Wearable AI Systems Group

Dr. Tobias Röddiger

Karlsruhe Institute of Technology (KIT)

Institute of Telematics / TECO

Vincenz-Prießnitz-Straße 1

76131 Karlsruhe, Germany

Building 07.07

Room 206

tobias.roeddigerδkit.edu

Dr. Tobias Röddiger

Profile

I am Tobias Röddiger, a group leader for Wearable Systems at TECO at the Karlsruhe Institute of Technology. In my research I developed intelligent embedded systems at the intersection of hardware, humans, and artificial intelligence. Previously, I studied and conducted research at KIT, MIT, University of Cambridge, and Lancaster University. I have strong ties with industry (e.g., Bosch Sensortec). Additionally, I founded two companies, worked at Microsoft and shipped systems to millions of users.

If you are interested in thesis, HiWi, PhD positions, etc., please send an e-mail!

For a full list of my past experience and publications, please have a look at the resources below.

Teaching

  • Ubiquitous Computing (every fall term)
  • Mobile Computing and Internet of Things - Exercise (every fall term)

Projects

OpenEarable

OpenEarable

OpenEarable is an open-source, AI-enabled platform for ear-based sensing applications with true wireless audio. The modular and reconfigurable platform is packed with a variety of high-precision sensors, designed for both development and research applications.

OpenWearables

OpenWearables

The OpenWearables project is an initiative to advance wearable computing by following open-hardware and open-software principles. It aims to create a research infrastructure and community that makes wearable devices more accessible, extensible, interoperable and impactful.

Overview Excerpt

Affective Wearable Haptic Interventions

This project systematically reviews affective wearable haptic interventions, examining how touch-based wearables regulate emotions and well-being across haptic modalities, body locations, intervention mechanisms, and application contexts.

EarXplore

EarXplore

EarXplore is an evolving, interactive database that organizes and visualizes research on earables. It helps the community explore existing studies, uncover trends, and shape the future of earable technology.

map_em_tsne_trajectory_k16_episode2_1.png

BayaHAR

BayaHAR enables lightweight, gradient-free personalization of pretrained wearable HAR models to new users using only a few seconds of labeled or weakly labeled calibration data, supporting efficient and robust on-device adaptation.

EarStreAM Logo

EarStreAM

EarStreAM is a closed-loop earable system that detects stress through in-ear sensing and automatically delivers personalized, LLM-generated meditation, adapting the intervention until the user’s physiological state returns toward baseline.

KD²School

KD²School

An interdisciplinary graduate school focused on designing adaptive IT systems that improve economic decision-making. The research explores the intersection of human behavior, technology, and institutions.

Finger-to-Ear ECG Pulsewave

Finger-to-Ear ECG

Finger-to-Ear ECG explores earbud-based cardiac monitoring by combining an in-ear electrode with finger contact, enabling high-quality ECG recordings and morphology preservation in a practical wearable form factor.

Calmables

Calmables

Calmables is a closed-loop infrared earable designed to explore thermal biofeedback for relaxation support. The system uses heart-rate data from a smart ring to establish an individual baseline and identify periods of elevated physiological activation. When a personalized threshold is reached, the earable delivers a subtle, localized warming stimulus to the ear using infrared light. A companion smartphone application coordinates the interaction and visualizes physiological changes, while independent temperature limits and communication fail-safes ensure safe operation. In a preliminary placebo-controlled evaluation with 18 participants, the active prototype received higher ratings for perceived relaxation and recovery support than an identical-looking placebo device. Calmables demonstrates how physiological sensing and unobtrusive thermal stimulation can be combined to make biofeedback tangible and support brief moments of recovery.

Heatables

Heatables

Heatables investigates the use of near-infrared (NIR) and infrared (IR) optical stimulation within the human ear to modulate thermal perception and comfort. The project explores the auditory canal as a novel physiological and perceptual interface for personalized thermal regulation.

