THE PREDICITON OF SEAT TRANSMISSIBILITY FROM MEASURES OF SEAT IMPEDANCE

✍ Scribed by L. Wei; J. Griffin

• Publisher: Elsevier Science
• Year: 1998
• Tongue: English
• Weight: 282 KB
• Volume: 214
• Category: Article
• ISSN: 0022-460X
• DOI: 10.1006/jsvi.1998.1540

✦ Synopsis

A method of predicting seat transmissibility from mathematical models of the seat and the human body is described. The complex dynamic stiffness of a seat is determined by measurement using an indenter rig, and its stiffness and damping subsequently determined by curve-fitting. By using the fitted stiffness and damping of the seat model, and a previously determined dynamic model of the human body, the seat transmissibility is predicted mathematically. The method is illustrated with data obtained with a car seat and also a rectangular sample of foam. The seat and foam transmissibilities were predicted over the frequency range 1•25-25 Hz using two alternative models of the human body (a one-degree-of-freedom model and a two-degree-of-freedom model). The predicted seat transmissibilities were close to those measured in a group of eight subjects over the entire frequency range. The two-degree-of-freedom model of the human body provided better predictions where the seat and foam showed a second resonance around 8 Hz. The need for a non-linear mathematical model of the human body and a non-linear seat model is discussed.