Validation of wearables for technical analysis of tennis players
- Delgado-García, Gabriel 1
- Siquier Coll, Jesús 2
- Castro Infantes, Santiago 3
- Ruiz Malagón , Emilio J.
- Benito Colio, Berta 1
- González Fernández, Francisco Tomás 4
- 1 Department of Physical Activity and Sports Sciences, Comillas Pontifical University. CESAG, Mallorca
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2
Universidad Pontificia Comillas
info
- 3 Faculty of Physic Activity and Sport. University of Granada, Granada
- 4 Department of Physical Activity and Sports Sciences, University of Granada. Ciencias de la Educación y del Deporte, Melilla University
ISSN: 2695-4508
Datum der Publikation: 2022
Ausgabe: 4
Nummer: 2
Seiten: 56-60
Art: Artikel
Andere Publikationen in: International Journal of Racket Sports Science
Zusammenfassung
The aim of the study was to study the validity of two well-known commercial sensors (Zepp and Qlipp) by comparing the speed data they provide with those of a speed radar and a 3D photogrammetric system. Four tennis players of different levels were part of the present study: one was of competition level (male; 29 years old; 1.89 m; 79 kg) and the other three were of initiation level (20-30 years old and a 24-year-old female). They performed a total of 77 strokes after receiving through a ball machine at a speed of 70 km/h and with the minimum lift effect allowed by the machine. The ball speed measured with the Zepp sensor and with the Qlipp sensor was compared with the speed recorded by a radar (Stalker Pro II, USA) and with a photogrammetric system composed of 4 USB cameras (ELP, China) recording at 100 Hz. The ball and the end of the racket were digitized on the video using the freeware Kinovea and their real 3D coordinates were obtained by applying the DLT algorithm, using the Kinemat tool in the mathematical analysis software GNU Octave. The velocity was calculated by deriving the 3D coordinates using a fifth degree spline. The data of the present work indicate that the hitting kinematics of each player affects the accuracy of the sensor, so we consider that further studies are required to evaluate the error in players of different levels and playing styles. The inertial sensors evaluated in this work seem adequate to measure ball speed in intra-subject studies and the Lin CCC values in the first study and the adjusted values in the second study were almost all greater than 0.75.
Bibliographische Referenzen
- Evans, J. D. (1996). Straightforward statistics for the behavioral sciences. Thomson Brooks/Cole Publishing Co.
- Jaitner, T., & Gawin, W. (2010). A mobile measure device for the analysis of highly dynamic movement techniques, 2(2), 3005-3010. https://doi.org/10.1016/j.proeng.2010.04.102
- Keaney, E. M., & Reid, M. (2018). Quantifying hitting activity in tennis with racket sensors: new dawn or false dawn?. Sports Biomechanics, 19(6), 831-839. https://doi.org/10.1080/14763141.2018.1535619
- Kos, M., Zenko, J., Vlaj, D., & Kramberger, I. (2016). Tennis stroke detection and classification using miniature wearable IMU device. 2016 International Conference on Systems, Signals and Image Processing (IWSSIP), 1-4.
- Reinschmidt, C., & Van den Bogert, T. (1997). KineMat. A MATLAB Toolbox for Three-Dimensional Kinematic Analyses. Calgary, Canada: Human Performance Laboratory, The University of Calgary.; 1997 [cited 2020 Jul 22]. https://isbweb.org/software/movanal/kinemat/
- Shan, C. Z., Sen, S. L., Che Fai, Y., & Su Lee Ming, E. (2015). Investigation of Sensor-based Quantitative Model for Badminton Skill Analysis and Assessment. Journal Teknologi, 72(2). https://doi.org/10.11113/jt.v72.3891
- Yang, D., Tang, J., Huang Y., Xu, C., Li, J., Hu, L., Shen, G., Liang, C-J., & Liu, H. (2017). TennisMaster: an IMU-based online serve performance evaluation system. In Proceedings of the 8th Augmented Human International Conference (AH '17). Association for Computing Machinery, New York, NY, USA, (17), 1–8. https://doi.org/10.1145/3041164.3041186