Effect of Operator Seat Design on Vibration Exposure

Abstract

A field study was conducted at a large metropolitan subway system to determine vibration attenuation characteristics of train operator seats through a comparative method. To compare operator seats, vibration measurements were made under conditions for which all variables other than the operator seat were constant. This was achieved by carrying out the vibration measurements on a single subway line, using a single train with constant composition throughout the data collection, with a single train operator and using the same operator schedule. The study was carried out in accordance with the measurement and evaluation techniques outlined in the ISO 2631 standard on whole-body vibration developed by the International Organization for Standardization. The results obtained were analyzed to assess the effectiveness of each seat in reducing the mechanical vibrations transmitted to train operators. Results revealed that seats with complex designs and advanced features transmitted 5% and 19% more overall vibration levels to the train operators than those seats with relatively simple designs, the reasons for which could be explained through simple structural and kinematic analysis.