Ball/Court Interaction Analysis

The high speed video system is comprised of a high resolution imager camera head unit equipped with an 1/10,000 second electronic shutter and SVHS format video cassette recorder unit supporting both 250 and 500 frames per second. For the purpose of the experiment the system was set to capture at the rate of 250 fps with a shutter of 1/2,000 second.

Reference blocks are comprised of 1"x1"x12" wood blocks painted white for better visibility. Positioned near the court center line, they serve as reference for calibrating the scale during the motion analysis.

The camera was fixed on the side line perpendicular to the centerline of the court. The lens was adjusted to include in the frame a full bounce cycle - that is include the incoming ball trajectory, court impact and rebound and exit trajectory with apogee. In order to maximize the accuracy of the analysis each set of experiments was determined valid only if it met the following criterion:

The experiments were conducted to obtain at least five valid ball bounces for each set.

After recording the ball bounce experiments on video, the video clips were catalogued and 5 valid ball bounces were picked for each set. Data sets that lacked bounce height were noted in the evaluation. The video clips were then transferred onto a computer to conduct the analysis.