{3D} Morphable Face Models -- Past, Present and Future

In this paper, we provide a detailed survey of 3D Morphable Face Models over the 20 years since they were first proposed. The challenges in building and applying these models, namely capture, modeling, image formation, and image analysis, are still active research topics, and we review the state-of-the-art in each of these areas. We also look ahead, identifying unsolved challenges, proposing directions for future research and highlighting the broad range of current and future applications

Assisting Navigation and Object Selection with Vibrotactile Cues

Our lives have been drastically altered by information technology in the last decades, leading to evolutionary mismatches between human traits and the modern environment. One particular mismatch occurs when visually demanding information technology overloads the perceptual, cognitive or motor capabilities of the human nervous system. This information overload could be partly alleviated by complementing visual interaction with haptics. The primary aim of this thesis was to investigate how to assist movement control with vibrotactile cues. Vibrotactile cues refer to technologymediated vibrotactile signals that notify users of perceptual events, propose users to make decisions, and give users feedback from actions. To explore vibrotactile cues, we carried out five experiments in two contexts of movement control: navigation and object selection. The goal was to find ways to reduce information load in these tasks, thus helping users to accomplish the tasks more effectively. We employed measurements such as reaction times, error rates, and task completion times. We also used subjective rating scales, short interviews, and free-form participant comments to assess the vibrotactile assisted interactive systems. The findings of this thesis can be summarized as follows. First, if the context of movement control allows the use of both feedback and feedforward cues, feedback cues are a reasonable first option. Second, when using vibrotactile feedforward cues, using low-level abstractions and supporting the interaction with other modalities can keep the information load as low as possible. Third, the temple area is a feasible actuation location for vibrotactile cues in movement control, including navigation cues and object selection cues with head turns. However, the usability of the area depends on contextual factors such as spatial congruency, the actuation device, and the pace of the interaction task

Summative Stereoscopic Image Compression using Arithmetic Coding

Image compression targets at plummeting the amount of bits required for image representation for save storage space and speed up the transmission over network. The reduction of size helps to store more images in the disk and take less transfer time in the data network. Stereoscopic image refers to a three dimensional (3D) image that is perceived by the human brain as the transformation of two images that is being sent to the left and right human eyes with distinct phases. However, storing of these images takes twice space than a single image and hence the motivation for this novel approach called Summative Stereoscopic Image Compression using Arithmetic Coding (S2ICAC) where the difference and average of these stereo pair images are calculated, quantized in the case of lossy approach and unquantized in the case of lossless approach, and arithmetic coding is applied. The experimental result analysis indicates that the proposed method achieves high compression ratio and high PSNR value. The proposed method is also compared with JPEG 2000 Position Based Coding Scheme(JPEG 2000 PBCS) and Stereoscopic Image Compression using Huffman Coding (SICHC). From the experimental analysis, it is observed that S2ICAC outperforms JPEG 2000 PBCS as well as SICHC

Designing Tomorrow\u27s Reality: The Development and Validation of an Augmented and Mixed Reality Heuristic Checklist

Augmented (AR) and Mixed Reality (MR) are new and currently developing technologies. They have been used and shown promise and popularity in the domains of education, training, enterprise, retail, consumer products, and more. However, there is a lack of consistency and standards in AR and MR devices and applications. Interactions and standards in one application may drastically differ from another. This may make it difficult for users, especially those new to these technologies, to learn and feel comfortable using the devices or applications. It may also hinder the usability of the applications as designers may not follow proven techniques to display this information effectively. One way to create these standards is through the development and acceptance of usability or user experience (UX) heuristics. There is a lack of validated and widely accepted heuristics in AR and MR. Those that do exist tend to be too specialized to be valid across types of applications or devices. This dissertation’s goal is to fill this gap through the creation of a validated usability/user experience (UX) heuristic checklist to evaluate AR or MR devices and/or applications by following a validated methodology for developing usability/user experience heuristics (Quiñones et al., 2018). Previous work had been completed to develop an AR and MR heuristic checklist (Derby & Chaparro, 2022). This work resulted in 11 heuristics and 94 checklist items; however, validation of this checklist was limited. This dissertation broadened the heuristic checklist to ensure applicability to more application types, device types, and use cases. Five different applications and devices were used to validate the checklist through heuristic evaluations and user tests. Experts in the domain also provided their feedback on the heuristic checklist using applications of their choice. A total of 100 revisions were made to the Derby & Chaparro (2022) checklist as a result of this study. The final heuristic checklist consists of 12 heuristics and 109 checklist items that practitioners can use to evaluate AR or MR applications and devices and quantify the results to better inform design

