There is also a compatible Haptic Material Designer created by Gabriela Vega, Nihar Sabnis, Dennis Wittchen, and Paul Strohmeier. The Designer uses a desktop-based GUI for creating material experiences with Haptic Servos.
PCB versions of the VoxEMG. The v3.1 eTextile Configuration (left) features castellated inputs for conductive thread input and loops for textile integration. The v3.1.2 Bela Mini Capelet (middle, right) slots directly into the A0 and A1 analogue inputs, power, and ground from the Bela Mini.
about
Haptic Servos were designed by the Sensorimotor Interaction Group (senSInt) at the Max Planck Institute for Informatics (MPI-INF). The main contributors are Paul Strohmeier, Nihar Sabnis, Dennis Wittchen, Valentin Martinez-Missir, and myself. The designs encapsulate all timing-sensitive elements and hardware setup to create a rich variety of material experiences. Research work, primarily undertaken by Nihar in his PhD research, explores how Haptic Servos can be used to render continuous and dynamic, motion-coupled material experiences in tangible user interfaces.
Haptic Servos enable rapid rendering of diverse material experiences in a plug-and-play sensor-actuator path. The open source Haptic Servo shield is compatible with the Arduino IDE/Teensyduino and PlatformIO. The firmware has been tested for both the Teensy 3.5 and Teensy 4.1 microcontrollers.
The Haptic Servo signal flow diagram between analogue sensor, control device/microcontroller, and actuator.
related publications:
2023
Tactile Symbols with Continuous and Motion-Coupled Vibration: An Exploration of Using Embodied Experiences for Hermeneutic Design
Nihar Sabnis, Dennis Wittchen, Gabriela Vega, and 2 more authors
In Proceedings of the 2023 CHI Conference on Human Factors in Computing Systems, Apr 2023
With most digital devices, vibrotactile feedback consists of rhythmic patterns of continuous vibration. In contrast, when interacting with physical objects, we experience many of their material properties through vibration which is not continuous, but dynamically coupled to our actions. We assume the first style of vibration to lead to hermeneutic mediation, while the second style leads to embodied mediation. What if both types of mediation could be used to design tactile symbols? To investigate this, five haptic experts designed tactile symbols using continuous and motion-coupled vibration. Experts were interviewed to understand their symbols and design approach. A thematic analysis revealed themes showing that lived experience and affective qualities shaped design choices, that experts optimized for passive or active symbols, and that they considered context as part of the design. Our study suggests that adding embodied experiences as a design resource changes how participants think of tactile symbol design, thus broadening the scope of the symbol by design for context, and expanding their affective repertoire as changing the type of vibration influences perceived valence and arousal.
@inproceedings{Sabnis_CHI23_TactileSymbols,title={{Tactile Symbols with Continuous and Motion-Coupled Vibration: An Exploration of Using Embodied Experiences for Hermeneutic Design}},author={Sabnis, Nihar and Wittchen, Dennis and Vega, Gabriela and Reed, Courtney N. and Strohmeier, Paul},year={2023},month=apr,booktitle={{Proceedings of the 2023 CHI Conference on Human Factors in Computing Systems}},location={Hamburg, Germany},publisher={Association for Computing Machinery},address={New York, NY, USA},series={CHI '23},articleno={688},numpages={19},doi={10.1145/3544548.3581356},isbn={9781450394215},url={https://doi.org/10.1145/3544548.3581356},}
Haptic Servos: Self-Contained Vibrotactile Rendering System for Creating or Augmenting Material Experiences
Courtney N. Reed*, Nihar Sabnis*, Dennis Wittchen*, and 3 more authors
In Proceedings of the 2023 CHI Conference on Human Factors in Computing Systems, Apr 2023
When vibrations are synchronized with our actions, we experience them as material properties. This has been used to create virtual experiences like friction, counter-force, compliance, or torsion. Implementing such experiences is non-trivial, requiring high temporal resolution in sensing, high fidelity tactile output, and low latency. To make this style of haptic feedback more accessible to non-domain experts, we present Haptic Servos: self-contained haptic rendering devices which encapsulate all timing-critical elements. We characterize Haptic Servos’ real-time performance, showing the system latency is <5 ms. We explore the subjective experiences they can evoke, highlighting that qualitatively distinct experiences can be created based on input mapping, even if stimulation parameters and algorithm remain unchanged. A workshop demonstrated that users new to Haptic Servos require approximately ten minutes to set up a basic haptic rendering system. Haptic Servos are open source, we invite others to copy and modify our design.
@inproceedings{Sabnis_CHI23_HapticServos,title={{Haptic Servos: Self-Contained Vibrotactile Rendering System for Creating or Augmenting Material Experiences}},author={Reed*, Courtney N. and Sabnis*, Nihar and Wittchen*, Dennis and Pourjafarian, Narjes and Steimle, J\"{u}rgen and Strohmeier, Paul},year={2023},month=apr,booktitle={{Proceedings of the 2023 CHI Conference on Human Factors in Computing Systems}},location={Hamburg, Germany},publisher={Association for Computing Machinery},address={New York, NY, USA},series={CHI '23},articleno={522},numpages={17},doi={10.1145/3544548.3580716},isbn={9781450394215},url={https://doi.org/10.1145/3544548.3580716},}
2022
Vibro-Touch
Courtney N. Reed, and Nihar Sabnis
In ACM TEI Studio “How Tangible is TEI?” Exploring Swatches as a New Academic Publication Format, Feb 2022
In our research, we examine tactile representations which are used for user interaction and system notifications. This swatch works as an interface to store and playback vibrotactile stimuli. This allows for easy, cost effective (\~€20) reproduction and exploration of tactile feedback. Typically, feedback designed and used in research is described through written formats. This swatch provides a companion to physically experience the vibrations. The tactile sensation is stored on a microcontroller and played back through a speaker which works as an actuator. The swatch could be given to others to test and experience different sensations in a simplified, modular format. For instance, rather than redesigning feedback for each new study, the tactile feedback could be shared and reproduced for new research. The code on the microcontroller can be changed or updated to have multiple "swatches" in one. In other applications, the swatch could also play audio feedback.
@inproceedings{Reed_TEI22_Vibrotouch,title={{Vibro-Touch}},author={Reed, Courtney N. and Sabnis, Nihar},year={2022},month=feb,booktitle={{ACM TEI Studio ``How Tangible is TEI?'' Exploring Swatches as a New Academic Publication Format}},location={Daejeon, Republic of Korea},}
