Tilting trains and beyond - the future for active railway suspensions: Part 2 Improving stability and guidance

Active components are starting to become accepted within railway vehicle suspension systems which have been exclusively mechanical since railways began in the 1800s. At the moment these are principally being applied in tilting trains, but opportunities which arise from applying control systems engineering to railway suspensions extend much further, and this is the second of two articles (the first was in August 1999 CCEJ) which explore these possibilities. Part 2 deals with control approaches which can be applied at a fundamental level to influence the way in which the wheels and wheelsets function in terms of guidance and stability. A range of options are explained, and then some ideas are presented giving a possible vision of future 'mechatronic' rail vehicles.