TennisSense: A Multi-Modal Sensing Platform for Sport

Sensor technology is rapidly changing the professional sporting landscape. Modern motor racing has been virtually transformed by the introduction of sophisticated drive-by-wire sensor technology , for example. Similarly, the ability to accurately monitor the performance of an athlete during training is having a major influence on a wide range of track and field events. In this project we introduce state-of-the art sensing technology onto the tennis court with a view to facilitating coaches as they train the next generation of tennis superstars. These sensors make it possible for coaches to obtain a second-by-second record of player performance that goes far beyond what can be captured by more traditional techniques; simply eyeballing the player as they move, serve, volley and return, does not reveal what might be going on under the surface in terms of the player's ever-changing performance profile, his/her breathing patterns, and the stresses and strains that they are feeling in their joints and muscles. The project is a collaboration between CLARITY (The Centre for Sensor Web technologies) and Tennis Ireland, the national governing body for tennis, based in Dublin City University. We have instrumented an all-weather tennis court with nine Internet-enabled cameras with built-in microphones. This is linked to a localization system that identifies the player's position to within 15cm by triangulating the radio signal emitted by small tags carried by the players in their pockets. The coach uses a simple wireless device to signal an important event during play via a simple button press. After training, these button presses are synchronized to the video streams. Content analysis mechanisms are then used to define the precise start and end of tennis play around these locations. We do this by tracking the ball in each camera, measuring player speed using the location information and detecting the sound of a ball hitting a racquet. These detected events are used in a variety of Web-based coaching tools. These include (a) being able to view individual tennis strokes from multiple view points, (b) support for online coaching feedback (eg " This shot was the wrong choice given the location of your opponent when you played it "), and (c) an easy way for coaches and athletes to produce person-alized annotated video summaries for players to download and review for motivational purposes. Integrating Smart Materials and Body Sensor Networks By its very nature, this project requires convergence between multiple disciplines in order to …