FIFA has resisted the introduction of goal-line technology for some years as the board felt it was not good for the game. However, a series of goal line incidents has urged the association to revisit the issue. Since the many controversial decisions at the 2010 FIFA World Cup, including the famous denial of Frank Lampard’s goal against Germany, FIFA has decided to introduce computerized aid for officials amending the laws of the game. In a two-part series, our blogger walks you through some interesting GLT technologies and why the Football world is divided in its stance on their deployment.
With several unfair-play calls screamed for by team coaches and managers, it is quite a point to debate about soccer’s incomplete acceptance of goal line technologies such as hawk-eye – a product that is widely exploited by games such as tennis and cricket to maintain a high degree of fair play. It raises the doubt even more because soccer otherwise is a tech-savvy game what with its hi-tech fabrics, divot-defying cleats, and dynamic new ball technology. The Fédération Internationale de Football Association (FIFA) sticks cameras everywhere it possibly can stick them for TV spectators enjoy hits and misses from every conceivable angle. Yet, there is that one blind spot – and perhaps it is where the game needs it most – on the goal line.
GLT in many avataars
The main technologies used in football are those produced by U.K. Company Hawk-Eye Innovations, and German companies Cairos Technologies AG and Goal Control. Many patent applications have been filed describing different goal line technologies. Though we see these technologies being implemented as late as 2012, the first ever patent published describing goal-line technology comes from Germany (DE2051386) in 1970 as a response to the famous 1966 debatable goal from soccer legend Geoff Hurst leading England to their first ever World Cup victory.
Who wins the GLT point?
Goal line technology is a bundle of technologies that together monitors the path of the ball and detects when it crosses the goal line, eliminating human error is deciding a goal point. The systems currently approved by FIFA are broadly based either on camera-tracking or magnetic field sensors.
Hawk-eye uses a network of high-speed video cameras to track a ball’s position at a given time via triangulation to track the position and flight of the ball. Six cameras are placed at different locations around the area of play, ensuring that the goal is detected at times when players are huddled together at the goal mouth (for example, corners). As long as the ball is 25 percent visible, Hawk-Eye can track it.
The technology was deployed in the 2013-2014 Premier League season in the UK and is powered by patent application WO2001041884 developed by artificial intelligence expert Paul Hawkins. Images are processed by a bank of computers in real time and sent to a central computer programmed to analyse a predefined playing area according to the rules of the game. In each frame sent from each camera, the system identifies the cluster of pixels that corresponds to the image of the ball. It calculates for each frame the three-dimensional position of the ball by comparing its position at the same instant in time on a least two cameras placed in different locations.
GoalControl 4D is another GLT technology that absolutely dismisses the need for a referee to consult a replay booth. The system features 14 high speed cameras that are mounted around the stadium, seven directed to each of the goal lines. The camera is capable of taking 500 pictures per seconds and the ball’s movement within 5 millimetres (0.20 in). The smooth transfer of the more than 500 images a second from the cameras is ensured by a multimode fiber-optic network based on industrial switches and Gigabit multimode extenders from Microsens. The referee is equipped with a watch that signals a goal. This system – based on patent applications WO2014059971 and WO2013083112 – was approved during the 2014 World Championship in Brazil.
GoalRef is a German-Danish technology that was tested during the Danish Superliga in 2012. The 2012 FIFA Club World Cup was the first tournament where GoalRef was used by a match referee. Based on patent applications WO2004076003, WO2006094508 and WO2009046722, GoalRef relies on the principle of electromagnetic induction. A low frequency magnetic field is generated around the goal, which is monitored by coils installed in the goal posts and crossbar. The ball is fitted with a passive electronic circuit. A system detects the passing of the ball through the magnetic field and sends a radio signal in real time to a wrist watch worn by the referee.
The Cairos GLT System is another contender for this pride position on the field. Based on four different patent applications – WO2007128406, WO2008043443, WO2008104247 and WO2010075963 – the Cairos system involves embedding thin cables in the turf of the penalty area and behind the goal line.
The electrical current that runs through the cables generates a magnetic field. A sensor suspended in the ball measures the magnetic fields as soon as the ball comes into contact and transmits data about its location to receivers located behind the goal that relay the data to a central computer. If the computer determines the ball has crossed the goal line, a radio signal is transmitted to the referee’s watch within a split second.
Now, Cairos teamed up with Adidas who “developed the suspension system for the ball, so that it keeps our chip safe inside the ball even when you kick the ball very hard. This system failed phase one of testing. There’s more to this war to win the GLT provider hat in my next blog.
(Feature image source: https://pixabay.com/en/referee-sports-fair-person-man-1149014/)