AdMos sports Global Navigation Satelite System (GNSS) sensor accuracy compared with state-of-the-art Real-Time Kinematic (RTK)

Engineering of Sport 15 - Proceedings from the 15th International Conference on the Engineering of Sport (ISEA 2024)

In sports science, the ability to analyze athlete performance is crucial. With new technology, researchers are now assisting in generating new race strategies, improving techniques, and developing new equipment. GNSS units are now commonly used to measure acceleration profiles (IMU) and position. Wearable sports watches have started using multiband systems but are still limited to a sampling rate of only 1Hz. The AdMos GNSS sensor (Advanced Sport Instruments (ASI), Lausanne, Switzerland) has a sampling rate of 10Hz from multiple GNSS providers (GPS, Galileo, GLONASS, and BeiDou) and a relative positional accuracy of 30cm and speed accuracy of 0.05m/s according to the manufacturer. The AdMos sensor has been tested in alpine skiing with differential GNSS (dGNSS, a more accurate type of GNSS using a base station for corrections), showing large errors in instantaneous position but acceptable accuracy in some velocity measurement applications and when measuring the average of multiple turns. It suggests using an Inertial navigation system (INS) together with dGNSS to improve ground truth measurements. Real-time Kinematic Positioning (RTK) is another GNSS technology that is primarily used in positioning applications where extreme accuracy is needed. It works similarly to dGNSS by using base stations with a known location to make positional corrections but is considerably more accurate. The Applanix POS MV WaveMaster II INS reports a horizontal positioning accuracy of +/- 8mm using RTK (Trimble Applanix, Ontario, Canada), while the Norwegian Mapping Authority reports centimeter-level accuracy. In rowing, sensors can measure performance with 10 Hz GNSS providing average velosity, and a 200Hz IMU capturing movement and acceleration. High GNSS accuracy gives a better link between specific movements (IMU) and the average velocity (GNSS) which can lead to a better understanding of movements that hinder or enhance performance. Therefore, in this paper, we compare the claimed accuracy of the AdMos sensor with a stateof-the-art RTK INS system, providing information accuracy for evaluating athlete performance.