Trambus systems are encountering a renewed interest since they represent an interesting trade off between the sustainability of battery-operated trams under partially electrified lines, and the service flexibility of conventional buses. Thanks to the cooperation between University of Florence and ENEA, authors have designed a system to allow the current collection of electric buses under catenary systems conventionally used by tramways. With the proposed current collection technology, tramway and Trambus systems can share the same power infrastructure allowing a complete integration of these different transportation technologies. In this work attention is focused on the design of the current collection system and on the innovative suspension arm that assure the return of the current on a ground/return rail.