UX Engineer | HCI Researcher
Daniel Groeger

About me

Hi, I’m a UX Engineer based in the Frankfurt am Main, Germany. Previously I was a researcher of interactive technologies at the intersection of Human-Computer Interaction (HCI), hardware and software engineering, and material science.

My research is about novel ways to interact with digital technologies embodied in our physical world. It focuses on interfaces that merge with real-world objects to leverage their diverse geometry and materiality for interaction. In my work, I have presented several novel digital design and fabrication approaches for customized interactive objects.

In the past, I have worked on Computer Vision and Machine Learning, e.g. for automotive user interfaces.

LASEC

Instant Fabrication of Stretchable Circuits Using a Laser Cutter

We introduce LASEC, the first technique for instant do-it-yourself fabrication of circuits with custom stretchability on a conventional laser cutter and in a single pass. The approach is based on integrated cutting and ablation of a two-layer material using parametric design patterns.

Abstract

Stretchable interfaces are becoming increasingly relevant in interaction design. Thus far, however, we lack a technique for instantly fabricating stretchable interface prototypes. This paper introduces LASEC, the first technique for instant do-it-yourself fabrication of circuits with custom stretchability on a conventional laser cutter and in a single pass. The approach is based on integrated cutting and ablation of a two-layer material using parametric design patterns. These patterns enable the designer to customize the desired stretchability of the circuit, to combine stretchable with non-stretchable areas, or to integrate areas of different stretchability. For adding circuits on such stretchable cut patterns, we contribute routing strategies and a real-time routing algorithm. An interactive design tool assists designers by automatically generating patterns and circuits from a high-level specification of the desired interface. The approach is compatible with off-the-shelf materials and can realize transparent interfaces. Several application examples demonstrate the versatility of the novel technique for applications in wearable computing, interactive textiles, and stretchable input devices.

Video

Publication

Daniel Groeger and Jürgen Steimle
LASEC: Instant Fabrication of Stretchable Circuits Using a Laser Cutter
In Proceedings of the SIGCHI Conference on Human Factors in Computing Systems (CHI ’19).

@inproceedings{Groeger:2019:LIF:3290605.3300929,
author = {Groeger, Daniel and Steimle, J"{u}rgen},
title = {LASEC: Instant Fabrication of Stretchable Circuits Using a Laser Cutter},
booktitle = {Proceedings of the 2019 CHI Conference on Human Factors in Computing Systems},
series = {CHI '19},
year = {2019},
isbn = {978-1-4503-5970-2},
location = {Glasgow, Scotland Uk},
pages = {699:1--699:14},
articleno = {699},
numpages = {14},
url = {http://doi.acm.org/10.1145/3290605.3300929},
doi = {10.1145/3290605.3300929},
acmid = {3300929},
publisher = {ACM},
address = {New York, NY, USA},
keywords = {fabrication, laser ablation, laser cutting, rapid prototyping, stretchable circuits},
}

Tactlets

Adding Tactile Feedback to 3D Objects Using Custom Printed Controls

We present a novel digital fabrication approach for printing custom, high-resolution controls for electro-tactile output with integrated touch sensing on interactive objects. We contribute a design tool for modeling, testing, and refining tactile input and output at a high level of abstraction and an inventory of 10 parametric Tactlet controls that integrate sensing of user input with real-time electro-tactile feedback.

Abstract

Rapid prototyping of haptic output on 3D objects promises to enable a more widespread use of the tactile channel for ubiquitous, tangible, and wearable computing. Existing prototyping approaches, however, have limited tactile output capabilities, require advanced skills for design and fabrication, or are incompatible with curved object geometries. In this paper, we present a novel digital fabrication approach for printing custom, high-resolution controls for electro-tactile output with integrated touch sensing on interactive objects. It supports curved geometries of everyday objects. We contribute a design tool for modeling, testing, and refining tactile input and output at a high level of abstraction, based on parameterized electro-tactile controls. We further contribute an inventory of 10 parametric Tactlet controls that integrate sensing of user input with real-time electro-tactile feedback. We present two approaches for printing Tactlets on 3D objects, using conductive inkjet printing or FDM 3D-printing. Empirical results from a psychophysical study and findings from two practical application cases confirm the functionality and practical feasibility of the Tactlets approach.

