 (1) ◽  
pp. 122-135 ◽  
Author(s):  
Takashi Oishi ◽  
Susumu Tachi
Keyword(s):  
Virtual Environment ◽  
Least Squares Method ◽  
Calibration Method ◽  
The Real ◽  
Virtual Objects ◽  
Real Environment ◽  
Calibration Methods ◽  
Head Mounted Displays ◽  
Transformation Parameters ◽  
Projection Transformation

See-through head-mounted displays (STHMDs), which superimpose the virtual environment generated by computer graphics (CG) on the real world, are expected to be able to vividly display various simulations and designs by using both the real environment and the virtual environment around us. However, we must ensure that the virtual environment is superimposed exactly on the real environment because both environments are visible. Disagreement in matching locations and size between real and virtual objects is likely to occur between the world coordinates of the real environment where the STHMD user actually exists and those of the virtual environment described as parameters of CG. This disagreement directly causes displacement of locations where virtual objects are superimposed. The STHMD must be calibrated so that the virtual environment is superimposed properly. Among the causes of such errors, we focus both on systematic errors of projection transformation parameters caused in manufacturing and differences between actual and supposed location of user's eye on STHMD when in use, and propose a calibration method to eliminate these effects. In the calibration method, the virtual cursor drawn in the virtual environment is directly fitted onto targets in the real environment. Based on the result of fitting, the least-squares method identifies values of the parameters that minimize differences between locations of the virtual cursor in the virtual environment and targets in the real environment. After we describe the calibration methods, we also report the result of this application to the STHMD that we have made. The result is accurate enough to prove the effectiveness of the calibration methods.

Virtual Reality (VR) in Pediatrics: Innovative Perspectives With Special Reference To Clinical Applications and Pediatric Rehabilitation

2021 ◽  
Author(s):  
Stefan Bittmann
Keyword(s):  
Virtual Reality ◽  
Virtual Environment ◽  
Virtual Worlds ◽  
Virtual World ◽  
Mixed Reality ◽  
Clinical Applications ◽  
Virtual Space ◽  
Data Glove ◽  
Input Devices ◽  
Head Mounted Displays

Virtual reality (VR) is the term used to describe representation and perception in a computer-generated, virtual environment. The term was coined by author Damien Broderick in his 1982 novel “The Judas Mandala". The term "Mixed Reality" describes the mixing of virtual reality with pure reality. The term "hyper-reality" is also used. Immersion plays a major role here. Immersion describes the embedding of the user in the virtual world. A virtual world is considered plausible if the interaction is logical in itself. This interactivity creates the illusion that what seems to be happening is actually happening. A common problem with VR is "motion sickness." To create a sense of immersion, special output devices are needed to display virtual worlds. Here, "head-mounted displays", CAVE and shutter glasses are mainly used. Input devices are needed for interaction: 3D mouse, data glove, flystick as well as the omnidirectional treadmill, with which walking in virtual space is controlled by real walking movements, play a role here.

scholarly journals Characterization of Visual Acuity and Contrast Sensitivity using Head-Mounted Displays in a Virtual Environment: A Pilot Study

2019 ◽  
Vol 63 (1) ◽  
pp. 547-551
Author(s):  
David Sproule ◽  
Rosemarie Figueroa Jacinto ◽  
Steve Rundell ◽  
Jacob Williams ◽  
Sam Perlmutter ◽  
...  
Keyword(s):  
Visual Acuity ◽  
Virtual Reality ◽  
Pilot Study ◽  
Contrast Sensitivity ◽  
Virtual Environment ◽  
Real World ◽  
Appropriate Use ◽  
Head Mounted Displays ◽  
Visualization Tools

Virtual reality (VR) and personal head-mounted displays (HMDs) can be a viable tool for the presentation of scientifically accurate and valid demonstrative data in the courtroom. However, the capabilities and limitations of the technology need to be fully characterized. The current pilot study evaluated visual acuity and contrast sensitivity using two commercially available HMDs (Oculus Rift and HTC Vive Pro). Preliminary findings indicated that visual acuity and contrast sensitivity experienced in VR may be less than what is experienced in real-world scenarios. The current pilot study provides a quantitative approach for characterizing the limitations of VR with respect to visual acuity and contrast sensitivity, and provides recommendations for the appropriate use of this technology when performing forensic investigations and developing visualization tools.

