Learning 3D Navigation Protocols on Touch Interfaces with Cooperative Multi-Agent Reinforcement Learning

Using touch devices to navigate in virtual 3D environments such as computer assisted design (CAD) models or geographical information systems (GIS) is inherently difficult for humans, as the 3D operations have to be performed by the user on a 2D touch surface. This ill-posed problem is classically solved with a fixed and handcrafted interaction protocol, which must be learned by the user. We propose to automatically learn a new interaction protocol allowing to map a 2D user input to 3D actions in virtual environments using reinforcement learning (RL). A fundamental problem of RL methods is the vast amount of interactions often required, which are difficult to come by when humans are involved. To overcome this limitation, we make use of two collaborative agents. The first agent models the human by learning to perform the 2D finger trajectories. The second agent acts as the interaction protocol, interpreting and translating to 3D operations the 2D finger trajectories from the first agent. We restrict the learned 2D trajectories to be similar to a training set of collected human gestures by first performing state representation learning, prior to reinforcement learning. This state representation learning is addressed by projecting the gestures into a latent space learned by a variational auto encoder (VAE).Comment: 17 pages, 8 figures. Accepted at The European Conference on Machine Learning and Principles and Practice of Knowledge Discovery in Databases 2019 (ECMLPKDD 2019

A Content-Analysis Approach for Exploring Usability Problems in a Collaborative Virtual Environment

As Virtual Reality (VR) products are becoming more widely available in the consumer market, improving the usability of these devices and environments is crucial. In this paper, we are going to introduce a framework for the usability evaluation of collaborative 3D virtual environments based on a large-scale usability study of a mixedmodality collaborative VR system. We first review previous literature about important usability issues related to collaborative 3D virtual environments, supplemented with our research in which we conducted 122 interviews after participants solved a collaborative virtual reality task. Then, building on the literature review and our results, we extend previous usability frameworks. We identified twelve different usability problems, and based on the causes of the problems, we grouped them into three main categories: VR environment-, device interaction-, and task-specific problems. The framework can be used to guide the usability evaluation of collaborative VR environments

Pictures in Your Mind: Using Interactive Gesture-Controlled Reliefs to Explore Art

Tactile reliefs offer many benefits over the more classic raised line drawings or tactile diagrams, as depth, 3D shape, and surface textures are directly perceivable. Although often created for blind and visually impaired (BVI) people, a wider range of people may benefit from such multimodal material. However, some reliefs are still difficult to understand without proper guidance or accompanying verbal descriptions, hindering autonomous exploration. In this work, we present a gesture-controlled interactive audio guide (IAG) based on recent low-cost depth cameras that can be operated directly with the hands on relief surfaces during tactile exploration. The interactively explorable, location-dependent verbal and captioned descriptions promise rapid tactile accessibility to 2.5D spatial information in a home or education setting, to online resources, or as a kiosk installation at public places. We present a working prototype, discuss design decisions, and present the results of two evaluation studies: the first with 13 BVI test users and the second follow-up study with 14 test users across a wide range of people with differences and difficulties associated with perception, memory, cognition, and communication. The participant-led research method of this latter study prompted new, significant and innovative developments

Smartphone Based 3D Navigation Techniques in an Astronomical Observatory Context: Implementation and Evaluation in a Software Platform

International audience3D Virtual Environments (3DVE) come up as a good solution to transmit knowledge in a museum exhibit. In such contexts, providing easy to learn and to use interaction techniques which facilitate the handling inside a 3DVE is crucial to maximize the knowledge transfer. We took the opportunity to design and implement a software platform for explaining the behavior of the Telescope Bernard-Lyot to museum visitors on top of the Pic du Midi. Beyond the popularization of a complex scientific equipment, this platform constitutes an open software environment to easily plug different 3D interaction techniques. Recently, popular use of a smartphones as personal handled computer lets us envision the use of a mobile device as an interaction support with these 3DVE. Accordingly, we design and propose how to use the smartphone as a tangible object to navigate inside a 3DVE. In order to prove the interest in the use of smartphones, we compare our solution with available solutions: keyboard-mouse and 3D mouse. User experiments confirmed our hypothesis and particularly emphasizes that visitors find our solution more attractive and stimulating. Finally, we illustrate the benefits of our software framework by plugging alternative interaction techniques for supporting selection and manipulation task in 3D

