Technology expert says FIFA's demands make it difficult to deliver 100 percent judgments.
The IFAB (International Football Associations Board) decided on Saturday (March 5) to extend testing of goal line technology systems for another year with the possibility of them being employed in the 2014 World Cup in Brazil.FIFA recently held trials in Switzerland for technology companies. The test was to determine with 100 percent accuracy if a soccer ball had crossed the goal line and deliver the answer in about one second. None passed the test.
Firth, technology editor of New Scientist magazine, said on Friday (March 4) lesser demands could easily be met, with systems delivering such answers in tennis, rugby and cricket in about ten seconds.
But FIFA wish to keep a "no goal" ball in play without disturbing the flow of the game. So if a ball has indeed crossed the goal line, any system must be able to inform the referee immediately so that they can blow the whistle and declare the goal quickly.
Firth said that soccer poses particular difficulties with goal posts, which have to be used to measure if a ball has crossed the line, regularly being hit by balls, players or high winds.
He also pointed out that systems used in tennis and cricket must be able to see at least 25% of the ball in order to calculate where the ball is at any one time. Yet a goal line scramble can mean that the ball is obscured completely by players' bodies on the goal line, making it especially difficult to determine if the ball has crossed the line.