A Virtual Testbed for Fish-Tank Virtual Reality: Improving Calibration with a Virtual-in-Virtual Display

With the development of novel calibration techniques for multimedia projectors and curved projection surfaces, volumetric 3D displays are becoming easier and more affordable to build. The basic requirements include a display shape that defines the volume (e.g. a sphere, cylinder, or cuboid) and a tracking system to provide each user's location for the perspective corrected rendering. When coupled with modern graphics cards, these displays are capable of high resolution, low latency, high frame rate, and even stereoscopic rendering; however, like many previous studies have shown, every component must be precisely calibrated for a compelling 3D effect. While human perceptual requirements have been extensively studied for head-tracked displays, most studies featured seated users in front of a flat display. It remains unclear if results from these flat display studies are applicable to newer, walk-around displays with enclosed or curved shapes. To investigate these issues, we developed a virtual testbed for volumetric head-tracked displays that can measure calibration accuracy of the entire system in real-time. We used this testbed to investigate visual distortions of prototype curved displays, improve existing calibration techniques, study the importance of stereo to performance and perception, and validate perceptual calibration with novice users. Our experiments show that stereo is important for task performance, but requires more accurate calibration, and that novice users can make effective use of perceptual calibration tools. We also propose a novel, real-time calibration method that can be used to fine-tune an existing calibration using perceptual feedback. The findings from this work can be used to build better head-tracked volumetric displays with an unprecedented amount of 3D realism and intuitive calibration tools for novice users

Development of a handheld fiber-optic probe-based raman imaging instrumentation: raman chemlighter

Raman systems based on handheld fiber-optic probes offer advantages in terms of smaller sizes and easier access to the measurement sites, which are favorable for biomedical and clinical applications in the complex environment. However, there are several common drawbacks of applying probes for many applications: (1) The fixed working distance requires the user to maintain a certain working distance to acquire higher Raman signals; (2) The single-point-measurement ability restricts realizing a mapping or scanning procedure; (3) Lack of real-time data processing and a straightforward co-registering method to link the Raman information with the respective measurement position. The thesis proposed and experimentally demonstrated various approaches to overcome these drawbacks. A handheld fiber-optic Raman probe with an autofocus unit was presented to overcome the problem arising from using fixed-focus lenses, by using a liquid lens as the objective lens, which allows dynamical adjustment of the focal length of the probe. An implementation of a computer vision-based positional tracking to co-register the regular Raman spectroscopic measurements with the spatial location enables fast recording of a Raman image from a large tissue sample by combining positional tracking of the laser spot through brightfield images. The visualization of the Raman image has been extended to augmented and mixed reality and combined with a 3D reconstruction method and projector-based visualization to offer an intuitive and easily understandable way of presenting the Raman image. All these advances are substantial and highly beneficial to further drive the clinical translation of Raman spectroscopy as potential image-guided instrumentation

Imaging methods for understanding and improving visual training in the geosciences

Experience in the field is a critical educational component of every student studying geology. However, it is typically difficult to ensure that every student gets the necessary experience because of monetary and scheduling limitations. Thus, we proposed to create a virtual field trip based off of an existing 10-day field trip to California taken as part of an undergraduate geology course at the University of Rochester. To assess the effectiveness of this approach, we also proposed to analyze the learning and observation processes of both students and experts during the real and virtual field trips. At sites intended for inclusion in the virtual field trip, we captured gigapixel resolution panoramas by taking hundreds of images using custom built robotic imaging systems. We gathered data to analyze the learning process by fitting each geology student and expert with a portable eye- tracking system that records a video of their eye movements and a video of the scene they are observing. An important component of analyzing the eye-tracking data requires mapping the gaze of each observer into a common reference frame. We have made progress towards developing a software tool that helps automate this procedure by using image feature tracking and registration methods to map the scene video frames from each eye-tracker onto a reference panorama for each site. For the purpose of creating a virtual field trip, we have a large scale semi-immersive display system that consists of four tiled projectors, which have been colorimetrically and photometrically calibrated, and a curved widescreen display surface. We use this system to present the previously captured panoramas, which simulates the experience of visiting the sites in person. In terms of broader geology education and outreach, we have created an interactive website that uses Google Earth as the interface for visually exploring the panoramas captured for each site

