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From 2D to 3D: Facilitating Single-Finger Mid-Air Typing on QWERTY Keyboards with Probabilistic Touch Modeling

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Yuanchun ShiAuthors Info & Claims

Proceedings of the ACM on Interactive, Mobile, Wearable and Ubiquitous Technologies, Volume 7, Issue 1

Article No.: 38, Pages 1 - 25

https://doi.org/10.1145/3580829

Published: 28 March 2023 Publication History

Abstract

Mid-air text entry on virtual keyboards suffers from the lack of tactile feedback, which brings challenges to both tap detection and input prediction. In this paper, we explored the feasibility of single-finger typing on virtual QWERTY keyboards in mid-air. We first conducted a study to examine users' 3D typing behavior on different sizes of virtual keyboards. Results showed that the participants perceived the vertical projection of the lowest point on the keyboard during a tap as the target location and inferring taps based on the intersection between the finger and the keyboard was not applicable. Aiming at this challenge, we derived a novel input prediction algorithm that took the uncertainty in tap detection into a calculation as probability, and performed probabilistic decoding that could tolerate false detection. We analyzed the performance of the algorithm through a full-factorial simulation. Results showed that the SVM-based probabilistic touch detection together with a 2D elastic probabilistic decoding algorithm (elasticity = 2) could achieve the optimal top-5 accuracy of 94.2%. In the evaluation user study, the participants reached a single-finger typing speed of 26.1 WPM with 3.2% uncorrected word-level error rate, which was significantly better than both tap-based and gesture-based baseline techniques. Also, the proposed technique received the highest preference score from the users, proving its usability in real text entry tasks.

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Cited By

Liu ZLiu XWang L(2024)CrossKeys: Text Entry for Virtual Reality Using a Single Controller via Wrist RotationInternational Journal of Human–Computer Interaction10.1080/10447318.2024.2358456(1-13)Online publication date: 5-Jun-2024
https://doi.org/10.1080/10447318.2024.2358456
Zhao JWang CXie LFeng YLu S(2024)Research on pedestrian counting based on millimeter waveCCF Transactions on Pervasive Computing and Interaction10.1007/s42486-023-00145-66:1(82-100)Online publication date: 18-Feb-2024
https://doi.org/10.1007/s42486-023-00145-6
Song CMei LLi BZhou X(2024)Dynamic Liveness Detection Based on Fusion of mmWave Radar and VisionWireless Sensor Networks10.1007/978-981-97-1010-2_4(42-55)Online publication date: 1-Mar-2024
https://doi.org/10.1007/978-981-97-1010-2_4
Show More Cited By

Index Terms

From 2D to 3D: Facilitating Single-Finger Mid-Air Typing on QWERTY Keyboards with Probabilistic Touch Modeling
1. Human-centered computing
  1. Human computer interaction (HCI)
    1. Interaction paradigms
      1. Virtual reality
    2. Interaction techniques
      1. Text input

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cover image Proceedings of the ACM on Interactive, Mobile, Wearable and Ubiquitous Technologies

Proceedings of the ACM on Interactive, Mobile, Wearable and Ubiquitous Technologies Volume 7, Issue 1

March 2023

1243 pages

EISSN:2474-9567

DOI:10.1145/3589760

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Copyright © 2023 ACM.

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Published: 28 March 2023

Published in IMWUT Volume 7, Issue 1

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the grant from the Institute for Guo Qiang, Tsinghua University
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Cited By

Liu ZLiu XWang L(2024)CrossKeys: Text Entry for Virtual Reality Using a Single Controller via Wrist RotationInternational Journal of Human–Computer Interaction10.1080/10447318.2024.2358456(1-13)Online publication date: 5-Jun-2024
https://doi.org/10.1080/10447318.2024.2358456
Zhao JWang CXie LFeng YLu S(2024)Research on pedestrian counting based on millimeter waveCCF Transactions on Pervasive Computing and Interaction10.1007/s42486-023-00145-66:1(82-100)Online publication date: 18-Feb-2024
https://doi.org/10.1007/s42486-023-00145-6
Song CMei LLi BZhou X(2024)Dynamic Liveness Detection Based on Fusion of mmWave Radar and VisionWireless Sensor Networks10.1007/978-981-97-1010-2_4(42-55)Online publication date: 1-Mar-2024
https://doi.org/10.1007/978-981-97-1010-2_4
Kim TKarlson AGupta AGrossman TWu JAbtahi PCollins CGlueck MSurale H(2023)STAR: Smartphone-analogous Typing in Augmented RealityProceedings of the 36th Annual ACM Symposium on User Interface Software and Technology10.1145/3586183.3606803(1-13)Online publication date: 29-Oct-2023
https://dl.acm.org/doi/10.1145/3586183.3606803
Liang CWang XLi ZHsia CFan MYu CShi Y(2023)ShadowTouch: Enabling Free-Form Touch-Based Hand-to-Surface Interaction with Wrist-Mounted Illuminant by Shadow ProjectionProceedings of the 36th Annual ACM Symposium on User Interface Software and Technology10.1145/3586183.3606785(1-14)Online publication date: 29-Oct-2023
https://dl.acm.org/doi/10.1145/3586183.3606785
Shen JDudley JKristensson P(2023)Fast and Robust Mid-Air Gesture Typing for AR Headsets using 3D Trajectory DecodingIEEE Transactions on Visualization and Computer Graphics10.1109/TVCG.2023.332021829:11(4622-4632)Online publication date: 2-Oct-2023
https://dl.acm.org/doi/10.1109/TVCG.2023.3320218

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