Publications

2026
Affective Wearable Haptic Interventions: A Systematic Literature Review
Lee, J.; Röddiger, T.; Makarem, S.; Riedel, T.; Kunze, K.; Beigl, M.
2026. Proceedings of the ACM on Interactive, Mobile, Wearable and Ubiquitous Technologies, 10 (1), 1–41. doi:10.1145/3790116 
Reassessing the Feasibility of PPG-Based Non-Invasive Blood Glucose Level Estimation
Ramesh, S.; Neufeld, M.; Küttner, M.; Röddiger, T.; Beigl, M.
2026. ISWC ’26: Proceedings of the 2026 ACM International Symposium on Wearable Computers. Ed.: D. Zhang, 127–133, Association for Computing Machinery (ACM). doi:10.1145/3830727.3834821 
🏆 Best Paper Nominee
Finger-to-Ear ECG: Systematic Evaluation of an Earbud-Based Cardiac Monitoring Approach
Lepold, P.; Breitling, P.; Hummel, J.; Röddiger, T.; Beigl, M.
2026. ISWC ’26: Proceedings of the 2026 ACM International Symposium on Wearable Computers, 71–77, Association for Computing Machinery (ACM). doi:10.1145/3830727.3834819 
2025
WHAR Datasets: An Open Source Library for Wearable Human Activity Recognition
Burzer, M.; King, T.; Riedel, T.; Beigl, M.; Röddiger, T.
2025. Companion of the 2025 ACM International Joint Conference on Pervasive and Ubiquitous Computing, 1315–1322, Association for Computing Machinery (ACM). doi:10.1145/3714394.3756254 Full textFull text of the publication as PDF document 
UltrasonicSpheres: Localized, Multi-Channel Sound Spheres Using Off-the-Shelf Speakers and Earables
Küttner, M.; Zitz, V.; Gerling, K. M.; Beigl, M.; Röddiger, T.
2025. Companion of the 2025 ACM International Joint Conference on Pervasive and Ubiquitous Computing; Espoo, Fannland, 12.-16.10.2025, 439–443, Association for Computing Machinery (ACM). doi:10.1145/3714394.3754416 
Closed-Loop Rhythmic Haptic Biofeedback via Smartwatch for Relaxation and Sleep Onset
Lee, J.; Moschina, D.; Ramesh, S.; Röddiger, T.; Kunze, K.; Beigl, M.
2025. Proceedings of the ACM International Symposium on Wearable Computers (ISWC’25), 30–37, Association for Computing Machinery (ACM). doi:10.1145/3715071.3750412 Full textFull text of the publication as PDF document 
🏆 Best Paper Nominee
Haptic Biofeedback for Wakeful Rest: Does Stimulation Location Make a Difference?
Lee, J.; Filpe, M.; Lepold, P.; Röddiger, T.; Beigl, M.
2025. Proceedings of the 2025 ACM International Symposium on Wearable Computers, 83–90, Association for Computing Machinery (ACM). doi:10.1145/3715071.3750427 Full textFull text of the publication as PDF document 
🏆 Best Paper Award
Heatables: Effects of Infrared-LED-Induced Ear Heating on Thermal Perception, Comfort, and Cognitive Performance
Zitz, V.; Küttner, M.; Hummel, J.; Knierim, M. T.; Beigl, M.; Röddiger, T.
2025. Proceedings of the ACM International Symposium on Wearable Computers (ISWC’25), 91–97, Association for Computing Machinery (ACM). doi:10.1145/3715071.3750421 Full textFull text of the publication as PDF document 
Computing with Smart Rings: A Systematic Literature Review
Wang, Z.; Yu, R.; Wang, X.; Ding, J.; Tang, J.; Fang, J.; He, Z.; Li, Z.; Röddiger, T.; Xu, W.; Zhang, X.; Gao, H.- ang; Gao, N.; Yu, C.; Shi, Y.; Wang, Y.
2025. Proceedings of the ACM on Interactive, Mobile, Wearable and Ubiquitous Technologies, 9 (3), 54 S. doi:10.1145/3749480 Full textFull text of the publication as PDF document 
BodyPursuits: Exploring Smooth Pursuit Gaze Interaction Based on Body Motion Targets
Hansen, A.; Makarem, S.; Kunze, K.; Zhou, Y.; Knierim, M. T.; Clarke, C.; Gellersen, H.; Beigl, M.; Röddiger, T.
2025. Proceedings of the 2025 Symposium on Eye Tracking Research and Applications, Art.-Nr.: 3, Association for Computing Machinery (ACM). doi:10.1145/3715669.3723110 
🏆 Honorable Mention
Demonstrating OpenEarable 2.0: An AI-Powered Ear Sensing Platform
Röddiger, T.; Zitz, V.; Hummel, J.; Küttner, M.; Lepold, P.; King, T.; Paradiso, J. A.; Clarke, C.; Beigl, M.
