If they can put collars on dogs that will shock them when they cross an "invisible" fence then I am sure the technology exists to sense when a football crosses a goal line.

I imagine the Referee equiped with a vibrating pager (I wanted to say shock collar) which will go off each time the football crosses the goal line.

This allows the Referee to fully concentrate on when the player is down. Examples: ref sees player's knee hit, and is then paged results in no touchdown. ref is paged and then sees player's knee hit results in touchdown.

(totally unrelated -does anyone know how the first down line visible on the TV but not to the players works?)
-- Zimmy, May 14 2003

SportVision's 1st Down Line for American Football Fans http://www.howstuff...first-down-line.htm
How the 1st Down Line Works. [jurist, Oct 21 2004, last modified Aug 02 2007]

Baseball has something similar. http://www.pvi-inc....vertising/espn.html
Is it live, or Memorex? [ty6, Oct 21 2004]

If you had said shock collar, you might have got a croissant.
-- ato_de, May 14 2003


[ato_de]: for the football players?
-- Cedar Park, May 14 2003


What if you are holding the ball behind you as you cross... your foot touches as you catch the ball.. which is a touchdown, yet the pager wouldn't go off until *after* you cross.
-- bigattichouse, May 14 2003


[Cedar Park] for everyone!
-- ato_de, May 14 2003


NFL rules require the ball to cross. For similar applications perhaps a sensor in the shoes activates a light indicating in/out of bounds or [bigattichouse], (Is this rule for rugby?) rugby score.
-- Zimmy, May 14 2003


Photo Finishes are for races, Instant Replay is for Pornos. Leave it to the Officials.
-- el observador, Jan 06 2004


[jurist] your link died. my condolences.

[Zimmy] If you're really interested in how it works, there's a really nice article about exactly how the first down line is made in this month's edition of "Scientific American", page 100.
-- Overpanic, Jan 06 2004


There could be sensors installed right underground all over the field but particularly around the sidelines and goallines. some sort of device or transponder could be attached to players' knees, elbows, ass, whatever other body parts cause a player to be ruled down. the ball would be equipped with sensors also. this way, you could electronically determine whether the ball crossed the goalline plane before or after a player was down; and more importantly, this would eliminate referees shortchanging one team or teh other by mis-spotting the ball.
-- cocktaillouie, Mar 12 2004


you could use inductors, but with that you need to modify the shells and helmets so the inductor doesnt pick up the metal. There is no way this will work because it will always be challenged by coaches. What if the player actually fumbles the ball in the endzone, and the opposing team picks it up, is it a safety or a td?? and what if the player fumbles but covers it up, will they still rely on coaches challenges and the 360 cams or are they gonna rely on the damn pager devices. Gimme a break, refs have an easy job; "illegal substitution, white, number 75, 5 yard penalty" or "facemask, offense, number 69, 15 yard penalty". How hard can that be??
-- morbiddesire, Mar 14 2004


Actually, in rugby, not only do the player and the ball both have to cross into the try zone, but the player has to touch the ball to the ground in the try zone for the try to be scored.

Brings back painful memories of a high school game where our fly half had made it into the try zone on a breakaway, tried to change direction to run to the middle of the zone to give the kicker a better angle, then due to the wet grass slipped and fell out of the try zone from the back, putting the ball out of bounds. Ouch.
-- Jem, Mar 15 2004



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