Current radial bogies also have pivoting axles, but they pivot passively. Controlling the pivot would mean the bogies retain stiffness on straight track, allowing higher speed on straights while retaining the curve benefits of today's radial bogies.

The active bogie is part of the "Green Train" project, where Bombardier is working with the Royal Swedish Insitute of Technology (KTH) and Swedish Rail Administration Banverket on a next-generation X�2000 train for 250 km/h. A modified Regina train is being tested with private operator T�gkompaniet next summer.

The aim of the proposed program Green Train is to strengthen the Swedish competence in developing and procuring the future generation of high-speed trains, according to Swedish requirements and special conditions. The aim is also to strengthen possibilities to participate in and influence the all-European program of railway research and standardisation.

This is to be achieved by a joint R&D program between The Swedish National Rail Administration, Banverket, and the Swedish rail industry on one hand and Swedish universities, research institutes and consultants on the other.

Work package 1 aims at developing track-friendly bogies with a high ride and acoustic comfort for speeds of at least 250 km/h, train-borne noise barriers and active lateral suspension. Also behaviour under winter conditions should be tested.