Video

Publication

Daniel Groeger, Martin Feick, Anusha Withana, and Jürgen Steimle
Tactlets: Adding Tactile Feedback to 3D Objects Using Custom Printed Controls
In Proceedings of the annual ACM symposium on User interface software and technology (UIST) 2019. (to appear)

@inproceedings{10.1145/3332165.3347937,
author = {Groeger, Daniel and Feick, Martin and Withana, Anusha and Steimle, J\"{u}rgen},
title = {Tactlets: Adding Tactile Feedback to 3D Objects Using Custom Printed Controls},
year = {2019},
isbn = {9781450368162},
publisher = {Association for Computing Machinery},
address = {New York, NY, USA},
url = {https://doi.org/10.1145/3332165.3347937},
doi = {10.1145/3332165.3347937},
abstract = {Rapid prototyping of haptic output on 3D objects promises to enable a more widespread
use of the tactile channel for ubiquitous, tangible, and wearable computing. Existing
prototyping approaches, however, have limited tactile output capabilities, require
advanced skills for design and fabrication, or are incompatible with curved object
geometries. In this paper, we present a novel digital fabrication approach for printing
custom, high-resolution controls for electro-tactile output with integrated touch
sensing on interactive objects. It supports curved geometries of everyday objects.
We contribute a design tool for modeling, testing, and refining tactile input and
output at a high level of abstraction, based on parameterized electro-tactile controls.
We further contribute an inventory of 10 parametric Tactlet controls that integrate
sensing of user input with real-time electro-tactile feedback. We present two approaches
for printing Tactlets on 3D objects, using conductive inkjet printing or FDM 3D printing.
Empirical results from a psychophysical study and findings from two practical application
cases confirm the functionality and practical feasibility of the Tactlets approach.},
booktitle = {Proceedings of the 32nd Annual ACM Symposium on User Interface Software and Technology},
pages = {923–936},
numpages = {14},
keywords = {tactile output, haptics, fabrication, rapid prototyping},
location = {New Orleans, LA, USA},
series = {UIST '19}
}
                    
                        

HotFlex

Post-print Customization of 3D Prints Using Embedded State Change

We propose HotFlex: a new approach allowing precisely located parts of a 3D object to transition on demand from a solid into a deformable state and back. This approach enables intuitive hands-on remodeling, personalization, and customization of a 3D object after it is printed.

Abstract

While 3D printing offers great design flexibility before the object is printed, it is very hard for end-users to customize a 3D-printed object to their specific needs after it is printed. We propose HotFlex: a new approach allowing precisely located parts of a 3D object to transition on demand from a solid into a deformable state and back. This approach enables intuitive hands-on remodeling, personalization, and customization of a 3D object after it is printed. We introduce the approach and present an implementation based on computer-controlled printed heating elements that are embedded within the 3D object. We present a set of functional patterns that act as building blocks and enable various forms of hands-on customization. Furthermore, we demonstrate how to integrate sensing of user input and visual output. A series of technical experiments and various application examples demonstrate the practical feasibility of the approach.

Video

Publication

Daniel Groeger, Elena Chong Loo, and Jürgen Steimle
HotFlex: Post-print Customization of 3D Prints Using Embedded State Change
In Proceedings of the SIGCHI Conference on Human Factors in Computing Systems (CHI ’16).
Best Paper Honorable Mention

@inproceedings{Groeger:2016:HPC:2858036.2858191,
author = {Groeger, Daniel and Chong Loo, Elena and Steimle, J"{u}rgen},
title = {HotFlex: Post-print Customization of 3D Prints Using Embedded State Change},
booktitle = {Proceedings of the 2016 CHI Conference on Human Factors in Computing Systems},
series = {CHI '16},
year = {2016},
isbn = {978-1-4503-3362-7},
location = {San Jose, California, USA},
pages = {420--432},
numpages = {13},
url = {http://doi.acm.org/10.1145/2858036.2858191},
doi = {10.1145/2858036.2858191},
acmid = {2858191},
publisher = {ACM},
address = {New York, NY, USA},
keywords = {3d modeling, 3d printing, fabrication, printed electronics., prototyping, shape change, tangible interaction},
}

Tacttoo

A Thin and Feel-Through Tattoo for On-Skin Tactile Output

This paper introduces Tacttoo, a feel-through interface for electro-tactile output on the user's skin. Our results show that Tacttoo retains the natural tactile acuity similar to bare skin while delivering high-density tactile output.

