The first Flexity tramways recently entered into service in Zurich’s public transit system (VBZ). A striking feature on the front of the new vehicles is the multicolored, high-resolution LED destination display board – the successful outcome of an international development project over several years by the Luminator Technology Group in Switzerland, Germany and Sweden. The digital tram displays meet all the criteria for roller blind displays and have been approved for rail transport in Europe.

Dynamic LED displays replace roller blinds

Highest color-fastness, graphic diversity, simplest control and handling – the new LED train destination display in a format of 128 x128 pixels meets the highest demands. For VBZ, this means that all desired line colors are displayed on the vehicles in true color. It enables even color tones that could only be inadequately displayed with the then available LED technology. Thanks to the improved graphics capability (resolution), the special legibility requirements of visually impaired persons have also been satisfied. Additional advantages of digitization: thanks to the software integration, routes or stopping points can be easily changed at any time. This means there is no need to remove or replace roller blinds.

International expertise creates innovations

The Luminator engineers have developed completely new, seamless LED arrays with brightness control and numerous diagnostic functions. A major challenge was to accommodate the high packing density of the electronic assemblies in extremely compact external dimensions, while complying with the strict EMC limits and vibration-resistance specifications. The dissipation of waste heat from the LED modules also called for special solutions, as 16 LEDs are accommodated on 1 cm² and the overall depth is just 60 mm.

No less than three European locations of the Luminator Technology Group were involved in the innovation development. The project management of the various trades was carried out from Gossau (Switzerland). Herrljunga (Sweden) was responsible for the hardware and software of the RGB LED module assemblies. Assembly and testing of the prototypes for series production took place in the company's own prototype shop in Rastatt (Germany).

Picture: Flexity tram in Zurich on the road with innovative Luminator display technology.