In Japan a delay of five minutes would be a scandal, said two articles in the Orange and the WiWovor not so long ago. And indeed, one can look a little jealous of the futuristic concepts. Lived mobility of tomorrow? And what about Europe? What are the pitfalls on the way to sustainable mobility over long distances?
Well, at least between the first rides of the “Adler” between Nuremberg and Fürth and the current ICE 4, the technology developed breathtakingly. However, the basic principle of rail and wheel sets with flanges has remained with us in Europe to this day. And it’s one of the big drawbacks that often makes driving on the train a noisy, uncomfortable experience. But at a time when public transport is one of the main pillars of the mobility shift, this principle needs to be put to the test.
There are different approaches. Certainly the most radical is the Hyperloop technology promoted by Tesla boss Elon Musk. Here, the train moves in a tube and on magnetic rails, so that car and rail do not touch. A partial vacuum in the tube allows very high speeds; the record currently stands – held by the team of the Technical University of Munich – at 467 km / h.
However, the Hyperloop is still quite far removed from its real implementation. More realistic are current developments that run on conventional rails and still increase ride comfort and achievable speeds. One example is the project “Next Generation Train” (NGT) of the German Aerospace Center (DLR), which aims to offer completely new driving dynamics with electrically driven and steered single wheels.
Simulation and virtual test drives make a decisive contribution to the fact that more people leave their cars and thus make an important contribution to climate protection.
The NGT is a two-story high-speed train; the middle cars do not have the usual bogies with two axles, but four single wheels. Depending on a pair of individual wheels hangs in its own chassis, which requires an electronic control of these wheels. One wheelset is automatically centered inside the two rails, with single wheels the track width has to be regulated. On the other hand, such wheels do not screech when driving over tight track curves and the suspension can be better regulated, which increases ride comfort.
At the same time, each wheel is equipped with a 260 kW drive motor, which is directly coupled to the wheel. The traction motors also act as actuators for active tracking and radial steering. The railway specialists of DLR simulated the new chassis configuration with Simpack.
It was found that with an active control of the guidance – which centers the car only on different acceleration of the two wheels of an axle on the rail – the car can be kept much more accurate in the lane, not only in a comfort gain, but also more than 50 percent less wear on the wheel results. Even at a speed of 400 km / h, the NGT achieved a very high level of comfort, which improved depending on the seating position in the car up to 25 percent compared to today’s high-speed vehicles.
Current research focuses on a sensor that can reliably detect the position of a wheel relative to the rail under the very tough everyday conditions of rail transport and thus provides the input for the mechatronic tracking. The DLR is confident that this sensor can be developed in the near future. In any case, Simpack’s extensive simulations have not only proven that the idea of independent wheel control is right, but also provided valuable implementation tips that are just entering a new phase with the construction of an M1: 1 prototype of this suspension by 2022.
Simulation and virtual test drives make a decisive contribution to the fact that more people leave their cars and thus make an important contribution to climate protection. In any case, the lack of comfort and typical rattling on the train will soon no longer be an excuse. The train of the future does not rattle, it shoots at 400 km / h like a flying carpet over the track and is thus a real alternative for long stretches. Not only based on the individual traffic by car, but also in comparison or as a supplement to air traffic. Not only does transport move closer together, but mobility also has a real chance of becoming more sustainable overall.