Egocentric Reconstruction of Human Bodies for Real-time Mobile Telepresence

A mobile 3D acquisition system has the potential to make telepresence significantly more convenient, available to users anywhere, anytime, without relying on any instrumented environments. Such a system can be implemented using egocentric reconstruction methods, which rely only on wearable sensors, such as head-worn cameras and body-worn inertial measurement units. Prior egocentric reconstruction methods suffer from incomplete body visibility as well as insufficient sensor data. This dissertation investigates an egocentric 3D capture system relying only on sensors embedded in commonly worn items such as eyeglasses, wristwatches, and shoes. It introduces three advances in egocentric reconstruction of human bodies. (1) A parametric-model-based reconstruction method that overcomes incomplete body surface visibility by estimating the user's body pose and facial expression, and using the results to re-target a high-fidelity pre-scanned model of the user. (2) A learning-based visual-inertial body motion reconstruction system that relies only on eyeglasses-mounted cameras and a few body-worn inertial sensors. This approach overcomes the challenges of self-occlusion and outside-of-camera motions, and allows for unobtrusive real-time 3D capture of the user. (3) A physically plausible reconstruction method based on rigid body dynamics, which reduces motion jitter and prevents interpenetrations between the reconstructed user's model and the objects in the environment such as the ground, walls, and furniture. This dissertation includes experimental results demonstrating the real-time, mobile reconstruction of human bodies in indoor and outdoor scenes, relying only on wearable sensors embedded in commonly-worn objects and overcoming the sparse observation challenges of egocentric reconstruction. The potential usefulness of this approach is demonstrated in a telepresence scenario featuring physical therapy training.Doctor of Philosoph

Simulation-Based Countermeasures Towards Accident Prevention : Virtual Reality Utilization in Industrial Processes and Activities

