Inertial Sensors for Baseball

This page contains links to articles about the use of inertial sensors that are attached either to the knob of a bat or to a person. They are used to track motion and orientation. For example, they can be used to map out the trajectory and orientation of a bat during the batter's swing. They can also be used to map out the motion of a pitcher's elbow during the windup and delivery. The links below are not meant to be a complete list but sufficient to give the reader a flavor of how these devices work and what they can be used for. Although I have not yet contributed to the development or testing of these devices, I expect that will change with the new year.

UPDATE: Effective February 5, 2015, I am officially a Technical Advisor to Diamond Kinetics. All the descriptions and links at this site were posted prior to my joining the DK family. For the time being, I will not be providing any updates regarding the specific devices currently being marketed.

I have divided this section into three parts:
Introduction to Inertial Sensors
The Devices Currently Being Marketed
Combining Inertial Sensors with Ball-Tracking Data

Introduction to Inertial Sensors

  • Using Wearable Sensors to Improve Performance, by Bryan Cole (@Doctor_Bryan), published Oct. 21, 2014 in Beyond The Box Score. This article is an excellent introduction to these sensors and what they are used for.
  • A New Technology for Resolving the Dynamics of a Swinging Bat, by Kevin King, Jessandra Hough, Ryan McGinnis, and Noel C. Perkins, Sports Engineering 15, pp 41-52 (2012). This article describes in detail the use of miniatured inertial measurement units (IMU's), specfically accelerometers and gyroscopes, along with wireless technology to track the motion of the bat during the swing. This paper provides the foundation for the technology from which the Diamond Kinetics' SwingTracker device evolved. The authors are faculty and students in the Mechanical Engineering Department of the University of Michigan.

The Devices Currently Being Marketed

Combining Inertial Sensors with Ball-Tracking Capability

A very powerful combination is to combine information about the batter's swing from the devices that attach to the knob of the bat with information about the pitched and batted ball. Here are some links to batting cage facilities than can provide baseball-tracking information.