274 research outputs found
Improving command selection in smart environments by exploiting spatial constancy
With the a steadily increasing number of digital devices, our environments are becoming increasingly smarter: we can now use our tablets to control our TV, access our recipe database while cooking, and remotely turn lights on and off. Currently, this Human-Environment Interaction (HEI) is limited to in-place interfaces, where people have to walk up to a mounted set of switches and buttons, and navigation-based interaction, where people have to navigate on-screen menus, for example on a smart-phone, tablet, or TV screen. Unfortunately, there are numerous scenarios in which neither of these two interaction paradigms provide fast and convenient access to digital artifacts and system commands. People, for example, might not want to touch an interaction device because their hands are dirty from cooking: they want device-free interaction. Or people might not want to have to look at a screen because it would interrupt their current task: they want system-feedback-free interaction. Currently, there is no interaction paradigm for smart environments that allows people for these kinds of interactions.
In my dissertation, I introduce Room-based Interaction to solve this problem of HEI. With room-based interaction, people associate digital artifacts and system commands with real-world objects in the environment and point toward these real-world proxy objects for selecting the associated digital artifact. The design of room-based interaction is informed by a theoretical analysis of navigation- and pointing-based selection techniques, where I investigated the cognitive systems involved in executing a selection. An evaluation of room-based interaction in three user studies and a comparison with existing HEI techniques revealed that room-based interaction solves many shortcomings of existing HEI techniques: the use of real-world proxy objects makes it easy for people to learn the interaction technique and to perform accurate pointing gestures, and it allows for system-feedback-free interaction; the use of the environment as flat input space makes selections fast; the use of mid-air full-arm pointing gestures allows for device-free interaction and increases awareness of other’s interactions with the environment.
Overall, I present an alternative selection paradigm for smart environments that is superior to existing techniques in many common HEI-scenarios. This new paradigm can make HEI more user-friendly, broaden the use cases of smart environments, and increase their acceptance for the average user
TRAINING AND ASSESSMENT OF HAND-EYE COORDINATION WITH ELECTROENCEPHALOGRAPHY
Ph.DDOCTOR OF PHILOSOPH
Augmented reality device for first response scenarios
A prototype of a wearable computer system is proposed and implemented using commercial off-shelf components. The system is designed to allow the user to access location-specific information about an environment, and to provide capability for user tracking. Areas of applicability include primarily first response scenarios, with possible applications in maintenance or construction of buildings and other structures. Necessary preparation of the target environment prior to system\u27s deployment is limited to noninvasive labeling using optical fiducial markers. The system relies on computational vision methods for registration of labels and user position. With the system the user has access to on-demand information relevant to a particular real-world location. Team collaboration is assisted by user tracking and real-time visualizations of team member positions within the environment. The user interface and display methods are inspired by Augmented Reality1 (AR) techniques, incorporating a video-see-through Head Mounted Display (HMD) and fingerbending sensor glove.*.
1Augmented reality (AR) is a field of computer research which deals with the combination of real world and computer generated data. At present, most AR research is concerned with the use of live video imagery which is digitally processed and augmented by the addition of computer generated graphics. Advanced research includes the use of motion tracking data, fiducial marker recognition using machine vision, and the construction of controlled environments containing any number of sensors and actuators. (Source: Wikipedia) *This dissertation is a compound document (contains both a paper copy and a CD as part of the dissertation). The CD requires the following system requirements: Adobe Acrobat; Microsoft Office; Windows MediaPlayer or RealPlayer
Augmented reality and scene examination
The research presented in this thesis explores the impact of Augmented Reality on human performance, and compares this technology with Virtual Reality using a head-mounted video-feed for a variety of tasks that relate to scene examination. The motivation for the work was the question of whether Augmented Reality could provide a vehicle for training in crime scene investigation. The Augmented Reality application was developed using fiducial markers in the Windows Presentation Foundation, running on a wearable computer platform; Virtual Reality was developed using the Crytek game engine to present a photo-realistic 3D environment; and a video-feed was provided through head-mounted webcam. All media were presented through head-mounted displays of similar resolution to provide the sole source of visual information to participants in the experiments. The experiments were designed to increase the amount of mobility required to conduct the search task, i.e., from rotation in the horizontal or vertical plane through to movement around a room. In each experiment, participants were required to find objects and subsequently recall their location. It is concluded that human performance is affected not merely via the medium through which the world is perceived but moreover, the constraints governing how movement in the world is controlled
Investigating Precise Control in Spatial Interactions: Proxemics, Kinesthetics, and Analytics
Augmented and Virtual Reality (AR/VR) technologies have reshaped the way in which we perceive the virtual world. In fact, recent technological advancements provide experiences that make the physical and virtual worlds almost indistinguishable. However, the physical world affords subtle sensorimotor cues which we subconsciously utilize to perform simple and complex tasks in our daily lives. The lack of this affordance in existing AR/VR systems makes it difficult for their mainstream adoption over conventional user interfaces. As a case in point, existing spatial user interfaces (SUI) lack the intuition to perform tasks in a manner that is perceptually familiar to the physical world. The broader goal of this dissertation lies in facilitating an intuitive spatial manipulation experience, specifically for motor control.