Despite growing industrial interests in fully immersive virtual reality (VR) applications for safety countermeasures, there is scanty research on the subject in the context of accident prevention during manufacturing processes and plant maintenance activities. This dissertation aims to explore and experiment with VR for accident prevention by targeting three workplace safety countermeasures: fire evacuation drills, hazard identification and risk assessments (HIRA), and emergency preparedness and response (EPR) procedures. Drawing on the virtual reality accident causation model (VR-ACM) (i.e., 3D modelling and simulation, accident causation, and safety drills) and the fire evacuation training model, two industrial 3D simulation models were utilized for the immersive assessment and training. These were a lithium-ion battery (LIB) manufacturing factory and a gas power plant (GPP). In total, five studies (publications) were designed to demonstrate the potential of VR in accident prevention during the manufacturing processes and maintenance activities at the facility conceptual stages. Two studies were with the LIB factory simulation to identify inherent hazards and assess risks for redesigning the factory to ensure workplace safety compliance. The other three studies constituted fire hazard identifications, emergency evacuations and hazard control/mitigations during the maintenance activity in the GPP simulation. Both study models incorporated several participants individually immersed in the virtual realm to experience the accident phenomena intuitively. These participants provided feedback for assessing the research objectives. Results of the studies indicated that several inherent hazards in the LIB factory were identified and controlled/mitigated. Secondly, the GPP experiment results suggested that although the maintenance activity in the virtual realm increased the perception of presence, a statistically significant delay was recorded at the pre-movement stage due to the lack of situational safety awareness. Overall, the study demonstrates that participants immersed in a VR plant maintenance activity and manufacturing factory process simulation environments can experience real-time emergency scenarios and conditions necessary for implementing the essential safety countermeasures to prevent accidents.Vaikka kiinnostus virtuaalitodellisuuden (VR) käyttöön turvallisuuden varotoimissa teollisuudessa on kasvanut, tutkimuksia ei ole juurikaan tehty onnettomuuksien ehkäisystä valmistus- ja kunnossapitotoiminnassa. Tämän väitöskirjan tavoitteena on tutkia ja kokeilla VR:ää tapaturmien ehkäisyssä kohdistuen kolmeen työpaikan turvallisuuden varotoimeen: paloharjoitukset, riskien arvioinnit sekä hätätilanteiden valmiusmenettelyt ja toimintasuunnitelmat (EPR). Kokemuksellisessa ja uppouttavassa koulutuksessa hyödynnettiin kahta teollisuuden 3D-simulointimallia, jotka nojautuvat virtuaalitodellisuuden onnettomuuksien aiheutumismalliin (VR-ACM) (eli 3D-mallinnus- ja simulointi, onnettomuussyy- ja turvallisuuskoulutus) sekä paloharjoitusmalliin. Nämä 3D-simulointimallit ovat litiuminoniakkuja (LIB) valmistava tehdas, joka rakennettiin Visual Components 3D-simulointiohjelmistolla (versio 4.0) ja kaasuvoimala (GPP) Unrealin reaaliaikaisella pelimoottorilla (versio 4.2). Yhteensä viisi tutkimusta (julkaisua) suunniteltiin havainnollistamaan VR:n potentiaalia tapaturmien ehkäisyssä valmistusprosessin layout-suunnittelun ja tehtaan konseptivaiheissa tehtävän kunnossapidon aikana. Kaksi tutkimusta tehtiin LIB-tehdassimulaatiolla vaarojen tunnistamiseksi sekä riskien arvioimiseksi. Tutkimukset tehtiin tehtaan uudelleensuunnittelua varten, työturvallisuuden noudattamisen varmistamiseksi. Muut kolme tutkimusta käsittelevät palovaaran tunnistamista, hätäevakuointia ja riskien vähentämistä huoltotoiminnan aikana GPP-simulaatiossa. Molemmissa tutkimusmalleissa oli useita virtuaalimaailmaan uppoutuneita osallistujia, jotka saivat kokea onnettomuudet yksilöllisesti ja intuitiivisesti. Osallistujat antoivat palautetta kokeen jälkeisessä kyselyssä. Kyselyn tuloksien avulla LIB-tehtaassa tunnistettiin ja lievennettiin useita vaaroja. GPP-kokeilun tulokset viittasivat siihen, että vaikka ylläpitotoiminta virtuaalimaailmassa lisäsi teleläsnäoloa, tilastollisesti merkittävä viive kirjattiin liikettä edeltävässä vaiheessa turvallisuustietoisuuden puuteen vuoksi. Kaiken kaikkiaan tutkimus osoittaa, että VR-laitoksen kunnossapitotoimintaan ja tuotantotehtaan prosessisimulaatioympäristöihin uppoutuvat osallistujat voivat kokea reaaliaikaisia hätäskenaarioita ja olosuhteita, jotka ovat välttämättömiä olennaisten turvallisuustoimien toteuttamiseksi.fi=vertaisarvioitu|en=peerReviewed

