Victoria Uni plays key role in new offside technology for 2022 World Cup

Researchers at Victoria University played a key role in the debut of new technology to make fast offside calls at this year’s World Cup in Qatar.

Victoria University’s Rob Aughey at the Sevilla FC ground in Spain, ready to test FIFA’s new off-side technology in the lead up to the 2022 World Cup.

When the 2022 FIFA World Cup kicks off in Qatar in November, football fans no longer will have to endure long annoying breaks in the game while referees examine video to confirm or deny a contested goal.

The World Cup will feature new video technology that will allow referees to decide in about 10 seconds whether to rule a goal offside (and thus deny it), compared with the current VAR (video assistant referee) system that can take minutes to decide in a close situation.

The new technology was given the go-ahead by FIFA, the international body that regulates football, after researchers from Victoria University in Melbourne comprehensively tested the new system in March and pronounced it to be accurate.

A VU team led by Rob Aughey from the university’s Institute for Health and Sport took over the stadium of Spain’s famed Sevilla FC in Seville to test the system, known as semi-automated offside technology, on behalf of FIFA.

SAOT works by constantly monitoring the position of all players on the field using 12 cameras in the stadium roof that record 50 frames a second, as well as an inertial detector in the ball that sends data 500 times a second.

The SAOT system creates a computer model of each player – keeping track of up to 29 points on their body – and uses artificial intelligence to issue an automatic alert when a player is offside.

The test area used by Victoria University at the Sevilla FC stadium

The challenge for Professor Aughey was to validate the player tracking technology and show that it could be relied on, even in close situations.

To do so, he had to work in a stadium fitted out with the new technology and make independent measurements of players as they simulated game conditions.

He and his team used a 3D tracking system with 44 infra-red cameras that boasted sub-millimetre accuracy.

It picked up data from reflectors worn by the players that were also placed on the ball.

“We would determine how close their system was to our gold standard,” Professor Aughey said.

Tracking the ball was a challenge because the reflective markers soon became dirty.

“We had a PhD student working on the ball tracking,” he said.

Their first job was to test how well the SAOT system tracked a player as they moved around the field. Then they added more players, which can be tricky for an optical system such as SAOT. “You might get a player blocking a camera view,” Professor Aughey said.

Once these basics had been checked, they moved on to testing how well the system dealt with the offside rule, notorious for being one of the most confusing in the rule book of any widely played sport.

Balls used in testing, with reflectors attached

Designed to prevent players lurking too close to their opponent’s goal (which is where they want to kick the ball), the rule says that you are offside if you are closer to that goal than any opposition player (except the goalkeeper) at the precise moment that the ball is played by a teammate.

“We had up to six players in the test area at any one time in offside scenarios,” Professor Aughey said.

He said the SAOT system proved to be “incredibly accurate”.

An added twist in the offside rule, which makes the task even more challenging for the new semi-automated system, is that only the positions of a player’s feet, legs, body and head (the parts of the body able to play the ball) are relevant. In other words, if a player’s hand or arm is in an offside position, that doesn’t count, and SAOT must be able to distinguish this.

FIFA president Gianni Infan­tino said earlier this month the new system was “an evolution of the VAR systems that have been implemented across the world”.

“This technology is the culmination of three years of dedicated research and testing to provide the very best for the teams, players and fans who will be heading to Qatar later this year,” Mr Infantino said.

Professor Aughey said his team had been working with FIFA on tracking technology since 2016.

“It’s pretty cool to be involved in things of this scale in world sport,” he said.

Football fans will be relieved to know the new technology does not require players to be wearing the reflectors seen in the picture, which were there only for the testing that was carried out by Professor Aughey’s team.

They will probably also be pleased that the new system is not fully automated, only semi-automated. When it triggers an offside call, a human referee will make the final decision.

There is an added benefit for football supporters.

After each offside call at this year’s World Cup, a computer-generated replay will be shown on screens in the stadium and on television so fans can judge for themselves whether a player was offside.