August 31 2003 /Wi-Fi Technology News/- Did you ever wonder which route chosen by M?lanie Turgeon (Canada) and Michael Walchhofer (Austria) when they achieved the fastest downhill times at the 2003 Ski Championships in St. Moritz? What was their speed when passing the gates? How did the piste look from the skiers' perspective? More importantly, how could their performance and that of their equipment be improved?
These are questions that Swiss TV broadcaster, SF DRS, the Geodetic Engineering Laboratory of the Swiss Federal Institute of Technology Lausanne (EPFL), and 3D visualisation specialist, Dartfish Corporation, set out to answer when they collaborated on a virtual animation project that would thrill TV viewers around the world.
This exciting project gave TV viewers the unusual possibility to see the piste as the competitors saw it, not by using cumbersome cameras but by accurately tracking each skier using the GPS satellite-based global positioning system. But the real benefit was that it gave the skiers the opportunity to analyse their performance, and it provided the ski vendors the information needed to optimise their equipment.
Following a detailed survey of the ski run using special stereoscopic cameras and GPS surveying techniques, a 3D model was generated to very high accuracy. Simply by knowing the skiers' exact position, the system simulated their changing view of the run as if seen from a virtual camera flying down the mountainside a few metres behind them. The result was a very accurate virtual reality TV film in place of the more familiar action-replay.
The equipment developed by the Geodetic Engineering Laboratory to track each entrant included a GPS antenna attached to the skier's helmet, GPS receiver and additional equipment that transmitted their position to the 3D virtual reality system back at base. The physical and technical demands were very extreme and a special miniature antenna developed by UK-based Sarantel was used during the trials to receive the satellite signals.
Sarantel's ceramic antenna is not only indestructible, but provides other significant benefits in mobile wireless applications, particularly where imperfect conditions are the norm. In this case, not only were the ambient temperature extremely low and the environment hostile to satellite signals reception but also it was vital that the maximum number of GPS satellites is tracked by the receiver at all times. The company's PowerHelix antenna more than adequately demonstrated its ability to receive the very weak GPS signals from satellites low down on the horizon, even when the skiers had their heads inclined horizontally.
As well as enhancing the TV viewers' enjoyment, this GPS-based simulation and analysis is now available to be used by racers and equipment manufacturers to optimise performance on a run-by-run basis.
For more information about Sarantel, visit their web site at: http://www.sarantel.com
|
