A Real-Time Wearable Assist System for Upper Extremity Throwing Action Based on Accelerometers

Area of Science:

• Sports Science
• Biomechanics
• Wearable Technology

Background:

• Baseball throwing involves complex, continuous upper extremity movements across six distinct phases.
• Accurate analysis of throwing mechanics is crucial for player performance, injury prevention, and rehabilitation.
• Existing action recognition systems often lack the precision required for nuanced, continuous movement analysis.

Purpose of the Study:

• To develop a real-time wearable assist system for analyzing and improving upper extremity throwing actions.
• To enable precise recognition of six serial throwing phases (wind-up to follow-through) using inertial measurement unit (IMU) sensors.
• To provide players with immediate feedback for learning, rectification, and rehabilitation of throwing mechanics.

Main Methods:

• Utilized accelerometers from IMU sensors to capture three-axial acceleration signals during throwing actions.
• Applied Kalman filtering for noise reduction, followed by leveling and labeling for data processing.
• Employed the Longest Common Subsequence (LCS) method to recognize the six serial phases of the throwing action by comparing sequence data.
• Integrated intelligent functions for status recognition, movement initiation, and posture transition analysis.

Main Results:

• Achieved an average recognition accuracy of 95.14% for all three users in experimental trials.
• Demonstrated successful real-time recognition of complex, continuous throwing actions with high precision.
• The developed system effectively analyzed posture and provided precise comments for improving throwing actions.

Conclusions:

• The developed real-time wearable assist system accurately recognizes upper extremity throwing actions.
• The system's high accuracy (average 95.14%) validates its effectiveness for baseball players.
• This technology offers a valuable tool for enhancing throwing performance, learning, and rehabilitation in sports.