Sport by Sport: Winter Games

The Olympic Games are held every two years, alternating between summer and winter athletic events. Because of the distinctions between these events -- from distance considerations to weather concerns -- the timing technology can vary greatly from sport to sport. Let's start with winter events.

Photo courtesy USALuge.org

Because Olympic sledding competitors travel at speeds up to 90 miles per hour (145 kph), they win by some of the narrowest margins. When accuracy to the 1,000th of a second or better is key, and timing equipment has to withstand temperatures as low as -30 degrees Fahrenheit (-34 C), special technology is required.

The starting and finish lines at sledding events are equipped with a 0.5-inch to 1-inch infrared beam, which is focused at a receiver that starts or stops the clock when the beam is severed. Laser technology, while effective in the track environment, was replaced by infrared beams for the 2002 Olympics in Salt Lake City after research revealed that falling snow often tripped the laser beam and frost clouded the electric eye, reducing accuracy.

Speed Skating
The timing technology for speed skating is much like that of short-distance track events. The clock is started by the starting gun, and an electric eye sends a signal to the timing computer when each competitor crosses the laser beam at the finish line. Because speed skaters reach speeds up to 30 miles per hour (48 kph), and a skater can win by as little as the tip of a boot, two slit video cameras scan the finish line, time-stamping each image at 2,000 frames per second and sending the complete image to the judges to help determine the winners.

Skiing
Downhill skiing competitors begin their races at starting gates. When these gates open, they send an electronic signal to the timing console to start the clock. Like in the sledding events, an infrared beam is tripped at the finish line to stop the clock.

For the long-distance skiing events, such as cross-country and Nordic, RFIDs attached to each skier's boot send individual signals to antennas buried beneath the snow at the starting line, finish line and points in between. In this way, a skier's starting time, finishing time and progress are all tracked, recorded and broadcast, taking any time penalties into consideration.