2025. CHI EA ’25: Proceedings of the Extended Abstracts of the CHI Conference on Human Factors in Computing Systems, Art.-Nr.: 713, Association for Computing Machinery (ACM). doi:10.1145/3706599.3721161 
Fit2Ear Dataset
Zhao, H.; Röddiger, T.; Feng, Y.; Beigl, M.
2025, March 5. doi:10.35097/LuEUQApwxQrvGfKm 
OpenEarable 2.0: Open-Source Earphone Platform for Physiological Ear Sensing
Röddiger, T.; Küttner, M.; Lepold, P.; King, T.; Moschina, D.; Bagge, O.; Paradiso, J. A.; Clarke, C.; Beigl, M.
2025. Proceedings of the ACM on Interactive, Mobile, Wearable and Ubiquitous Technologies, 9 (1), Art.-Nr.: 16. doi:10.1145/3712069 Full textFull text of the publication as PDF document 
Advancing Wearable BCI: Headphone EEG for Cognitive Load Detection in Lab and Field
Knierim, M. T.; Zimny, C.; Ivucic, G.; Röddiger, T.
2025. Proceedings of the ACM on Interactive, Mobile, Wearable and Ubiquitous Technologies, 9 (1), 1–26. doi:10.1145/3712283 
2024
Systematic Comparison of Ear Temperature Probing Positions for Continuous Wearable Vital Sign Monitoring
King, T.; Röddiger, T.; Laubenstein, D.; Beigl, M.
2024. Proceedings of the 2024 ACM International Symposium on Wearable Computers, 144–147, Association for Computing Machinery (ACM). doi:10.1145/3675095.3676627 
OpenEarable ExG: Open-Source Hardware for Ear-Based Biopotential Sensing Applications
Lepold, P.; Röddiger, T.; King, T.; Kunze, K.; Maurer, C.; Beigl, M.
2024. UbiComp ’24: Companion of the 2024 on ACM International Joint Conference on Pervasive and Ubiquitous Computing, 916 – 920, Association for Computing Machinery (ACM). doi:10.1145/3675094.3678480 Full textFull text of the publication as PDF document 
OpenEarable 1.4: Dual Microphones Earpiece to Capture In-Ear and Outer-Ear Audio Signals
Röddiger, T.; Stuchbury-Wass, J.; Ciliberto, M.; Lepold, P.; Beigl, M.
2024. Companion of the 2024 on ACM International Joint Conference on Pervasive and Ubiquitous Computing, 930 – 933, Association for Computing Machinery (ACM). doi:10.1145/3675094.3678483 
Fit2Ear: Generating Personalized Earplugs from Smartphone Depth Camera Images
Zhao, H.; Röddiger, T.; Yufei, F.; Beigl, M.
2024. ACM International Joint Conference on Pervasive and Ubiquitous Computing (UbiComp ’24), 679 – 684, Association for Computing Machinery (ACM). doi:10.1145/3675094.3680525 
AutoAugHAR: Automated Data Augmentation for Sensor-based Human Activity Recognition
Zhou, Y.; Zhao, H.; Huang, Y.; Röddiger, T.; Kurnaz, M.; Riedel, T.; Beigl, M.
2024. Proceedings of the ACM on Interactive, Mobile, Wearable and Ubiquitous Technologies, 8 (2), Art.-Nr.: 48. doi:10.1145/3659589 Full textFull text of the publication as PDF document 
Enhancing Efficiency in HAR Models: NAS Meets Pruning
Zhou, Y.; King, T.; Huang, Y.; Zhao, H.; Riedel, T.; Röddiger, T.; Beigl, M.
2024. 22nd IEEE International Conference on Pervasive Computing and Communications (PerCom 2024), 33–38, Institute of Electrical and Electronics Engineers (IEEE). doi:10.1109/PerComWorkshops59983.2024.10502894 Full textFull text of the publication as PDF document 
PictographAI: Interactive Generation of Stylized Pictographs for Presentations
Makarem, S.; Röddiger, T.; Riedel, T.; Beigl, M.
2024. Mensch und Computer 2024 - Workshopband : 01.-04. September 2024, Karlsruhe, Germany, Gesellschaft für Informatik (GI). doi:10.18420/muc2024-mci-demo-305 
SciEx: Benchmarking Large Language Models on Scientific Exams with Human Expert Grading and Automatic Grading
Dinh, T. A.; Mullov, C.; Bärmann, L.; Li, Z.; Liu, D.; Reiß, S.; Lee, J.; Lerzer, N.; Ternava, F.; Gao, J.; Röddiger, T.; Waibel, A.; Asfour, T.; Beigl, M.; Stiefelhagen, R.; Dachsbacher, C.; Böhm, K.; Niehues, J.
2024. arxiv. doi:10.48550/arXiv.2406.10421 Full textFull text of the publication as PDF document 
