Open source code for Expressive, Scalable, Mid-air Haptics with Synthetic Jets . This paper was published in the ACM Transactions on Computer-Human Interaction in January 2024. The paper will be presented at CHI 2024. Contact me with questions here!
- Demo Code has code used for a few of the demos with moving parts, i.e. steering wheel servos, unity code used for the HMD demo, etc.
- Demo Stimuli has audacity files with the stimuli wavs for each application
- Design Files contain all the laser cut files used for the applications
- Stimuli Eliciation Study contains the stimuli used for the elicitation study
- Stimuli Recognition Study contains all the stimuli used for the recognition study, as well as the python files used to automate the study.
Instructables Link The BoM is in the repository - these are just the materials we use, but synjets can be built with many different speakers, for a wide variety of devices!
Here is a brief summary of the assembly instructions.
- Choose the speaker you are using. Roughly, the larger the speaker, the farther/stronger the range of the synjet.
- Fabricate the enclosure. The design files compatible with the speakers we used can be found in this repository. We laser cut these out of acrylic to put on the speakers. If you are using our tiniest speaker, instead poke a small hole in some cardstock and glue that on top.
- For all speakers but the largest one, the small class D amplifier can be used. It can be powered either through a 5V USB connection from your computer, or a 9-12V power adapter. Either way, strip one end of the cable and attach power to VCC and ground to GND on the amplifier.
- Attach wires to the two terminals of your speaker, and then wire them to R+ and R- (or L+ and L-). The polarity doesn't really matter. The other speaker terminals can be used for a second synjet, just be cognizant of the L/R audio signals coming from the audio cable.
- Plug in the USB power and an audio cable to your computer.
- Using Audacity (or any other audio software, like Audition), play an appropriate sine wave for your synjet. Start with the resonant frequency of your speaker (which can be found on the online spec sheet), and then you can tune it from there. You can also find demo WAV files in the "Stimuli Recognition Study" folder on the Github.
- Slowly turn the knob up. If everything went right you should be able to feel a stream of air!
This work is licensed under a GPL v 2.0 License file present in the repo. Please contact innovation@cmu.edu if you would like another license for your use.
Vivian Shen, Chris Harrison, and Craig Shultz. 2024. Expressive, Scalable, Mid-air Haptics with Synthetic Jets. ACM Trans. Comput.-Hum. Interact. 31, 2, Article 14 (April 2024), 28 pages. https://doi.org/10.1145/3635150
BibTex Reference:
@article{10.1145/3635150,
author = {Shen, Vivian and Harrison, Chris and Shultz, Craig},
title = {Expressive, Scalable, Mid-air Haptics with Synthetic Jets},
year = {2024},
issue_date = {April 2024},
publisher = {Association for Computing Machinery},
address = {New York, NY, USA},
volume = {31},
number = {2},
issn = {1073-0516},
url = {https://doi.org/10.1145/3635150},
doi = {10.1145/3635150},
abstract = {Non-contact, mid-air haptic devices have been utilized for a wide variety of experiences, including those in extended reality, public displays, medical, and automotive domains. In this work, we explore the use of synthetic jets as a promising and under-explored mid-air haptic feedback method. We show how synthetic jets can scale from compact, low-powered devices, all the way to large, long-range, and steerable devices (Figure 1). We built seven functional prototypes targeting different application domains to illustrate the broad applicability of our approach. These example devices are capable of rendering complex haptic effects, varying in both time and space. We quantify the physical performance of our designs using spatial pressure and wind flow measurements and validate their compelling effect on users with stimuli recognition and qualitative studies.},
journal = {ACM Trans. Comput.-Hum. Interact.},
month = {jan},
articleno = {14},
numpages = {28},
keywords = {Non-contact haptics, mid-air haptics, synthetic jets}
}