Collaborative Augmented Reality System Research Articles

Collaborative Augmented Reality: A Proposed Technology Acceptance Model

A collaborative augmented reality (CAR) system allows multiple users to communicate with each other in a shared 3D environment. Technology Acceptance Model (TAM) is a well-known method for predicting user acceptance of new technology, it also has the two strongest dimensions of acceptance: perceived usefulness and perceived ease of use. However, it can be further developed with external dimensions to investigate acceptance more comprehensively for the CAR system, with its 3D characteristics and collaborative ability, requires additional dimensions for measurement. This study aims to analyze and identify a suitable external dimension to be incorporated in TAM for CAR. We acquired the previous using the Web of Science database, which included keywords such as 'augmented reality,' 'virtual reality,' and 'technology acceptance model.' We analyzed eighteen high quality papers from a pool of ninety-seven papers, including journals and conferences. Resultantly, thirty-two external dimensions have been identified from previous TAM studies. After thorough analysis, a foundation TAM for the CAR system is proposed, along with suggestions for external dimensions for different CAR domain applications. The developed TAM includes perceived enjoyment, aesthetic quality, system quality, social presence, satisfaction, information quality, interactivity, collaboration quality and embodiment quality in the CAR context. Other factors, such as social norms, mobility, and others, are applicable to different CAR domain applications. The identified acceptance factors will assist researchers in enhancing their collaborative experience and conducting further analysis in the field of CAR.

Technology acceptance of a wearable collaborative augmented reality system in learning chemistry among junior high school students

Technology acceptance of a wearable collaborative augmented reality system in learning chemistry among junior high school students

A Multi-User Collaborative AR System for Industrial Applications.

Augmented reality (AR) applications are increasingly being used in various fields (e.g., design, maintenance, assembly, repair, training, etc.), as AR techniques help improve efficiency and reduce costs. Moreover, collaborative AR systems extend applicability, allowing for collaborative environments for different roles. In this paper, we propose a multi-user collaborative AR system (aptly called the “multi-user collaborative system”, or MUCSys); it is composed of three ends—MUCStudio, MUCView, and MUCServer. MUCStudio aims to construct industrial content with CAD model transformation, simplification, database update, marker design, scene editing, and exportation, while MUCView contains sensor data analysis, real-time localization, scene loading, annotation editing, and virtual–real rendering. MUCServer—as the bridge between MUCStudio and MUCView—presents collaborative and database services. To achieve this, we implemented the algorithms of local map establishment, global map registration, optimization, and network synchronization. The system provides AR services for diverse industrial processes via three collaborative ways—remote support, collaborative annotation, and editing. According to the system, applications for cutting machines were presented to improve efficiency and reduce costs, covering cutting head designs, production line sales, and cutting machine inspections. Finally, a user study was performed to prove the usage experience of the system.

Design and Development of Collaborative AR System for Anatomy Training

Background: Augmented Reality (AR) incorporates both real and virtual objects in real-time environments and allows single and multi-users to interact with 3D models. It is often tricky to adopt multi-users in the same environment because of the devices’ latency and model position accuracy in displaying the models simultaneously. Method: To address this concern, we present a multi-user sharing technique in the AR of the human anatomy that increases learning with high quality, high stability, and low latency in multiple devices. Besides, the multi-user interactive display (HoloLens) merges with the human body anatomy application (AnatomyNow) to teach and train students, academic staff, and hospital faculty in the human body anatomy. We also introduce a pin system to share the same knowledge between multiple users. A total of 5 groups have been considered for the study and the evaluation has been performed using two parameters: latency between the devices and position accuracy of the 3D objects in the same environment. Results: The proposed multi-user interaction technique is observed to be good in terms of 3D object position accuracy and latency between the devices. Conclusion: AR technology provides a multi-user interactive environment for teaching and training in the human body anatomy.

The Effectiveness of Collaborative Augmented Reality in Gross Anatomy Teaching: A Quantitative and Qualitative Pilot Study.

In the context of gross anatomy education, novel augmented reality (AR) systems have the potential to serve as complementary pedagogical tools and facilitate interactive, student-centered learning. However, there is a lack of AR systems that enable multiple students to engage in collaborative, team-based learning environments. This article presents the results of a pilot study in which first-year medical students (n=16) had the opportunity to work with such a collaborative AR system during a full-day gross anatomy seminar. Student performance in an anatomy knowledge test, conducted after an extensive group learning session, increased significantly compared to a pre-test in both the experimental group working with the collaborative AR system (P<0.01) and in the control group working with traditional anatomy atlases and three-dimensional (3D) models (P<0.01). However, no significant differences were found between the test results of both groups. While the experienced mental effort during the collaborative learning session was considered rather high (5.13±2.45 on a seven-point Likert scale), both qualitative and quantitative feedback during a survey as well as the results of a System Usability Scale (SUS) questionnaire (80.00±13.90) outlined the potential of the collaborative AR system for increasing students' 3D understanding of topographic anatomy and its advantages over comparable AR systems for single-user experiences. Overall, these outcomes show that collaborative AR systems such as the one evaluated within this work stimulate interactive, student-centered learning in teams and have the potential to become an integral part of a modern, multi-modal anatomy curriculum.

