Tennis Dynamics Lab
Professor Karl Hedrick
Summer 2012

Team members: Corbin Halliwell, Andrew Kooker, Tony Sung
My responsibilities: electromechanical design, some microcontroller programming

During the summer between my sophomore and junior years, I worked as a paid researcher in the Tennis Dynamics Lab for the Court Pace Rating project.

The motivation behind this project was to find a cost effective way of measuring the speed of tennis balls before and after an impact with the court. If the ball is to be fired at a prescribed angle, then the change in velocity after impact can be used to quantify and compare different tennis courts. This is particularly useful when tennis courts are layed, and the client wants certain bounce characteristics.

This has traditionally been done with very expensive high speed cameras. However, by using a simple laser array and a little vector math, we can get equivalent performance for about 1-2% of the cost. (Compared to for example, a $10,000 high speed camera.)

Initial idea sketches.

Testing our prototype on a tennis court. Corbin on the right, and Yisi, a new member, on the left.

Section cut of the wooden proof of concept. Two holders for laser modules above, and two rails for light sensors. To measure the inbound velocity, light gates have been integrated into our air cannon (not shown). These drawings were made after construction for documentation purposes.