SciEx: Benchmarking Large Language Models on Scientific Exams with Human Expert Grading and Automatic Grading
Dinh, T. A.; Mullov, C.; Bärmann, L.; Li, Z.; Liu, D.; Reiß, S.; Lee, J.; Lerzer, N.; Gao, J.; Peller-Konrad, F.; Röddiger, T.; Waibel, A.; Asfour, T.; Beigl, M.; Stiefelhagen, R.; Dachsbacher, C.; Böhm, K.; Niehues, J.
2024. Y. Al-Onaizan, M. Bansal & Y.-N. Chen (Eds.), Proceedings of the 2024 Conference on Empirical Methods in Natural Language Processing, Miami, 12th-16th November 2024, Hrsg.: Al-Onaizan, Y., Bansal, M., Chen, Y.-N., 11592–11610, Association for Computational Linguistics (ACL). doi:10.18653/v1/2024.emnlp-main.647 Full textFull text of the publication as PDF document 
2023
Vertical Jump Test Using an Earable Accelerometer
Moschina, D.; Röddiger, T.; Beigl, M.
2023. UbiComp/ISWC ’23 Adjunct: Adjunct Proceedings of the 2023 ACM International Joint Conference on Pervasive and Ubiquitous Computing & the 2023 ACM International Symposium on Wearable Computing, Ed.: M. Tentori, 324 – 326, Association for Computing Machinery (ACM). doi:10.1145/3594739.3610669 
OpenEarable: Open Hardware Earable Sensing Platform
Röddiger, T.; King, T.; Roodt, D. R.; Clarke, C.; Beigl, M.
2023. UbiComp/ISWC ’22 Adjunct: Adjunct Proceedings of the 2022 ACM International Joint Conference on Pervasive and Ubiquitous Computing and the 2022 ACM International Symposium on Wearable Computers, 246–251, Association for Computing Machinery (ACM). doi:10.1145/3544793.3563415 
OpenBCI + 3D-Printed Headphones = Open ExG Headphones – An Open-Source Research Platform for Biopotential Earable Applications
Knierim, M. T.; Puhl, D.; Ivucic, G.; Röddiger, T.
2023. CHI EA ’23: Extended Abstracts of the 2023 CHI Conference on Human Factors in Computing Systems. Ed.: A. Schmidt, Art.-Nr.: 221, Association for Computing Machinery (ACM). doi:10.1145/3544549.3585875 
2022
Tools and methods for Edge-AI-systems
Schwabe, N.; Zhou, Y.; Hielscher, L.; Röddiger, T.; Riedel, T.; Reiter, S.
2022. at - Automatisierungstechnik, 70 (9), 767–776. doi:10.1515/auto-2022-0023 
OpenEarable: Open Hardware Earable Sensing Platform
Röddiger, T.; King, T.; Roodt, D. R.; Clarke, C.; Beigl, M.
2022, September 15 
Towards Detecting Complete Chest Recoil from Smartphone Vibration Strength during Cardiopulmonary Resuscitation
Hermann, S.; Röddiger, T.; Beigl, M.
2022. Proceedings of the 2022 ACM International Symposium on Wearable Computers, 103–105, Association for Computing Machinery (ACM). doi:10.1145/3544794.3558472 
Sensing with Earables: A Systematic Literature Review and Taxonomy of Phenomena
Röddiger, T.; Clarke, C.; Breitling, P.; Schneegans, T.; Zhao, H.; Gellersen, H.; Beigl, M.
2022. Proceedings of the ACM on Interactive, Mobile, Wearable and Ubiquitous Technologies, 6 (3), Article 135. doi:10.1145/3550314 Full textFull text of the publication as PDF document 
2021
Earrumble: Discreet hands-and eyes-free input by voluntary tensor tympani muscle contraction
Röddiger, T.; Clarke, C.; Wolffram, D.; Budde, M.; Beigl, M.
2021. Proceedings of the 2021 CHI Conference on Human Factors in Computing Systems, Art.-Nr.: 743, Association for Computing Machinery (ACM). doi:10.1145/3411764.3445205 Full textFull text of the publication as PDF document 
EarRecorder: A Multi-Device Earable Data Collection Toolkit
Fang, L.; Röddiger, T.; Schmid, F.; Beigl, M.
2021. Augmented Humans Conference 2021, 286–288, Association for Computing Machinery (ACM). doi:10.1145/3458709.3459005 
AirCase: Earable Charging Case with Air Quality Monitoring and Soundscape Sonification
Zhao, H.; Roddiger, T.; Beigl, M.
2021. Proceedings of the 2021 ACM International Joint Conference on Pervasive and Ubiquitous Computing and Proceedings of the 2021 ACM International Symposium on Wearable Computers: September 21-25, 2021 ; Virtual Event, 180–184, Association for Computing Machinery (ACM). doi:10.1145/3460418.3479329 