We begin by investigating the role of proximity to an action on precise motor control in spatial tasks. We do so by introducing a new SUI called the Clock-Maker's Work-Space (CMWS), with the goal of enabling precise actions close to the body, akin to the physical world. On evaluating our setup in comparison to conventional mixed-reality interfaces, we find CMWS to afford precise actions for bi-manual spatial tasks. We further compare our SUI with a physical manipulation task and observe similarities in user behavior across both tasks.
We subsequently narrow our focus on studying precise spatial rotation. We utilize haptics, specifically force-feedback (kinesthetics) for augmenting fine motor control in spatial rotational task. By designing three kinesthetic rotation metaphors, we evaluate precise rotational control with and without haptic feedback for 3D shape manipulation. Our results show that haptics-based rotation algorithms allow for precise motor control in 3D space, also, help reduce hand fatigue.
In order to understand precise control in its truest form, we investigate orthopedic surgery training from the point of analyzing bone-drilling tasks. We designed a hybrid physical-virtual simulator for bone-drilling training and collected physical data for analyzing precise drilling action. We also developed a Laplacian based performance metric to help expert surgeons evaluate the resident training progress across successive years of orthopedic residency
An investigation of performer embodiment and performative interaction on an augmented stage
This thesis concerns itself with an investigation of live performance on an augmented stage in front of an audience, where performers witness themselves as projection mapped virtual characters able to interact with projected virtual scenography. An interactive virtual character is projected onto the body of a performer, its movements congruent with the performer. Through visual feedback via a Head Mounted Display (HMD), the performer is virtually embodied in that they witness their virtualised body interacting with the virtual scenery and props of the augmented stage.
The research is informed by a theoretical framework derived from theory on intermediality and performance, virtual embodiment and performative interaction. A literature review of theatrical productions and performances utilising projection identifies a research gap of providing the performer with a visual perspective of themselves in relationship to the projected scenography. The visual perspective delivered via the HMD enables the performer to perform towards the audience and away from the interactive projected backdrop. The resultant ‘turn away’ from facing an interactive screen and instead performing towards an audience is encapsulated in the concept of the ‘Embodied Performative Turn’.
The practice-based research found that changing the visual perspective presented to the performer impacted differently on performative interaction and virtual embodiment. A second-person or audience perspective, ‘performer-as-observed’ prioritises the perception of the virtual body and enhances performative behaviour but challenges effective performative interaction with the virtual scenography. Conversely, a first-person perspective, ‘performer-as-observer’ prioritises a worldview and enhances performative interaction, but negatively impacts on performative behaviour with the loss of performer-as-observed.
