GoalControl for Brazil 2014
April 2, 2013Soccer - like any sport - has its share of nightmares for hardcore fans.
Some of the most dreadful ones for England supporters are Maradona's "hand of God" - a handball that was counted a goal in a 1986 World Cup quarter-final match against Argentina - and a 2010 Frank Lampard goal, which didn't count for England in a match against Germany because the referee had missed it.
But FIFA - the body that governs world soccer - hopes to make scoring fairer in football with the use of goal line technology (GLT).
In Februray, it confirmed that goal line technologies would be used at the 2014 World Cup in Brazil. And it's now chosen Germany's GoalControl as the first system to be used at the championship.
Torben Hoffmann, a former Bundesliga footballer, welcomes FIFA's decision to use goal line technology.
"[At] the end of the day, there's a lot hanging on football - there's so much invested," says Hoffmann.
The beautiful game is big business.
It isn't just about the celebrity players who are paid a lot of money. It is also about the sponsors who pump in loads of money in the hope of their brands getting noticed by the millions of football fans around the world. Alone the English Premier league - a league competition of England's top 20 clubs - is worth billions of dollars.
Soccer goes 3D
In all, FIFA has licensed four goal line technologies.
They include UK-based Hawk-Eye, and Germany's Cairos Technologies, GoalRef, and the winner of the bid, GoalControl.
GoalControl was the last of the goal detection systems to be awarded a license by FIFA.
The system uses 14 cameras (seven for each goal), mounted under the stadium's roof. Using special software, the system creates 3D images of the ball's position around the goal.
"The system is able to send out a signal when the ball crosses the line, which then is routed to the referee's watch within a second," says Dirk Broichhausen, GoalControl's managing director.
Every second, the 14 cameras produce 500 frames - that's 2 gigabytes of data - which is then transmitted to 15 computers via fiber optic cables.
But ultimately the decision on whether a goal has been scored still lies with the referee - the technology will only serve as an aid for match officials.
Similar systems - such as Hawk-Eye - have already found their fans in tennis.
The Hawk-Eye system has been used in tennis since 2005. Having so many cameras around the stadium - providing images from a number of different angles - allows the system to recreate the ball's path and display those images for the fans.
Magnetic fields
FIFA's plans to use goal line technology have also encouraged the use of sensor-based systems.
Germany's Fraunhofer Institute for Integrated Circuits has developed a goal line technology which works like security tags in stores that beep when someone tries to steal something. A magnetic field is created around the goal post and an alert is sent out when the ball crosses the goal line.
"We have a special ball [embedded with a copper coil]," says Fraunhofer's René Dünkler, "and if this ball crosses over the goal line, the intelligent goal detects this and the information is wirelessly transmitted to a wrist watch worn by the referee."
The fourth goal detection system licensed by FIFA is Cairos Technologies' GLT system.
It is similar to Fraunhofer's system. The main difference is that the electric cables that form the magnetic field are buried in the turf. There is also a chip installed in the ball, instead of a copper coil.
'You have to draw the line somewhere'
All this technology could change the game. But could goal line technology do to football what Hawk-Eye has done to tennis?
Since 2005, players have been allowed to raise an arm during play to challenge a line call by an umpire. If the challenge is successful, the player is either awarded the point, or the point is replayed.
But former footballer Torben Hoffmann doubts whether similar challenges would work in football.
"You have to draw the line somewhere. I would only want to see them use the goal line technology as an aid," he says.
Even with alerts sent within a second of goals being scored, there is every chance that referees will still bungle plenty of calls on the pitch.
But the technology is here to stay.
The English Premier League is implementing goal line technology this year, giving fans around the world a chance to see how it works in practice. Whether it makes for fairer sports is a whole other question.