2020
🏆 Best Paper Award
FLECTILE: 3D-printable soft actuators for wearable computing
Fang, L.; Röddiger, T.; Sun, H.; Willenbacher, N.; Beigl, M.
2020. UbiComp/ISWC ’20: 2020 ACM International Joint Conference on Pervasive and Ubiquitous Computing and 2020 ACM International Symposium on Wearable Computers. Ed.: K. v. Laerhoven, 32–36, Association for Computing Machinery (ACM). doi:10.1145/3410531.3414307 Full textFull text of the publication as PDF document 
Design Space and Usability of Earable Prototyping
Röddiger, T.; Beigl, M.; Exler, A.
2020. UbiComp/ISWC ’20: 2020 ACM International Joint Conference on Pervasive and Ubiquitous Computing and 2020 ACM International Symposium on Wearable Computers, Virtual Event, Mexico, September, 2020. Ed.: K. van Laerhoven, 73–78, Association for Computing Machinery (ACM). doi:10.1145/3410531.3414302 Full textFull text of the publication as PDF document 
PDMSkin – On-Skin Gestures with Printable Ultra-Stretchable Soft Electronic Second Skin
Röddiger, T.; Beigl, M.; Wolffram, D.; Budde, M.; Sun, H.
2020. AHs ’20: Proceedings of the Augmented Humans International Conference, March 2020, Article No.: 28, Association for Computing Machinery (ACM). doi:10.1145/3384657.3384789 Full textFull text of the publication as PDF document 
Wearability and Comfort of Earables during Sleep
Röddiger, T.; Dinse, C.; Beigl, M.
2020. ISWC’21: Proceedings of the 2021 ACM International Symposium on Wearable Computers: September 21-26, 2021 ; Virtual Event, 150–152, Association for Computing Machinery (ACM). doi:10.1145/3460421.3480432 
Where Should i Look? Comparing Reference Frames for Spatial Tactile Cues
Pescara, E.; Stubenbord, A.; Röddiger, T.; Fang, L.; Beigl, M.
2020. ISWC’21: Proceedings of the 2021 ACM International Symposium on Wearable Computers: September 21-26, 2021 ; Virtual Event, 68–72, Association for Computing Machinery (ACM). doi:10.1145/3460421.3478822 
Cardiopulmonary Resuscitation Support: Comparison of Wrist-, Chest-, and Ear-Worn Devices and Estimation Algorithms
Hermann, S.; Breitling, P.; Röddiger, T.; Beigl, M.
2020. ISWC’21: Proceedings of the 2021 ACM International Symposium on Wearable Computers: September 21-26, 2021 ; Virtual Event, 28–32, Association for Computing Machinery (ACM). doi:10.1145/3460421.3478820 
2019
🏆 Best Paper Award
Towards Respiration Rate Monitoring Using an In-Ear Headphone Inertial Measurement Unit
Röddiger, T.; Wolffram, D.; Laubenstein, D.; Budde, M.; Beigl, M.
2019. UbiComp ’19: The 2019 ACM International Joint Conference on Pervasive and Ubiquitous Computing - EarComp’19: Proceedings of the 1st International Workshop on Earable Computing - London, United Kingdom, 9th-13th September 2019, 48–53, Association for Computing Machinery (ACM). doi:10.1145/3345615.3361130 Full textFull text of the publication as PDF document 
2018
ARMart – AR-Based Shopping Assistant to Choose and Find Store Items
Röddiger, T.; Doerner, D.; Beigl, M.
2018. 2018 Joint ACM International Conference on Pervasive and Ubiquitous Computing, UbiComp 2018 and 2018 ACM International Symposium on Wearable Computers, ISWC 2018; Singapore; Singapore; 8 October 2018 through 12 October 2018, 440–443, Association for Computing Machinery (ACM). doi:10.1145/3267305.3267631 Full textFull text of the publication as PDF document 
VOCNEA: Sleep apnea and hypopnea detection using a novel tiny gas sensor
Röddiger, T.; Beigl, M.; Köpke, M.; Budde, M.
2018. 22nd International Symposium on Wearable Computers, ISWC 2018; Singapore; Singapore; 8 October 2018 through 12 October 2018, 226–227, Association for Computing Machinery (ACM). doi:10.1145/3267242.3267273 Full textFull text of the publication as PDF document