An Analog Simulation Study On The Comfort Of Air-inflated Seat Cushions Of Heavy Trucks

With the development of people's living standard, automobiles have been more and more widely used. At the same time, requirements for automobiles are getting higher and higher. Being safe, comfortable and convenient is the optimal objective for the design of modern seat. As one of the most important parts of an automobile, seat is a significant element that connects passengers and driver with the body of the automobile, which is directly related to the comfort and security of passengers. The ROHO Group of the US has developed air-inflated seat cushions which effectively reduce the vibration transmission in perpendicular direction and improve the seating comfort of drivers. This technology was initially applied to wheelchairs so as to improve the quality of life of those patients sitting on wheelchairs for a long time, and later was widely applied to seats of automobiles.Long distance and heavy load are two characteristics of heavy trucks, which often results in drivers' fatigue, then traffic accidents. This thesis suggests that drivers of heavy trucks use air-inflated seat cushions in order to improve the comfort performance in long distance driving and reduce the possibility of accidents.On the basis of physical performance of air-inflated seat cushions and using the software of visual studio, .net 2005 and C# language, this thesis creates a mathematical model for air-inflated seat cushion system and studies the seating comfort of drivers with parameters set up by Daihatsu. In former studies, the assessment method of objective physical quantity, not quantitative analysis, was adopted to study the comfort performance of seating cushions; in order to carry out a better study, Pressure Change Rate Root Mean Square (Pcrms) value is adopted in this thesis to assess the seating comfort performance. When the Pcrms value decreases, comfort performance will increase.In this thesis, a model is created with the software of visual studio, and .net 2005 to find out the relationship between seated area, cell height, outlet area, material stiffness, driver's weight and the Perms value, and how different weights affect the relationship between these parameters and the Perms value. With analyses on these relationships and according to the principle that when the Perms value decreases, the comfort performance will increase, effects of different parameters on comfort performance are found out.