Posted to News on 24th Apr 2020, 00:00
Linear guides used to project "mark to jump" onto sand for spectators
In athletics, some disciplines are difficult to follow for spectators. For football, it is clear to see when the ball is in the goal. In long jump, however, it is it is not easy to judge whether the last jump has set a new record. Virtual lines help the TV audience but they are not visible to spectators in the stadium. The PrimeLine system, developed by Golden Fly Sports, solves this problem by projecting the ‘mark to jump’ onto the sand.
The mobile installation was devised by Armin Margreiter, the former national coach of the Austrian long jump team, in cooperation with the laser projection specialist MediaLas. The system consists of three laser diodes, which are aimed at the pit and produce a visible line even in direct sunlight. The developers needed a drive unit that could move the lasers along a range of distances from 3 to 12 metres.
In the design of the system, the challenging environmental considerations were key. Long jumpers tend to kick up a lot of sand upon landing, which can bind with lubricants used in a conventional linear guide system causing it to stick. The development team had set the bar very high: all the components had to be robust and, above all, resistant to sand while being lightweight.
Therefore, instead of traditional metal bearings, linear bearings made of the lubrication-free, high-performance polymer iglidur J200 from Igus were selected.
These linear guides are based on the principle of ‘gliding instead of rolling’, with the corrosion-free, tribo-optimised iglidur polymers used as a sliding surface. Maintenance-free, drylin linear guides are insensitive to influences such as dirt, water, chemicals, heat or impacts. In addition, they have a very low noise because of the materials used and the special design.
With these properties, drylin linear guides can be used in a wide variety of environments, including extreme ones. The modular system allows for high flexibility with different rail guides and pillow blocks.
All of this was key for the PrimeLine system. As the bearing remains dry, sand does not adhere and damage it. Its low coefficient of friction allows the precise positioning required by the IAAF, the International Association of Athletics Federation.
As well as being corrosion resistant and maintenance free, the drylin linear guide is also has a long service life, which can be calculated online. As a result, it can be used continuously even during long competitions. Armin Margreiter is convinced by the quality of Igus products: “The linear guides from Igus have been in use on my systems for four years and they have never posed the slightest problem.”
The system has proven itself at the Golden Roof Challenge for which Margreiter is the Meet Director. His dream was to bring athletics to the heart of some of the world’s most beautiful cities and deliver attractive elite sports events to the public. The Golden Fly series does just that, with the world’s first ever in-city athletics tour. Along with Innsbruck, Austria (pictured), tour stops in recent years have included Schaan in Liechtenstein, Rio de Janeiro in Brazil, Munich in Germany, Salzburg in Austria, and Munich in Germany.
