The dynamic response of a subject seated on various cushions

An impact pendulum was used to examine the dynamic response of the seated subject. The dynamic response is of interest in establishing the relationship between driving and low-back pain. Accelerometers were placed on the seat and in vivo at the L3 vertebra. The transmissibility and phase angle were obtained in the frequency domain for a variety of cushions. Soft cushions were found to increase the gain at the first natural frequency.