Accessibility Evaluation in Aircraft Cabin Based on Virtual Reality

2014 ◽  
Vol 651-653 ◽  
pp. 1511-1514 ◽  
Author(s):  
Xian Li ◽  
Hu Liu
Keyword(s):  
Virtual Reality ◽  
Virtual Environment ◽  
Evaluation System ◽  
Tracking System ◽  
Rapid Development ◽  
New Method ◽  
Air Transport ◽  
Aircraft Cabin ◽  
Air Transport Industry ◽  
Accessibility Evaluation

With the rapid development of the air transport industry, more attention is paid to interior ergonomics analysis which directly affects the time and cost spent during design. To provide a quick and human-in-loop accessibility way to evaluate accessibility in aircraft cabin, a new method based on virtual reality is proposed. In this method, the digital mock-up model is converted to other format which is need to build a virtual environment first, then virtual environment is built and a virtual hand is driven through tracking hand’s position by A.R.T(Advanced Realtime Tracking ) system to carry on accessibility evaluation in the virtual environment. Based on above-mentioned method the aircraft cabin accessibility evaluation system is designed and realized, which is verified by one case of a certain aircraft cabin. The result shows this method is simple and useful, offering a new way for accessibility evaluation in aircraft cabin.

scholarly journals Development and Calibration of an Eye-Tracking Fixation Identification Algorithm for Immersive Virtual Reality

Sensors ◽  
2020 ◽  
Vol 20 (17) ◽  
pp. 4956
Author(s):  
Jose Llanes-Jurado ◽  
Javier Marín-Morales ◽  
Jaime Guixeres ◽  
Mariano Alcañiz
Keyword(s):  
Virtual Reality ◽  
Eye Tracking ◽  
Tracking System ◽  
Time Windows ◽  
Relevant Information ◽  
Identification Algorithm ◽  
Immersive Virtual Reality ◽  
Head Mounted Display ◽  
Gaze Patterns ◽  
Head Mounted Displays

Fixation identification is an essential task in the extraction of relevant information from gaze patterns; various algorithms are used in the identification process. However, the thresholds used in the algorithms greatly affect their sensitivity. Moreover, the application of these algorithm to eye-tracking technologies integrated into head-mounted displays, where the subject’s head position is unrestricted, is still an open issue. Therefore, the adaptation of eye-tracking algorithms and their thresholds to immersive virtual reality frameworks needs to be validated. This study presents the development of a dispersion-threshold identification algorithm applied to data obtained from an eye-tracking system integrated into a head-mounted display. Rules-based criteria are proposed to calibrate the thresholds of the algorithm through different features, such as number of fixations and the percentage of points which belong to a fixation. The results show that distance-dispersion thresholds between 1–1.6° and time windows between 0.25–0.4 s are the acceptable range parameters, with 1° and 0.25 s being the optimum. The work presents a calibrated algorithm to be applied in future experiments with eye-tracking integrated into head-mounted displays and guidelines for calibrating fixation identification algorithms

Error Measurement and Calibration in Developing Virtual-Reality-Assisted Microassembly System

2015 ◽  
Vol 9 (6) ◽  
pp. 619-628 ◽  
Author(s):  
Ren-Jung Chang ◽  
◽  
Jia-Cheng Jau
Keyword(s):  
Virtual Reality ◽  
Virtual Environment ◽  
System Development ◽  
Calibration Method ◽  
Development Stage ◽  
Deviation Angle ◽  
Charge Coupled Device ◽  
Virtual System ◽  
Representative Points ◽  
Operational Error

The operational error of a virtual reality (VR) assisted vision-based microassembly system is measured and calibrated during the system development stage. The vision-based microassembly system was designed and its opto-mechanical model was established in a virtual environment. By measuring the errors between the representative points in the images of virtual cameras and charge-coupled device (CCD) visual systems, the errors in the virtual environment were compensated by correcting the projection matrix parameters, the view matrix parameters, the initial components position, and the deviation angle for the working stage motion. The effectiveness of the proposed VR-assisted fine calibration method was tested by performing VR calibration on the virtual system.

