Application of MEMS Inertial Sensors to Sports Training Devices

Professor Noel Perkins
Arthur F. Thurman Professor
Mechanical Engineering Dept.
University of Michigan
ABSTRACT:
The fine motor control needed in many sports (and other activities) often results by respecting the age-old adage that “practice makes perfect.” However, practice alone does not guarentee success, and particularly so when it only leads to fine tuning a fundamentally poor technique. This talk will review recent inventions used for diagnosing proper technique by measuring the motion of the sports equipment used for golf, tennis, baseball, fly casting, crew, etc.

The inventions employ MEMS inertial sensors in compact, low-power modules to transduce 2-D and 3-D rigid body dynamics. Combinations of accelerometers and angular rate gyros are employed to measure the acceleration and angular velocity vectors of a rigid body of sports equipment. Inspection of this raw data, or integrated forms of this data, reveal metrics that readily distinguish good vs. poor technique. More subtle differences amoung the highest calibre techniques can often be distinguished as well. The identification and measurement of quantitative performance metrics open the door to novel sports training aids. Sensor modules engineered for both wired and wireless operation will be reviewed and their application to golf and to fly casting will be discussed in some detail.