Affiliation:
1. Faculty of Teacher Education, Culture and Sports, Western Norway University of Applied Sciences, NO-6856 Sogndal, Norway
Abstract
Modern analyses of football games require precise recordings of positions and movements. The ZXY arena tracking system reports the position of players wearing a dedicated chip (transponder) at high time resolution. The main issue addressed here is the quality of the system’s output data. Filtering the data to reduce noise may affect the outcome adversely. Therefore, we have examined the precision of the data given, possible influence by sources of noise, the effect of the filtering, and the accuracy of the built-in calculations. The system’s reported positions of the transponders at rest and during different types of movements, including accelerations, were recorded and compared with the true positions, speeds, and accelerations. The reported position has a random error of ≈0.2 m, defining the system’s upper spatial resolution. The error in signals interrupted by a human body was of that magnitude or less. There was no significant influence of nearby transponders. Filtering the data delayed the time resolution. Consequently, accelerations were dampened and delayed, causing an error of 1 m for sudden changes in position. Moreover, fluctuations of the foot speed of a running person were not accurately reproduced, but rather, averaged over time periods >1 s. Results calculated from measured values appeared accurate and were readily reproduced in a spreadsheet output. In conclusion, the ZXY system reports the position with little random error. Its main limitation is caused by averaging of the signals.
Subject
Electrical and Electronic Engineering,Biochemistry,Instrumentation,Atomic and Molecular Physics, and Optics,Analytical Chemistry
Reference47 articles.
1. International Football Association Board (2018). Laws of the Game, International Football Association Board. Available online: https://digitalhub.fifa.com/m/50518593a0941079/original/khhloe2xoigyna8juxw3-pdf.
2. Match performance and physical capacity of players in the top three competitive standards of English professional soccer;Bradley;Hum. Mov. Sci.,2013
3. High-intensity running in English FA Premier League soccer matches;Bradley;J. Sports Sci.,2009
4. Performance Characteristics According to Playing Position in Elite Soccer;Baron;Int. J. Sports Med.,2007
5. Analysis of High Intensity Activity in Premier League Soccer;Gregson;Int. J. Sports Med.,2009