Research

2025

RF4XR
Radiance Fields in XR: A Survey on How Radiance Fields are Envisioned and Addressed for XR Research
2025 IEEE Transaction on Visualization and Computer Graphics (TVCG) (to appear at ISMAR 25)
Paper (arxiv preprint)/ Awesome RF4XR Repo/ Project Page
This survey paper aims to answer the following questions: i). how RF is envisioned for XR applications, (ii) how they have already been implemented, and (iii) the remaining research gaps through a systematic survey of radiance fields for XR of 365 papers.

I Hear, See, Speak & Do Demo
A Conversational Virtual Agent with Physics-based Interactive Behaviour
Joan Llobera, Ke Li, Pierre Nagorny, Caecilia Charbonnier Frank Steinicke
2025 IEEE International Symposium on Mixed and Augmented Reality (ISMAR)
Paper coming soon.../ Video demo coming soon...
A technical demo showcasing the first embodied anthropomorphic intelligent virtual agent that can react to real-time physics-based events in standalone immersive VR experiences. (A collaboration with the [ARTANIM foundation](https://artanim.ch/))

I Hear, See, Speak & Do Demo
I Hear, See, Speak & Do: Bringing Multimodal Information Processing to Intelligent Virtual Agents for Natural Human-AI Communication
Ke Li*, Fariba Mostajeran*, Sebastian Rings, Lucie Kruse, Susanne Schmidt, Michael Arz, Erik Wolf, Frank Steinicke
2025 IEEE Conference on Virtual Reality and 3D User Interfaces Abstracts and Workshops (VRW 2025)
Paper/ Code coming soon/ Video
This technical demo explores multimodal information processing techniques (e.g.facial expression, body actions) to enable intelligent virtual agents for natural human–AI communication in immersive extended reality environments.

nuance
Effects of Verbal Interruption in Conversations with an Intelligent Virtual Agent in Virtual Reality
David Egelhofer, Jiafan Gao, Nils Heinsohn, Sherwin Khabari, Lucie Kruse, Ke Li, Fariba Mostajeran, Frank Steinicke
Conditionally accepted at ACM Symposium on Spatial User Interface (SUI) 2025
Paper (coming soon..)
This is a student lead paper investigating the effects of granularity of being able to interrupt an intelligent virtual agent during a conversation in VR.

nuance
Nuance in Non-Verbal Communication: How Emotional Granularity Impacts Perception of Intelligent Virtual Agents in Virtual Reality
Ayko Schwedler, Celestina Hermida da Costa, Leon Korkmaz, Rateb Karanzie, Lucie Kruse, Ke Li, Fariba Mostajeran, Frank Steinicke
Universal Augmented Interaction Workshop (UNAI) at the IEEE International Symposium on Mixed and Augmented Reality (ISMAR) 2025
Paper (coming soon..)
This is a student lead paper investigating the effects of granularity of IVA's emotional expression on user perception when interacting with IVA in VR.

ieeevr25workshopteaser
A Toolkit for Creating Intelligent Virtual Humans in Extended Reality
Fariba Mostajeran*, Ke Li*, Sebastian Rings, Lucie Kruse, Erik Wolf, , Susanne Schmidt, , Michael Arz, , Joan Llobera, , Pierre Nagorny, , Caecilia Charbonnier, , Hannes Fassold, , Xenxo Alvarez, , André Tavarest, , Nuno Santos, , João Orvalho, , Sergi Fernández, , Frank Steinicke
2025 IEEE Conference on Virtual Reality and 3D User Interfaces Abstracts and Workshops (VRW)
Paper/ Code coming soon..
This workshop paper presents the entire technical stack of the Intelligent Virtual Human technology developed within the EU project PRESENCE , including virtul human creation, real-time action recognition, physics based animation, and speech and facial interactions.

2024

MR Tunneling Demo
Towards a Particle Accelerator Metaverse: Mixed Reality Interfaces for Operations of Complex Physics Facilities
Ke Li, Reinhard Bacher (Supervisor), Wim Leemans (Supervisor) , Frank Steinicke (Supervisor)
PhD Dissertation
As a first step towards a particle accelerator metaverse, this dissertation explored how MR can be used to improve workflows for users working in extreme, complex, and hazardous conditions such as high-energy laser facilities and particle accelerator tunnels while contributing to the advancement of MR technology in general.

