Optimisation of non-linear inter-vehicle active suspension control laws applied to railway trains.

Inter-vehicle railway dampers are utilised on high speed railway vehicles to improve passenger ride comfort. Extensive theoretical and analytical assessment of the performance benefits offered by inter-vehicle dampers has not previously been attempted, partly due to the lack. of adequate modelling software and the computational demands involved in analysing the dynamic behaviour of long trains, but also because suspension design in the railway industry has progressed in a rather heuristic and experimental manner. This paper analyses the behaviour of trains containing between three and seven vehicles. It utilises a non-linear simplex search method to evaluate the inter-vehicle spring and damper rates a train should possess for optimal ride quality. It also investigates the effects of non-linear active inter-vehicle connections and comments on the contrasting performance.