The research findings suggest that the presentation of differing perspectives to the performer can be used to selectively enhance performative interaction and performative behaviour on an augmented stage
Design of virtual reality systems for animal behavior research
Virtual reality (VR) experimental behavior setups enable cognitive neuroscientists to study the integration of visual depth cues and self-motion cues into a single percept of three-dimensional space. Rodents can navigate a virtual environment by running on a spherical treadmill, but simulating locomotion in this way can both bias and suppress the frequency of their behaviors as well as introduce vestibulomotor and vestibulovisual sensory conflict during locomotion. Updating the virtual environment via the subject's own freely-moving head movements solves both the naturalistic behavior bias and vestibular conflict issues. In this thesis, I review elements of self-motion and 3D scene perception that contribute to a sense of immersion in virtual environments and suggest a freely-moving CAVE system as a VR solution for low-artifact neuroscience experiments. The manuscripts describing the 3D graphics Python package and the virtual reality setup are included. In this freely-moving CAVE VR setup, freely-moving rats demonstrate immersion in virtual environments by displaying height aversion to virtual cliffs, exploration preference of virtual objects, and spontaneously modify their locomotion trajectories near virtual walls. These experiments help bridge the classic behavior and virtual reality literature by showing that rats display similar behaviors to virtual environment features without training
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Augmented Reality Interfaces for Enabling Fast and Accurate Task Localization
Changing viewpoints is a common technique to gain additional visual information about the spatial relations among the objects contained within an environment. In many cases, all of the necessary visual information is not available from a single vantage point, due to factors such as occlusion, level of detail, and limited field of view. In certain instances, strategic viewpoints may need to be visited multiple times (e.g., after each step of an iterative process), which makes being able to transition between viewpoints precisely and with minimum effort advantageous for improved task performance (e.g., faster completion time, fewer errors, less dependence on memory).
Many augmented reality (AR) applications are designed to make tasks easier to perform by supplementing a user's first-person view with virtual instructions. For those tasks that benefit from being seen from more than a single viewpoint, AR users typically have to physically relocalize (i.e., move a see-through display and typically themselves since those displays are often head-worn or hand-held) to those additional viewpoints. However, this physical motion may be costly or difficult, due to increased distances or obstacles in the environment.
We have developed a set of interaction techniques that enable fast and accurate task localization in AR. Our first technique, SnapAR, allows users to take snapshots of augmented scenes that can be virtually revisited at later times. The system stores still images of scenes along with camera poses, so that augmentations remain dynamic and interactive. Our prototype implementation features a set of interaction techniques specifically designed to enable quick viewpoint switching. A formal evaluation of the capability to manipulate virtual objects within snapshot mode showed significant savings in time spent and gain in accuracy when compared to physically traveling between viewpoints.
For cases when a user has to physically travel to a strategic viewpoint (e.g., to perform maintenance and repair on a large physical piece of equipment), we present ParaFrustum, a geometric construct that represents this set of strategic viewpoints and viewing directions and establishes constraints on a range of acceptable locations for the user's eyes and a range of acceptable angles in which the user's head can be oriented. Providing tolerance in the allowable viewing positions and directions avoids burdening the user with the need to assume a tightly constrained 6DOF pose when it is not required by the task. We describe two visualization techniques, ParaFrustum-InSitu and ParaFrustum-HUD, that guide a user to assume one of the poses defined by a ParaFrustum. A formal user study corroborated that speed improvements increase with larger tolerances and reveals interesting differences in participant trajectories based on the visualization technique.
When the object to be operated on is smaller and can be handheld, instead of being large and stationary, it can be manually rotated instead of the user moving to a strategic viewpoint. Examples of such situations include tasks in which one object must be oriented relative to a second prior to assembly and tasks in which objects must be held in specific ways to inspect them. Researchers have investigated guidance mechanisms for some 6DOF tasks, using wide--field-of-view (FOV), stereoscopic virtual and augmented reality head-worn displays (HWDs). However, there has been relatively little work directed toward smaller FOV lightweight monoscopic HWDs, such as Google Glass, which may remain more comfortable and less intrusive than stereoscopic HWDs in the near future. In our Orientation Assistance work, we have designed and implemented a novel visualization approach and three additional visualizations representing different paradigms for guiding unconstrained manual 3DOF rotation, targeting these monoscopic HWDs. This chapter includes our exploration of these paradigms and the results of a user study evaluating the relative performance of the visualizations and showing the advantages of our new approach.
In summary, we investigated ways of enabling an AR user to obtain visual information from multiple viewpoints, both physically and virtually. In the virtual case, we showed how one can change viewpoints precisely and with less effort. In the physical case, we explored how we can interactively guide users to obtain strategic viewpoints, either by moving their heads or re-orienting handheld objects. In both cases, we showed that our techniques help users accomplish certain types of tasks more quickly and with fewer errors, compared to when they have to change viewpoints following alternative, previously suggested methods
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