A DCU team has made the ultimate tennis court where computers and video help players to improve and give coaches a new way to monitor performance, writes Dick Ahlstrom
A RESEARCH PROJECT has taken the idea of "watching a tennis match" to a new dimension. The sensing and visual analysis system scrutinises the players using no fewer than nine video recorders and the player's location on court can be tracked in real time to within 15cm.
The object is to give coaches and players a powerful new tool to help improve performance, explains Dublin City University's Prof Noel O'Connor, one of the lead researchers in the project.
The research is part of the work programme established by the Science Foundation Ireland-funded "Clarity" CSet, a €16.4 million centre for science, engineering and technology announced earlier this year for the study of "sensor web" technologies.
Clarity is a joint effort between DCU and University College Dublin under the directorship of UCD's Prof Barry Smyth. Prof O'Connor is a principal investigator within the Clarity team.
He went with ideas for the development of tennis coaching to representative body, Tennis Ireland. "The idea is we want to be able to bring the next generation of sensing technology into tennis coaching," he says. "We are creating a sensed environment in which tennis players can train and compete."
The researchers took over one of Tennis Ireland's covered courts at its Hampstead Park facility in Glasnevin, installing advanced technology including nine high-resolution cameras, with one directly above the court, all of which can capture sound as well.
They also set up a number of positional sensors that can track player movement around the court. The players wear a small tag about the size of a matchbox.
"These tags emit a radio frequency pulse when the tag is in motion," explains Prof O'Connor. Multiple sensors are able to locate the players on the court through triangulation. "We can map the tennis player's exact location anywhere on the court to within 15cms."
None of this is based on the "Hawk-eye" technology now being used in tennis, cricket and other sports to capture the trajectory of a moving ball, Prof O'Connor stresses. This was used in the recent Wimbledon competition to call the ball in or out of play.
The Clarity approach is much different, the player is the object of the analysis, his position on court, serving style, backhand and forehand movement and other factors that affect performance. "This is about giving players information about their training."
The initial version of the system, which has yet to acquire a formal name, is already up and running so it can be assessed by players and coaches, says Prof O'Connor.
A player can begin a session, for example in competitive play or say just serving or returning backhand shots. "For each point in time we have nine separate views of the player," Prof O'Connor explains.
The coach watches proceedings and if he sees something unusual or interesting he presses a button that defines a particular moment in time on the video stream. Once the session is over the coach can return to these points of interest and study them from different angles around the court.The video given to the coach is processed via a "visual content algorithm", says Prof O'Connor. "It is a way to take the one-and-a-half hours of content and synthesise it down. The summary presented to the coach is built around the interest points he specified."
This reduces the routine of training, allowing the coach to focus in and analyse very fine elements of play. "The advantage is it is driven by the expert. The coach tells us what is interesting and we redefine the boundary around that," he says.
There is much potential to expand the system, he believes. The next step will probably be to integrate some of the wearable sensor technology being developed by DCU colleague Prof Dermot Diamond to deliver biometric data such as blood pressure, heart rate and metabolic rate.
Clarity's remit is to apply sensor web technologies to two main areas, the environment and personal health including sport. "This is part of the work programme on health in sport."
For this reason, Prof O'Connor has joined with DCU colleagues Prof Niall Moyna and Dr Kieran Moran from the School of Health and Human Performance to see what biometric data is most relevant to improving performance.