New Tech, Old Problem: The Rise of Virtual Rent-to-Own Agreements

This Article explores how fintech has disrupted the traditional rent-to-own (RTO) industry, giving rise to new, virtual RTO agreements (VirTOs). These VirTOs have enabled the RTO industry to expand into the service industry and to markets for products not traditionally associated with rentals, such as vehicle repairs, pet ownership, and medical devices. This Article analyzes this development.RTO agreements purport to rent products to a consumer until the conclusion of a set number of renewable rental payments, at which point ownership transfers. The fundamental characteristic of these agreements – and why they are not regulated as loans – are that the consumer is able to terminate the rental agreement without penalty at any time by returning the merchandise to the rental company. An extremely high-cost form of financing, RTO agreements were traditionally offered through brick-and-mortar stores, like Aaron’s or Rent-A-Center, to low-income, subprime consumers who could not obtain traditional credit. The introduction of fintech, however, has shifted the RTO business model from traditional one-stop shop, brick-and-mortar stores to partnerships between VirTO companies and retailers. As this Article explains, these new VirTOs have different attributes from traditional RTO agreements. In a VirTO, a third-party VirTO provider purchases the desired product from a brick-and-mortar retailer and then rents the product back to the consumer. The entire transaction between the retailer and VirTO company occurs online and unbeknownst to the consumer. This business model, however, has allowed VirTOs to emerge in a variety of specialized markets and services. Not only are these agreements a high-cost method to ownership, but consumers often have little understanding that they are renting their purchases.While VirTOs purport to be rentals, it is nearly impossible for a consumer to return a rental financed with a VirTO. This Article argues that VirTOs are not, in fact, RTO agreements because the items rented with VirTOs are not practical to return. Instead, VirTOs are a sophisticated form of disguised credit. This Article demonstrates that the VirTO industry is a legal fiction designed to avoid consumer protection statutes governing credit. Accordingly, VirTOs should be treated by courts as credit, subject to state usury and federal consumer protection laws. This Article also proposes a series of policy recommendations to regulate VirTOs and to ban such agreements for services and nonsensical products, like vehicle repairs and pets.While this Article focuses solely on VirTOs, its observations about the role of fintech in the RTO industry are instructive for other parts of the fringe economy being disrupted by new technology. The policy solutions proposed in this Article provide a model for potential strategies to protect low-income and subprime consumers from the most extreme abuses as fringe financing industries grapple with the introduction of fintech

Augmented reality for computer assisted orthopaedic surgery

In recent years, computer-assistance and robotics have established their presence in operating theatres and found success in orthopaedic procedures. Benefits of computer assisted orthopaedic surgery (CAOS) have been thoroughly explored in research, finding improvements in clinical outcomes, through increased control and precision over surgical actions. However, human-computer interaction in CAOS remains an evolving field, through emerging display technologies including augmented reality (AR) – a fused view of the real environment with virtual, computer-generated holograms. Interactions between clinicians and patient-specific data generated during CAOS are limited to basic 2D interactions on touchscreen monitors, potentially creating clutter and cognitive challenges in surgery. Work described in this thesis sought to explore the benefits of AR in CAOS through: an integration between commercially available AR and CAOS systems, creating a novel AR-centric surgical workflow to support various tasks of computer-assisted knee arthroplasty, and three pre–clinical studies exploring the impact of the new AR workflow on both existing and newly proposed quantitative and qualitative performance metrics. Early research focused on cloning the (2D) user-interface of an existing CAOS system onto a virtual AR screen and investigating any resulting impacts on usability and performance. An infrared-based registration system is also presented, describing a protocol for calibrating commercial AR headsets with optical trackers, calculating a spatial transformation between surgical and holographic coordinate frames. The main contribution of this thesis is a novel AR workflow designed to support computer-assisted patellofemoral arthroplasty. The reported workflow provided 3D in-situ holographic guidance for CAOS tasks including patient registration, pre-operative planning, and assisted-cutting. Pre-clinical experimental validation on a commercial system (NAVIO®, Smith & Nephew) for these contributions demonstrates encouraging early-stage results showing successful deployment of AR to CAOS systems, and promising indications that AR can enhance the clinician’s interactions in the future. The thesis concludes with a summary of achievements, corresponding limitations and future research opportunities.Open Acces