A Distributed Wearable, Wireless Sensor System for Evaluating Professional Baseball Pitchers and Batters

This paper introduces a compact, wireless, wearable system that measures signals indicative of forces, torques and other descriptive and evaluative features that the human body undergoes during bursts of extreme physical activity (such as during athletic performance). Standard approaches leverage highspeed camera systems, which need significant infrastructure and provide limited update rates and dynamic accuracy. This project uses 6 degree-of-freedom inertial measurement units worn on various segments of an athlete´s body to directly make these dynamic measurements. A combination of low and high range sensors enables sensitivity for both slow and fast motion, and the addition of a compass helps in tracking joint angles. Data from the battery powered nodes is acquired using a custom wireless protocol over an RF link and analyzed offline. Several professional pitchers and batters were instrumented with the system and data was gathered over many pitches and swings. We show some biomechanically descriptive parameters extracted from this data, and highlight ongoing work and system improvements.