Fully automatic time

Fully automatic time (abbreviated FAT) is a form of race timing in which the clock is automatically activated by the starting device, and the finish time is either automatically recorded, or timed by analysis of a photo finish. The system is commonly used in track and field racing, as well as Dog and Horse Racing and Dog Racing; in these fields, a photo finish is used. It is also used in competitive swimming, for which the swimmers themselves record a finish time by touching a touchpad at the end of a race. In order to verify the equipment, or in case of failure, a backup system (typically manual) is usually used in addition to FAT. [For example the USA Swimming [http://www.usaswimming.org/USASWeb/_Rainbow/Documents/6d2c5425-0029-4a35-b69a-ced23305db8a/a-CHAPTER%209%20Timing%20%20October%202006.pdf Guide to Officiating] requires that " [...] (because of the potential for failure) and always to verify proper operation, all times from electronic timing equipment (whether touchpads or buttons) must both be verified and backed-up by another timing system. The backup must always include at least one stopwatch."]

In races started by a starting gun, a sensor is typically attached to the gun which sends an electronic signal to the timing system when fired. Alternatively, a starting light or sound which is electronically triggered (such as a horn), the system is typically also wired to the timing system. In sports that involve a finish line that is crossed (rather than a touch finish, as in swimming), the current finishing system is a photo finish which is then analysed by judges.

The current photo-finish system used in Olympic competition, as well as other top-level events uses a Digital Line-Scan Camera aimed straight along the finish line. This camera has an image field only a few pixels wide, with a single frame forming a narrow image only of the finish line, and anything which is crossing it. During a race, the camera takes images at an extremely high frame rate (the exact rate depends on the system, but can be in the thousands of frames per second). Computer software then arranges these frames horizontally to form a panoramic image which effectively displays a graph of the finish line (and anything crossing it) as time passes, with time denoted on the horizontal axis.

Before the advent of digital photography, (and still available as an alternative), a similar film-based system was used, consisting of a slit which a strip of film is advanced past at a constant rate to produce a similar panoramic image to the digital system. Less-expensive video-based systems also exist; however, VHS and SVHS frame rates limit the timing precision that can be achieved by these media.

FAT in athletics

According to the IAAF, any record in athletics (world, Olympic, or national) or qualifying time for Olympic Games or World Championships set in a sprint event must be timed by a FAT system to be valid. International rules also stipulate that 0.24 seconds be added to any hand-timed mark in the 100 m or 200 m event, and 0.14 seconds to any hand-timed mark in the 400 m event. In the case of an adjusted manual time to FAT timing, and an original FAT time being equivalent, the FAT time will be considered more accurate, and thus the athlete will be given the higher seed, or the victory, if that is the case.

References

ee also

*Photo finish