Abstract

This paper introduces Tacttoo, a feel-through interface for electro-tactile output on the user's skin. Integrated in a temporary tattoo with a thin and conformal form factor, it can be applied on complex body geometries, including the fingertip, and is scalable to various body locations. At less than 35µm in thickness, it is the thinnest tactile interface for wearable computing to date. Our results show that Tacttoo retains the natural tactile acuity similar to bare skin while delivering high-density tactile output. We present the fabrication of customized Tacttoo tattoos using DIY tools and contribute a mechanism for consistent electro-tactile operation on the skin. Moreover, we explore new interactive scenarios that are enabled by Tacttoo. Applications in tactile augmented reality and on-skin interaction benefit from a seamless augmentation of real-world tactile cues with computer-generated stimuli. Applications in virtual reality and private notifications benefit from high-density output in an ergonomic form factor. Results from two psychophysical studies and a technical evaluation demonstrate Tacttoo's functionality, feel-through properties and durability.

Video

Publication

Anusha Withana, Daniel Groeger, and Jürgen Steimle
Tacttoo: A Thin and Feel-Through Tattoo for On-Skin Tactile Output
In Proceedings of the annual ACM symposium on User interface software and technology (UIST) 2018.

 @inproceedings{Withana:2018:TTF:3242587.3242645,
author = {Withana, Anusha and Groeger, Daniel and Steimle, J"{u}rgen},
title = {Tacttoo: A Thin and Feel-Through Tattoo for On-Skin Tactile Output},
booktitle = {Proceedings of the 31st Annual ACM Symposium on User Interface Software and Technology},
series = {UIST '18},
year = {2018},
isbn = {978-1-4503-5948-1},
location = {Berlin, Germany},
pages = {365--378},
numpages = {14},
url = {http://doi.acm.org/10.1145/3242587.3242645},
doi = {10.1145/3242587.3242645},
acmid = {3242645},
publisher = {ACM},
address = {New York, NY, USA},
keywords = {electro-tactile, fabrication, on-body interaction, printed electronics, skin, tactile display, tattoo, wearable computing},
}

ObjectSkin

Augmenting Everyday Objects with Hydroprinted Touch Sensors and Displays

This paper presents a novel a fabrication technique for adding conformal interactive surfaces to rigid and flexible everyday objects.

Abstract

Augmenting everyday objects with interactive input and output surfaces is a long-standing topic in ubiquitous computing and HCI research. Existing approaches, however, fail to leverage the objects’ full potential, particularly in highly curved organic geometries and in diverse visuo-haptic surface properties. We contribute ObjectSkin, a fabrication technique for adding conformal interactive surfaces to rigid and flexible everyday objects. It enables multi-touch sensing and display output that seamlessly integrates with highly curved and irregular geometries. The approach is based on a novel water-transfer process for interactive surfaces. It leverages off-the-shelf hobbyist equipment to fabricate thin, conformal, and translucent electronic circuits that preserve the surface characteristics of everyday objects. It offers two methods, for rapid low-fidelity and versatile high-fidelity prototyping, and is applicable to a wide variety of materials. Results from a series of technical experiments provide insights into the supported object geometries, compatible object materials, and robustness. Seven example cases demonstrate how ObjectSkin makes it possible to leverage geometries, surface properties, and unconventional objects for prototyping novel interactions for ubiquitous computing.

Video

Publication

Daniel Groeger and Jürgen Steimle
ObjectSkin: Augmenting Everyday Objects with Hydroprinted Touch Sensors and Displays
In Proceedings of the ACM on Interactive, Mobile, Wearable and Ubiquitous Technologies, Vol. 1, No. 4

@article{Groeger:2018:OAE:3178157.3161165,
author = {Groeger, Daniel and Steimle, J"{u}rgen},
title = {ObjectSkin: Augmenting Everyday Objects with Hydroprinted Touch Sensors and Displays},
journal = {Proc. ACM Interact. Mob. Wearable Ubiquitous Technol.},
issue_date = {December 2017},
volume = {1},
number = {4},
month = jan,
year = {2018},
issn = {2474-9567},
pages = {134:1--134:23},
articleno = {134},
numpages = {23},
url = {http://doi.acm.org/10.1145/3161165},
doi = {10.1145/3161165},
acmid = {3161165},
publisher = {ACM},
address = {New York, NY, USA},
keywords = {Fabrication, displays, interactive objects, printed electronics, prototyping, sensors, touch input},
}

Contact me