A hi-tech tennis coach at courtside
Tennis equipment has come a long way since the days of the simple wooden racquet with catgut strings.
Metal and then carbon models appeared on the market, and now computer technology is being embedded in one of the newer tennis racquets on the market.
Packed with sensors detecting string vibration and movement, the device works with a smartphone (over Bluetooth) or plugs into a computer (via USB).
But this tech revolution has also led the International Tennis Federation to change its rulebook, and to introduce a programme to approve the new equipment for use in its tournaments.
The BBC has been behind the scenes at tennis laboratories to see what is involved. LJ Rich reports.