A reciprocal 360-degree 3D light-field image acquisition and display system

A reciprocal 360-degree three-dimensional light-field image acquisition and display system was designed using a common catadioptric optical configuration and a lens array. Proof-of-concept experimental setups were constructed with a full capturing part and a truncated display section to demonstrate that the proposed design works without loss of generality. Unlike conventional setups, which record and display rectangular volumes, the proposed configuration records 3D images from its surrounding spherical volume in the capture mode and project 3D images to the same spherical volume in the display mode. This is particularly advantageous in comparison to other 360-degree multi-camera and multiple projector display systems which require extensive image and physical calibration. We analysed the system and showed the quality measures such as angular resolution and space bandwidth product based on design parameters. The issue due to the pixel size difference between the available imaging sensor and the display was also addressed. A diffractive microlens array matching the sensor size is used in the acquisition part whereas a vacuum cast lens array matching the display size is used in the display part with scaled optics. The experimental results demonstrate the proposed system design works well and in good agreement with the simulation results.CAPE Acorn 2017 Awar

MoSART: Mobile Spatial Augmented Reality for 3D Interaction With Tangible Objects

In this paper we introduce MoSART, a novel approach for Mobile Spatial Augmented Reality on Tangible objects. MoSART is dedicated to mobile interaction with tangible objects in single or collaborative situations. It is based on a novel “all-in-one” Head-Mounted Display (AMD) including a projector (for the SAR display) and cameras (for the scene registration). Equipped with the HMD the user is able to move freely around tangible objects and manipulate them at will. The system tracks the position and orientation of the tangible 3D objects and projects virtual content over them. The tracking is a feature-based stereo optical tracking providing high accuracy and low latency. A projection mapping technique is used for the projection on the tangible objects which can have a complex 3D geometry. Several interaction tools have also been designed to interact with the tangible and augmented content, such as a control panel and a pointer metaphor, which can benefit as well from the MoSART projection mapping and tracking features. The possibilities offered by our novel approach are illustrated in several use cases, in single or collaborative situations, such as for virtual prototyping, training or medical visualization

Roomalive: Magical experiences enabled by scalable, adaptive projector-camera units

ABSTRACT RoomAlive is a proof-of-concept prototype that transforms any room into an immersive, augmented entertainment experience. Our system enables new interactive projection mapping experiences that dynamically adapts content to any room. Users can touch, shoot, stomp, dodge and steer projected content that seamlessly co-exists with their existing physical environment. The basic building blocks of RoomAlive are projector-depth camera units, which can be combined through a scalable, distributed framework. The projector-depth camera units are individually autocalibrating, self-localizing, and create a unified model of the room with no user intervention. We investigate the design space of gaming experiences that are possible with RoomAlive and explore methods for dynamically mapping content based on room layout and user position. Finally we showcase four experience prototypes that demonstrate the novel interactive experiences that are possible with RoomAlive and discuss the design challenges of adapting any game to any room

Spatially Aware Computing for Natural Interaction

Spatial information refers to the location of an object in a physical or digital world. Besides, it also includes the relative position of an object related to other objects around it. In this dissertation, three systems are designed and developed. All of them apply spatial information in different fields. The ultimate goal is to increase the user friendliness and efficiency in those applications by utilizing spatial information. The first system is a novel Web page data extraction application, which takes advantage of 2D spatial information to discover structured records from a Web page. The extracted information is useful to re-organize the layout of a Web page to fit mobile browsing. The second application utilizes the 3D spatial information of a mobile device within a large paper-based workspace to implement interactive paper that combines the merits of paper documents and mobile devices. This application can overlay digital information on top of a paper document based on the location of a mobile device within a workspace. The third application further integrates 3D space information with sound detection to realize an automatic camera management system. This application automatically controls multiple cameras in a conference room, and creates an engaging video by intelligently switching camera shots among meeting participants based on their activities. Evaluations have been made on all three applications, and the results are promising. In summary, this dissertation comprehensively explores the usage of spatial information in various applications to improve the usability

Augmented Reality

Augmented Reality (AR) is a natural development from virtual reality (VR), which was developed several decades earlier. AR complements VR in many ways. Due to the advantages of the user being able to see both the real and virtual objects simultaneously, AR is far more intuitive, but it's not completely detached from human factors and other restrictions. AR doesn't consume as much time and effort in the applications because it's not required to construct the entire virtual scene and the environment. In this book, several new and emerging application areas of AR are presented and divided into three sections. The first section contains applications in outdoor and mobile AR, such as construction, restoration, security and surveillance. The second section deals with AR in medical, biological, and human bodies. The third and final section contains a number of new and useful applications in daily living and learning