Validity of a Magnet-Based Timing System Using the Magnetometer Built into an IMU.

Area of Science:

• Sports Science
• Biomechanics
• Wearable Technology

Background:

• Inertial measurement units (IMUs) are increasingly used in sports for performance monitoring.
• Accurate timing systems are crucial for evaluating short-duration sports actions.

Purpose of the Study:

• To validate a novel magnet-based timing system (M-BTS) for timing short sports actions.
• To assess the accuracy of an IMU's magnetometer for sports timing applications.

Main Methods:

• Forty-eight athletes and eight skiers performed 60-m sprints and ski slalom, respectively.
• A magnet-based timing system (M-BTS) used IMU magnetometers to detect magnets placed along courses.
• Timing data from M-BTS was validated against traditional photocells.

Main Results:

• The M-BTS demonstrated high validity, with 95% error intervals below 0.077 s for running and 0.050 s for ski slalom.
• The system successfully detected magnetic field peaks generated by passing magnets.

Conclusions:

• The magnet-based timing system (M-BTS) using IMUs is a valid tool for timing short-duration sports actions.
• This technology offers potential for future research by enabling signal selection from integrated IMU sensors.