MR Tunneling Demo
Reality Fusion: Robust Real-time Immersive Mobile Robot Teleoperation with Volumetric Visual Data Fusion
Ke Li, Reinhard Bacher, Susanne Schmidt, Wim Leemans, Frank Steinicke
2024 IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS 2024, oral presentation)
Paper/ Code/ Video
A high performance and robust immersive robot teleoperation system that combines the best of both worlds: the high fidelity of neural rendering (3D Gaussian Splattings) and real-time stereoscopic point cloud projection.

MR Tunneling Demo
Magic NeRF Lens: Interactive Fusion of Neural Radiance Field for Virtual Facility Inspections
Frontiers in Virtual Reality
Ke Li, Susanne Schmidt, Tim Rolff, Reinhard Bacher, Wim Leemans, Frank Steinicke
Paper/ Code/ News / Video
Virtual inspection and maintenance of particle accelerators by combining CAD models and NeRF models through different magic lens effects.

2023

MR Tunneling Demo
VRS-NeRF:Accelerating Neural Radiance Field Rendering with Variable Rate Shading
Tim Rolff, Susanne Schmidt, Ke Li, Frank Steinicke, Simone Frintrop
2023 IEEE International Symposium on Mixed and Augmented Reality (ISMAR)
Paper
Lightning-fast VR-NeRF rendering with variable rate shading (VRS) utilizing characteristics of human vision (e.g. visual saliency, gaze, edges).

MR Tunneling Demo
RealityGit: Cross Reality Version Control of R&D Optical Workbench
Ke Li, Tim Rolff, Reinhard Bacher, Frank Steinicke
Honorable Mention for Best Design at ISMAR 2023 Student Competition
Video Demo / Paper
Exploring ideas of using NeRF to support multi-user collaborations across the spatial-temporal realities.

MR Tunneling Demo
Immersive Neural Graphics Primitives
Ke Li*, Tim Rolff*, Susanne Schmidt, Reinhard Bacher, Simone Frintrop, Wim Leemans, Frank Steinicke
*Equal contributions.
IEEE Conference on Virtual Reality and 3D User Interfaces (IEEE VR) 2023
Arxiv / Code/ Video
The first open-source VR NERF Unity package that brings high resolution, low-latency, 6-DOF NeRF rendering to VR based on Nvidia's instant-ngp.

2022

MR Tunneling Demo
Mixed Reality Tunneling Effects for Stereoscopic Untethered Video-See-Through Head-Mounted Displays
Ke Li, Susanne Schmidt, Reinhard Bacher, Wim Leemans, Frank Steinicke
2022 IEEE International Symposium on Mixed and Augmented Reality (ISMAR)
Paper / Code / Video
A novel sensor fusion technique that merges VST streams with various latency and resolution and leverages human's perceptual characteristics.
MR Tunneling Demo
Stereoscopic Video See-Through Head-Mounted Displays for Laser Safety: An Empirical Evaluation at Advanced Optics Laboratories
Ke Li, Aradhana Choudhuri, Susanne Schmidt, Tino Lang, Ingmar Hartl, Wim Leemans, Frank Steinicke
2022 IEEE International Symposium on Mixed and Augmented Reality (ISMAR)
Paper / Video
The first work of using a stereoscopic VST-HMD as laser safety goggles with evaluation by 14 laser experts at DESY.
MR Tunneling Demo
Taming Cyclops: Mixed Reality Head-Mounted Displays as Laser Safety Goggles for Advanced Optics Laboratories
Ke Li, Aradhana Choudhuri, Susanne Schmidt, Ingmar Hartl, Wim Leemans, Frank Steinicke
2022 IEEE Conference on Virtual Reality and 3D User Interfaces (IEEE VR) / Poster
A novel application of using mixed reality for eye protection for high power laser laboratories.
cozmo demo
Towards Robust Exocentric Mobile Robot Tele-Operation in Mixed Reality
Ke Li, Reinhard Bacher, Wim Leemans, Frank Steinicke
5th International Workshop on Virtual, Augmented, and Mixed Reality for HRI. (VAM-HRI)
Paper / Project / Code
MR Tunneling Demo
Single Shot Phase Shift 3D Scanning with Convolutional Neural Network and Synthetic Fractals
Ke Li, Spehr, Marcel, Höhne, Daniel, Bräuer-Burchardt, Christian, Tünnermann, Andreas , Kühmstedt, Peter
2022 Eurographics Symposium on 3D Object Retrieval / Paper
My master thesis work at the Fraunhofer IOF.