Co-localized augmented human and X-ray observers in collaborative surgical ecosystem.

Image-guided percutaneous interventions are safer alternatives to conventional orthopedic and trauma surgeries. To advance surgical tools in complex bony structures during these procedures with confidence, a large number of images is acquired. While image-guidance is the de facto standard to guarantee acceptable outcome, when these images are presented on monitors far from the surgical site the information content cannot be associated easily with the 3D patient anatomy. In this article, we propose a collaborative augmented reality (AR) surgical ecosystem to jointly co-localize the C-arm X-ray and surgeon viewer. The technical contributions of this work include (1) joint calibration of a visual tracker on a C-arm scanner and its X-ray source via a hand-eye calibration strategy, and (2) inside-out co-localization of human and X-ray observers in shared tracking and augmentation environments using vision-based simultaneous localization and mapping. We present a thorough evaluation of the hand-eye calibration procedure. Results suggest convergence when using 50 pose pairs or more. The mean translation and rotation errors at convergence are 5.7mm and [Formula: see text], respectively. Further, user-in-the-loop studies were conducted to estimate the end-to-end target augmentation error. The mean distance between landmarks in real and virtual environment was 10.8mm. The proposed AR solution provides a shared augmented experience between the human and X-ray viewer. The collaborative surgical AR system has the potential to simplify hand-eye coordination for surgeons or intuitively inform C-arm technologists for prospective X-ray view-point planning.

The Effect of View Independence in a Collaborative AR System

In this paper we describe a system for remote collaboration using Augmented Reality (AR) that supports view independence. The system was designed to allow a remote user to assist a local user in an object placement task. The remote helper can navigate the local user's scene independently from the local user by using a three-dimensional reconstruction of the environment. The remote user can also place virtual annotations in the scene that the local user views through a head mounted display. The system tracks the position of key physical objects and the local user's head pose, displaying both to the remote user. A key advantage of this system compared to other collaborative AR interfaces is that it allows the remote expert to have an independent view into the shared task space. A user study was performed using this system with the users completing a simple mostly two-dimensional object placement task. It was designed to test how the amount of remote view independence affected collaboration. Four conditions were used with varying degrees of view independence. It was found that increased view independence led to faster task completion time, more confidence from users, and a decrease in the amount of time spent communicating verbally during the task. However, varying the view independence did not significantly change the accuracy of the placement of objects. The implications of the results are discussed along with directions for future research.

Server implementations for improving the performance of CAR systems based on mobile phones

Collaborative Augmented Reality (CAR) systems allow multiple users to share a real world environment, including computer-generated images in real time. The hardware features of most current mobile phones include wireless network capabilities that offer a natural platform for CAR systems. However, the potential number of clients in CAR systems based on mobile phones is much larger than on CAR systems based on other kind of mobile devices, requiring a system design that takes into account scalability issues. This paper presents the experimental characterization of CAR systems based on mobile phones, providing quantitative results about well-known performance metrics in distributed systems. The results show that the system saturation point depends on the overall percentage of CPU utilization in the computer platform acting as the system server. Also, the results show that it is limited by the server I/O in some cases. Therefore, this paper also shows different server implementations that can improve the system throughput, as well as a comparative study. The results show that the implementation based on UDP messages provides a significant improvement in system throughput with respect to other implementations based on TCP, at the cost of losing a very small percentage of messages. These results validate this implementation as the most efficient one for large scale CAR applications based on mobile phones.

Comparative performance evaluation of CAR systems based on mobile phones and feature tracking

Collaborative Augmented Reality (CAR) systems based on mobile phones have experienced a huge expansion last years, since the hardware features of most mobile phones provide excellent multimedia services and wireless network capabilities. In previous works, we improved the performance of large-scale CAR systems based on mobile phones that use fiducial marker tracking. However, CAR systems based on natural feature tracking have just emerged, changing the way in which Augmented Reality applications work. In this paper, we propose the performance evaluation of CAR systems based on feature tracking when using mobile phones, and their comparison with CAR systems based on fiducial marker tracking. The evaluation of the whole CAR system includes the rendering of the virtual environment with Unity3D. The purpose is to provide the reader with a reference about the performance that can be achieved with each kind of CAR system. The evaluation results of client devices show that they work faster with natural feature (commonly denoted as markerless) tracking than with fiducial marker tracking, regardless of the phone model and the operating system considered. The evaluation results of the whole CAR system show that natural feature tracking provides similar performance than fiducial marker tracking when the system reaches saturation. However, the use of natural feature tracking allows better performance for low workloads or when the system approaches saturation, since, it provides similar response times at the cost of increasing the percentage of CPU utilization in the server, instead of dropping messages. These results validate natural feature tracking as the best option for CAR systems based on mobile phones.

