Pietro Neroni

Natural Interaction and Wearable Augmented Reality for the Enjoyment of the Cultural Heritage in Outdoor Conditions

In this paper, a first prototype of a wearable, interactive augmented reality (AR) system for the enjoyment of the cultural heritage in outdoor environments, is presented. By using a binocular see-through display and a time-of-flight (ToF) depth sensor, the system provides the users with a visual augmentation of their surroundings and with touchless interaction techniques to interact with synthetic elements overlapping with the real world. The papers describes the hardware and software system components, and details the interface specifically designed for a socially acceptable cultural heritage exploration. Furthermore, the paper discusses the lesson learned from the first public presentation of the prototype we have carried out in Naples, Italy.

Touchless Target Selection Techniques for Wearable Augmented Reality Systems

The paper deals with target selection techniques for wearable augmented reality systems. In particular, we focus on the three techniques most commonly used in distant freehand pointing and clicking on large displays: wait to click, air tap and thumb trigger. The paper details the design of the techniques for a touchless augmented reality interface and provides the results of a preliminary usability evaluation carried out in out-of-lab settings.

Experiencing touchless interaction with augmented content on wearable head-mounted displays in cultural heritage applications

The cultural heritage could benefit significantly from the integration of wearable augmented reality (AR). This technology has the potential to guide the user and provide her with both in-depth information, without distracting her from the context, and a natural interaction, which can further allow her to explore and navigate her way through a huge amount of cultural information. The integration of touchless interaction and augmented reality is particularly challenging. On the technical side, the human–machine interface has to be reliable so as to guide users across the real world, which is composed of cluttered backgrounds and severe changes in illumination conditions. On the user experience side, the interface has to provide precise interaction tools while minimizing the perceived task difficulty. In this study, an interactive wearable AR system to augment the environment with cultural information is described. To confer robustness to the interface, a strategy that takes advantage of both depth and color data to find the most reliable information on each single frame is introduced. Moreover, the results of an ISO 9241-9 user study performed in both indoor and outdoor conditions are presented and discussed. The experimental results show that, by using both depth and color data, the interface can behave consistently in different indoor and outdoor scenarios. Furthermore, the results show that the presence of a virtual pointer in the augmented visualization significantly reduces the users error rate in selection tasks.

Evaluation of spatial interaction techniques for virtual heritage applications

The increasing use of information and communication technologies (ICT) in museums is providing curators with new opportunities for the display of cultural heritage content, making it possible to merge real and digital works of art in a coherent exhibition space. However, humans learn and perceive by following an interactive process, a fact that is particularly true in relation to the understanding, analysis and interpretation of the cultural heritage. In order to allow visitors to fully exploit the potential of this new hybrid cultural communication, interactivity is essential. This paper analyzes interaction design focusing on a holographic projection system equipped with a gesture-based interface and discussing the results of both quantitative and qualitative user studies aimed at empirically investigating users preferences in relation to interaction techniques when used in a museum context. The experimental findings suggest the adoption of task-specific patterns in the design of touchless user interfaces for the exploration of digital heritage content. Interaction design of a holographic projection system for use in a museum context.Design of task- and domain-specific touchless interaction techniques.Quantitative and qualitative user studies.

Usability Evaluation of a Wearable Augmented Reality System for the Enjoyment of the Cultural Heritage

The recent availability of low cost wearable augmented reality (WAR) technologies is leveraging the design of applications in the cultural heritage domain in order to support users in their emotional journey among the cultural artefacts and monuments of a city. In this paper, we describe a user study evaluating the usability of a wearable augmented reality touchless interface for the enjoyment of the cultural heritage in outdoor environments. The usability evaluation has been carried out in out-of-lab settings with inexperienced users, during a three day exhibition in the city of Naples. The presented results are related to the ease of use and learning of the system, and to the users satisfaction in the enjoyment of the system.

Robust fingertip detection in egocentric vision under varying illumination conditions

Wearable augmented reality (AR) systems have the potential to significantly lower the barriers to accessing information, while leaving the focus of the users attention on the real world. To reveal their true potential, the human-machine interface is crucial. A touchless point-and-click interface for wearable AR systems may be suitable for use in many real-world applications, but it demands fingertip detection techniques robust enough to cope with cluttered backgrounds and varying illumination conditions. In this paper we propose an approach that, by automatically choosing between color and depth features, allows to detect the hand and then the users fingertip both in indoor and outdoor scenarios, with or without adequate illumination.

An Investigation of Leap Motion Based 3D Manipulation Techniques for Use in Egocentric Viewpoint

In this paper we investigate suitable 3D manipulation techniques for a new generation of depth trackers exploitable in ego-vision for an immersive virtual environment. After presenting the specific configuration and hardware used, the paper focuses on an investigation into the advantages and disadvantages of the various techniques in order to choose the one most suitable for the manipulation of an object in an immersive virtual environment. We have faced the problem of canonical manipulation which includes, besides the selection, the positioning and rotation. Two different approaches are described allowing respectively a direct or constrained manipulation of the virtual object. Our aim is to evaluate the perceived usability of the two proposed manipulation techniques in the specific configuration and for this reason qualitative data have been gathered using the System Usability Scale questionnaire. The results show a different level of difficulty perceived by the testers between the two canonical manipulation techniques and a general preference for techniques that prove to be less tiring.

Design and Preliminary Evaluation of Free-Hand Travel Techniques for Wearable Immersive Virtual Reality Systems with Egocentric Sensing

The recent availability of low cost wearable displays coupled with contactless motion sensing devices is leveraging the design of immersive and highly interactive virtual environments. In such virtual worlds, the human-computer interface, and particularly the navigation technique, plays a crucial role. This paper presents a preliminary evaluation of traveling constraints in egocentric vision. In more detail, we describe and compare in an ego-vision scenario two travel techniques, both based on a combination of visual controls and hand gestures but proving to be different in terms of the number of travel directions allowed to the user and of the travel velocity control. The experimental results indicate that, despite the users appreciating the possibility of controlling the travel direction with both head and arrows, not all the directions are considered useful in the same way. However, direct control of the velocity proves to affect positively the navigation experience in all the considered scenarios.

The Vive Controllers vs. Leap Motion for Interactions in Virtual Environments: A Comparative Evaluation

In recent years, virtual reality technologies have been improving in terms of resolution, convenience and portability, fostering their adoption in real life applications. The Vive Controllers and Leap Motion are two of the most commonly used low-cost input devices for interactions in virtual environments. This paper discusses their differences in terms of interaction design, and presents the results of a user study focusing on manipulation tasks, namely Walking box and blocks, Block tower and Numbered cubes tasks, taking into account both quantitative and qualitative observations. The experimental findings show a general preference for the Vive Controllers, but also highlight that further work is needed to simplify complex tasks.

Touchless Disambiguation Techniques for Wearable Augmented Reality Systems

The paper concerns target disambiguation techniques in egocentric vision for wearable augmented reality systems. In particular, the paper focuses on two of the most commonly used selection techniques in immersive environments: Depth Ray and SQUAD. The design and implementation of such techniques in a touchless augmented reality interface, together with the results of a preliminary usability evaluation carried out with inexpert users, are discussed. The user study provides insights on users’ preferences when dealing with the precision-velocity trade-off in selection tasks, carried out in an augmented reality scenario.