A LABORATORY TEST BENCH TO SUPPORT PASSENGER COMFORT ASSESSMENT IN RAILWAY VEHICLES

Ride comfort is assuming increasing importance for railway industry, from the very first stage of vehicle design up to the final on track tests. Reference standards define the measuring positions and the data processing techniques to experimentally assess ride comfort. The EN 12299 standard defines the NMV as the reference index for evaluating mean comfort, starting from acceleration measurements taken on the vehicle floor. However, passenger's perception is also influenced by the dynamic response of the seat, and by the consequent vibration levels at the interface with the human body. For this reason, additional indexes such as the NVA proposed by EN 12299 can be adopted. This paper presents a laboratory test bench which has been set up for investigating the relationship between the floor vibration and the actual comfort of a seated passenger. The test bench consists in a portion of floating floor on which a pair of seats is installed. The system is excited through an electro-hydraulic actuator and acceleration signals are collected in different positions, also including passenger-seat interface. The test bench can be used for analysing the effect of seat dynamics on passenger comfort and for supporting seat design optimization.