arXiv subjects

Markus Tatzgern

Publications and source records attributed to Markus Tatzgern.

5 recordsLinked to original sources

arXiv2026

Conceptualising an Initial Design Space for Guidance in Digital Physical Activity Support

Providing guidance is frequently referenced as a key capability of digital health interventions targeting physical activity, yet the term remains poorly defined and inconsistently applied. Existing work often conflates guidance with related constructs such as personalisation, feedback, or persuasion, limiting both theoretical clarity and design progress. This paper conceptualises an initial design space of guidance in the context of digital physical activity support. We define guidance for physical activity as situated, action-oriented support that scaffolds users' embodied engagement in physical activity. Drawing on literature from behaviour change, human-computer interaction, embodied cognition, and digital health, we outline a design space that characterises guidance along multiple dimensions: scope, purpose, timing, context, modality, embodiment, adaptivity, autonomy, and affective quality. By offering a structured vocabulary and conceptual foundation, this work aims to support more coherent research, comparisons, and responsible design of digital health interventions featuring guidance for physical activity support.

cs.HC↗

arXiv2026

Where's the Team Spirit? An Exploratory Study on Team Development Through Co-located Tablet-Based VR

We explore how narrative-driven asymmetric VR experiences can support the development of teamwork-related knowledge, skills, and attitudes (KSAs), such as communication, coordination, trust, and reflexivity. We present the design and evaluation of a tablet-based VR training experience structured around spatial separation, tool asymmetry, and interdependent tasks that require verbal coordination. The experience was designed based on interviews with HR professionals and mapped to a framework of established KSAs. We conducted a co-located user study (N=16) that involved two consecutive collaborative scenarios. Our findings show that users adapted dynamically using verbal exchange, role negotiation, and shared representations to coordinate under asymmetric conditions. We also observed active application of teamwork KSAs. Based on our insights, we present design recommendations for creating effective immersive team training interventions.

cs.HC↗

arXiv2025

See What I Mean? Mobile Eye-Perspective Rendering for Optical See-through Head-mounted Displays

Image-based scene understanding allows Augmented Reality systems to provide contextual visual guidance in unprepared, real-world environments. While effective on video see-through (VST) head-mounted displays (HMDs), such methods suffer on optical see-through (OST) HMDs due to misregistration between the world-facing camera and the user's eye perspective. To approximate the user's true eye view, we implement and evaluate three software-based eye-perspective rendering (EPR) techniques on a commercially available, untethered OST HMD (Microsoft HoloLens 2): (1) Plane-Proxy EPR, projecting onto a fixed-distance plane; (2) Mesh-Proxy EPR, using SLAM-based reconstruction for projection; and (3) Gaze-Proxy EPR, a novel eye-tracking-based method that aligns the projection with the user's gaze depth. A user study on real-world tasks underscores the importance of accurate EPR and demonstrates gaze-proxy as a lightweight alternative to geometry-based methods. We release our EPR framework as open source.

cs.HC↗

arXiv2024

XR Prototyping of Mixed Reality Visualizations: Compensating Interaction Latency for a Medical Imaging Robot

Researching novel user experiences in medicine is challenging due to limited access to equipment and strict ethical protocols. Extended Reality (XR) simulation technologies offer a cost- and time-efficient solution for developing interactive systems. Recent work has shown Extended Reality Prototyping (XRP)'s potential, but its applicability to specific domains like controlling complex machinery needs further exploration. This paper explores the benefits and limitations of XRP in controlling a mobile medical imaging robot. We compare two XR visualization techniques to reduce perceived latency between user input and robot activation. Our XRP validation study demonstrates its potential for comparative studies, but identifies a gap in modeling human behavior in the analytic XRP validation framework.

cs.HC↗

arXiv2017

Adaptive User Perspective Rendering for Handheld Augmented Reality

Handheld Augmented Reality commonly implements some variant of magic lens rendering, which turns only a fraction of the user's real environment into AR while the rest of the environment remains unaffected. Since handheld AR devices are commonly equipped with video see-through capabilities, AR magic lens applications often suffer from spatial distortions, because the AR environment is presented from the perspective of the camera of the mobile device. Recent approaches counteract this distortion based on estimations of the user's head position, rendering the scene from the user's perspective. To this end, approaches usually apply face-tracking algorithms on the front camera of the mobile device. However, this demands high computational resources and therefore commonly affects the performance of the application beyond the already high computational load of AR applications. In this paper, we present a method to reduce the computational demands for user perspective rendering by applying lightweight optical flow tracking and an estimation of the user's motion before head tracking is started. We demonstrate the suitability of our approach for computationally limited mobile devices and we compare it to device perspective rendering, to head tracked user perspective rendering, as well as to fixed point of view user perspective rendering.

cs.HC↗