Get on board for the future – with fully automatic wire contacting and disconnection guidance for trolleybus poles!

With LibroDuct, trolleybuses can travel shorter or longer stretches of their routes without overhead wires. With flexible recharging, stationary periods don’t become bottlenecks in operational planning, as is the case with recharging at isolated charging points

Inception and context

Even though everyone’s talking about electric buses nowadays, conventional battery and fuel cells or hybrid buses bring too many limitations with them in terms of capacity, range, maturity, or travel convenience, or they’re considered a transitional technology. Currently, trolleybuses alone represent a technology that could completely replace municipal diesel buses, at least from a technical standpoint. That they haven’t done so comes down to two main reasons: the cost and acceptance of their infrastructure (especially the overhead wires), and their lack of flexibility due to dependence on overhead wires and routing. Another reason often cited is that the vehicles cost more in comparison to diesel buses, but this is unfounded, since the cost of acquisition is offset by longer lifecycles and lower energy and maintenance costs. Moreover, with the purchase of higher quantities of trolleybuses we can expect their price to fall significantly, boosting their cost-effectiveness even more.

LibroDuct: the perfect piece that completes the puzzle

After all there are mass-produced hybrid trolleybuses with battery support by now, so that longer sections of bus lines may be travelled without overhead wires. When reaching the overhead wires again, the task of recontacting them automatically has never been solved satisfactorily. It is precisely this missing piece of the operation that LibroDuct performs.

The goal: universally available e-mobility in municipal public transit systems

E-mobility in municipal public transit is already technically and economically feasible today, and not only in special cases and pilot projects, but everywhere: Where people can live with the limitations of purely battery-powered buses, they will use them. Where there is hydrogen as a side-product or waste product, fuel cell buses will possibly make sense, and for the rest of the cases, especially for long or high-frequency lines or where the topography is challenging, (hybrid) trolleybuses with LibroDuct technology offer the best solution.

The basic idea

The impetus for the development of the LibroDuct technology arose from considerations about which type of electric bus would most likely yield the greatest ecological effect. It is doubtless the (hybrid) trolleybus, since – when driving in contact with overhead wires – there is no conversion loss (battery charging and discharge), plus the battery needs minimal capacity and thus requires less space, weight, and resource consumption for its manufacture. If the described problems with the trolleybus were solved, there would be nothing else to stand in the way of a grand renaissance for this proven means of transportation which is still widely used in many parts of the world. The mission, then, was to automate the process of maneuvering current collector poles to contact the wires and disconnect them again. Until now, the manual and hardware-based systems for contacting wires have been unsatisfactory in many respects, a situation which led to the idea of automating the process using software techniques. The DIaLOGIKa company took on this challenge, and since 2018 its spin-off LibroDuct has been developing it further. Following an intensive search and consideration of the pros and cons of various approaches, a process using optical pattern recognition turned out to be the most favorable. Thus the idea for LibroDuct was born.

Our partners

For the implementation DIaLOGIKa was able to win over Kummler+Matter AG, at that time a member of the Swiss electric services concern Alpiq, as a cooperation partner, a company which has a great deal of experience in the area of e-mobility generally (e.g. as the main contractor for the electrification of the new Gotthard base tunnel) and in current collector systems for trolleybuses, specifically. Meanwhile, further development has been consolidated within LibroDuct GmbH & Co. KG, which has acquired all rights and work results from its partners, and – with its company headquarters located in the DIaLOGIKa building – can continue to make full use of its tried and tested development team, well-equipped testing grounds, and other resources.

Have we got you interested?

Your Contact Partner

Bernhard Schaaf-Christmann

Head of Development, LibroDuct

+49 6897 935-209

+49 6897 935-100

Email us at or call us at +49 (6897) 935-0

You’re interested in LibroDuct? Or you want to integrate LibroDuct into your product?
Talk to us! We’d be happy to hear from you.