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Active suspension in trains, phase II

Published Jan 10, 2013


Sources of funding

·         KTH Railway Group

·         KTH Rail Vehicle


High speed trains are becoming an essential part of railway passenger transportation. Higher speed means higher level of vibration which can result in poor ride comfort. To deal with this problem either track quality should be improved or vehicle suspension should be modified. Modifying track quality can be quite time and money consuming; therefore many studies are focused on modifying secondary suspension.

In a previous study at KTH by Anneli Orvnäs active lateral actuators and hold off device were developed and implemented for the secondary suspension. Active vertical actuators were investigated as well but not implemented.


The objective of this project is to further develop active vertical actuators and keep the previously developed lateral actuators and hold off device for maintaining or even improving the ride comfort either for increased speed from 200 to 250 or for a track with inferior quality.

Research direction

Focus in this project will be on secondary suspension system where it will be tried to improve ride comfort by using active vertical actuators instead of passive conventional dampers. To achieve a successful active suspension it is necessary to find the right control strategy for controlling actuators and also appropriate actuators. It is important to make sure that the implemented design is safe, reliable and at the same time cost-efficient.

The active vertical suspension will be developed in close co-operation with Bombardier. Computer simulations with SIMPACK (MBS software) together with SIMULINK will be done to design the controller and then measurements will be done on a two-car Regina train to evaluate the performance of the design.

Page responsible:Mats Berg
Belongs to: Rail Vehicles
Last changed: Jan 10, 2013