An investigation of learners' collaborative knowledge construction performances and behavior patterns in an augmented reality simulation system

The purpose of this study was to investigate how a mobile collaborative augmented reality (AR) simulation system affects learners' knowledge construction behaviors and learning performances. In this study, 40 undergraduate students were recruited and divided into dyads to discuss a given task either with the assistance of a mobile collaborative AR system or traditional 2D simulation system. The participants' knowledge acquisition regarding elastic collision was evaluated through a pre-test and a post-test comparison. Learners' knowledge construction behaviors were qualitatively identified according to an adapted three-category coding scheme including construction of problem space (PS), construction of conceptual space (CS), and construction of relations between conceptual and problem space (CPS), and were then analyzed by adopting lag sequential analysis. The results indicated that the learners who learned with the AR system showed significant better learning achievements than those who learned with the traditional 2D simulation system. Furthermore, the sequential patterns of the learners' behaviors were identified, including three sustained loops (PS→PS, CS→CS, CPS→CPS), a bi-directional path between the PS and CPS activities (PS↔CPS), and a one way path from the PS activity to the CS activity (PS→CS). The revealed behavior patterns suggest that the AR Physics system may serve as a supportive tool and enable dyad learners to respond quickly to the displayed results and support their knowledge construction processes to produce a positive outcome. Based on the behavioral patterns found in this study, suggestions for future studies and further modifications to the system are proposed.

Scape: supporting stereoscopic collaboration in augmented and projective environments

Our collaborative augmented reality system for multiple users simultaneously creates outside-in workbench views and inside-out life-size walkthrough views, bridging the virtual and augmented reality paradigms. Here we introduce a collaborative infrastructure - stereoscopic collaboration in augmented and projective environments(Scape). Scape seamlessly merges the paradigm of virtual reality with that of augmented reality in a single system and provides multimodality interface devices and unique widget interfaces to facilitate collaborative work in 3D environments. A custom-designed cross-platform application-programming interface (API) allows high and medium-level controls over the Scape workspace to enable augmented interaction and collaboration.

Mathematics and geometry education with collaborative augmented reality

Construct3D is a 3D geometric construction tool specifically designed for mathematics and geometry education. It is based on the mobile collaborative augmented reality system “Studierstube”. We describe our efforts in developing a system for the improvement of spatial abilities and maximization of transfer of learning. In order to support various teacher–student interaction scenarios we implemented flexible methods for context and user dependent rendering of parts of the construction. Together with hybrid hardware setups they allow the use of Construct3D in today's classrooms and provide a testbed for future evaluations. Means of application and integration in mathematics and geometry education at high school as well as university level are being discussed. Anecdotal evidence supports our claim that Construct3D is easy to learn, encourages experimentation with geometric constructions and improves spatial skills.

MagicMeeting: A Collaborative Tangible Augmented Reality System

We describe an augmented reality (AR) system that allows multiple participants to interact with 2D and 3D data using tangible user interfaces. The system features face-to-face communication, collaborative viewing and manipulation of 3D models, and seamless access to 2D desktop applications within the shared 3D space. All virtual content, including 3D models and 2D desktop windows, is attached to tracked physical objects in order to leverage the efficiencies of natural two-handed manipulation. The presence of 2D desktop space within 3D facilitates data exchange between the two realms, enables control of 3D information by 2D applications, and generally increases productivity by providing access to familiar tools. We present a general concept for a collaborative tangible AR system, including a comprehensive set of interaction techniques, a distributed hardware setup, and a component-based software architecture that can be flexibly configured using XML. We show the validity of our concept with an implementation of an application scenario from the automotive industry.

Construct3D: A Virtual Reality Application for Mathematics and Geometry Education

Construct3D is a three dimensional geometric construction tool based on the collaborative augmented reality system ‘Studierstube’. Our setup uses a stereoscopic head mounted display (HMD) and the Personal Interaction Panel (PIP) - a two-handed 3D interaction tool that simplifies 3D model interaction. Means of application in mathematics and geometry education at high school as well as university level are being discussed. A pilot study summarizes the strengths and possible extensions of our system. Anecdotal evidence supports our claim that the use of Construct3D is easy to learn and encourages experimentation with geometric constructions.