An Experimental Comparison of Three Methods for Collision Handling in Virtual Environments

1997 ◽  
Vol 41 (2) ◽  
pp. 1273-1277 ◽  
Author(s):  
Jeffrey Jacobson ◽  
Michael Lewis
Keyword(s):  
Virtual Reality ◽  
Virtual Environments ◽  
Virtual Environment ◽  
Experimental Comparison ◽  
The Third ◽  
Collision Handling ◽  
Seeking Behavior ◽  
Virtual Body

This study compares three common strategies for handling collisions between the user's virtual body and other objects in a cluttered virtual environment. Test subjects sought “treasures” in a maze of narrow corridors which were embedded in a jumble of irrelevant shapes. The application ran on a PC, with the mouse and screen as the interface. When encounters an object, he either passes through it, stops completely, or is deflected around it. Data show that the third strategy best facilitates goal-seeking behavior with this interface and for this type of problem. This result is significant because collision handling is critically important to the usefulness of Virtual Reality applications. Furthermore, the screen-and-mouse interface is both the most common and least studied for virtual environments.

Astronaut Training using Virtual Reality in a Neutrally Buoyant Environment

2017 ◽  
Vol 2 (2) ◽  
pp. 319 ◽  
Author(s):  
Timothy Everson ◽  
Christopher McDermott ◽  
Aaron Kain ◽  
Cesar Fernandez ◽  
Ben Horan
Keyword(s):  
Virtual Reality ◽  
Virtual Environment ◽  
Real Life ◽  
Physical Space ◽  
Tactile Feedback ◽  
The Body ◽  
Hand Tracking ◽  
Training Environment ◽  
Astronaut Training ◽  
Neutrally Buoyant

<div><p>Astronauts undergo significant training in preparation for operating in space. In the past governments have been driving space exploration through ventures such as the National Aeronautics and Space Administration (NASA), however more recently new private companies have formed such as SpaceX who are designing commercially viable and reusable spacecraft. As such, the economics of space travel are more important than ever, and there is a logical need to research affordable and effective training procedures for astronauts.</p><p>Virtual Reality (VR) has been shown to be an effective technique for training people to perform high skilled physical tasks such as medical surgery. Research into VR as a platform for training astronauts has shown encouraging results with the implementation of hand tracking data gloves allowing the trainee to interact with the virtual environment. Further, there is evidence that VR can aid in the treatment of phobias with exposure therapy by better preparing the patient for real life exposure. Tactile feedback was found to enhance the treatment. Hence training with VR may help prepare an astronaut for the experience of operating in space through exposure to realistic simulations.</p><p>This paper proposes using existing underwater systems with VR to create a low cost extra vehicular activity (EVA) astronaut training simulation. Incorporation of tactile feedback and methods to track the body, hands and finger flexure, enabling user interaction with the virtual environment was explored. This allows for the creation of a varied neutrally buoyant training environment with a smaller physical space requirement compared to existing methods.</p></div>

scholarly journals Hand Tracking for Immersive Virtual Reality: Opportunities and Challenges

2021 ◽  
Vol 2 ◽  
Author(s):  
Gavin Buckingham
Keyword(s):  
Virtual Reality ◽  
Best Practices ◽  
Hand Tracking ◽  
Immersive Virtual Reality ◽  
Software Developers ◽  
Widespread Adoption ◽  
Head Mounted Displays ◽  
Integral Feature

Hand tracking has become an integral feature of recent generations of immersive virtual reality head-mounted displays. With the widespread adoption of this feature, hardware engineers and software developers are faced with an exciting array of opportunities and a number of challenges, mostly in relation to the human user. In this article, I outline what I see as the main possibilities for hand tracking to add value to immersive virtual reality as well as some of the potential challenges in the context of the psychology and neuroscience of the human user. It is hoped that this paper serves as a roadmap for the development of best practices in the field for the development of subsequent generations of hand tracking and virtual reality technologies.

Sign in / Sign up

Export Citation Format

Share Document