From Multi-User Virtual Environment to 3D Virtual Learning Environment

While digital virtual worlds have been used in education for a number of years, advances in the capabilities and spread of technology have fed a recent boom in interest in massively multi‐user 3D virtual worlds for entertainment, and this in turn has led to a surge of interest in their educational applications. In this paper we briefly review the use of virtual worlds for education, from informal learning to formal instruction, and consider what is required to turn a virtual world from a Multi‐User Virtual Environment into a fully fledged 3D Virtual Learning Environment (VLE). In this we focus on the development of Sloodle – a system which integrates the popular 3D virtual world of Second Life with the open‐source VLE Moodle. Our intent is not simply to provide additional learning support features for Second Life, but to study more generally the ways in which integrated virtual environments can benefit teaching and learning, and this is the focus of our closing discussion

When gestures show us the way: Co-speech gestures selectively facilitate navigation and spatial memory.

How does gesturing during route learning relate to subsequent spatial performance? We examined the relationship between gestures produced spontaneously while studying route directions and spatial representations of the navigated environment. Participants studied route directions, then navigated those routes from memory in a virtual environment, and finally had their memory of the environment assessed. We found that, for navigators with low spatial perspective-taking performance on the Spatial Orientation Test, more gesturing from a survey perspective predicted more accurate memory following navigation. Thus, co-thought gestures accompanying route learning relate to performance selectively, depending on the gesturers’ spatial ability and the perspective of their gestures. Survey gestures may help some individuals visualize an overall route that they can retain in memory

The Effects of Finger-Walking in Place (FWIP) on Spatial Knowledge Acquisition in Virtual Environments

Spatial knowledge, necessary for efficient navigation, comprises route knowledge (memory of landmarks along a route) and survey knowledge (overall representation like a map). Virtual environments (VEs) have been suggested as a power tool for understanding some issues associated with human navigation, such as spatial knowledge acquisition. The Finger-Walking-in-Place (FWIP) interaction technique is a locomotion technique for navigation tasks in immersive virtual environments (IVEs). The FWIP was designed to map a human’s embodied ability overlearned by natural walking for navigation, to finger-based interaction technique. Its implementation on Lemur and iPhone/iPod Touch devices was evaluated in our previous studies. In this paper, we present a comparative study of the joystick’s flying technique versus the FWIP. Our experiment results show that the FWIP results in better performance than the joystick’s flying for route knowledge acquisition in our maze navigation tasks

Tangible user interfaces : past, present and future directions

In the last two decades, Tangible User Interfaces (TUIs) have emerged as a new interface type that interlinks the digital and physical worlds. Drawing upon users' knowledge and skills of interaction with the real non-digital world, TUIs show a potential to enhance the way in which people interact with and leverage digital information. However, TUI research is still in its infancy and extensive research is required in or- der to fully understand the implications of tangible user interfaces, to develop technologies that further bridge the digital and the physical, and to guide TUI design with empirical knowledge. This paper examines the existing body of work on Tangible User In- terfaces. We start by sketching the history of tangible user interfaces, examining the intellectual origins of this field. We then present TUIs in a broader context, survey application domains, and review frame- works and taxonomies. We also discuss conceptual foundations of TUIs including perspectives from cognitive sciences, phycology, and philoso- phy. Methods and technologies for designing, building, and evaluating TUIs are also addressed. Finally, we discuss the strengths and limita- tions of TUIs and chart directions for future research