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A comprehensive comparison between an air-inflated seat cushion designed for truck seats and a commonly used foam cushion is provided, using a single-axis test rig designed for seat dynamic testing. Different types of tests were conducted in order to evaluate various aspects of each type of cushion; in terms of their response to narrowband (single frequency) dynamics, broadband input of the type that is commonly used in the trucking industry for testing seats, and a step input for assessing the damping characteristics of each cushion. The tests were conducted over a twelve-hour period—in four-hour intervals—measuring the changes that occur at the seat cushion over time and assessing how these changes can affect the metrics that are used for evaluating the cushions. The tests indicated a greater stiffening of the foam cushion over time, as compared with the air-inflated cushion that showed almost no change in stiffness when exposed to a static weight for twelve hours.

Two alternative methods are presented for studying the comfort, and possibly fatigue, effects of vehicle seats, in particular truck seats that include a seat suspension. The methods, named “aPcrms” and “SPD%” for the purpose of this study, are based on analyzing the pressure profile at the seat cushion/human body interface in a manner that accounts for the contact area, pressure distribution, and change in contact pressure. The alternative methods are compared with methods suggested in the past for vehicle seats, using a laboratory test rig and a truck seat with a conventional foam cushion and an air-inflated seat cushion. The results show that the proposed methods better highlight the human comfort differences between the two cushion types, and provide objective measures that better correlate with subjective measures from a separate field study on the same types of seats.

This study reports the objective results from a project investigating the effectiveness of several newly proposed metrics to compare fatigue performance between two distinct truck seat cushions, specifically standard foam versus air-inflated cushions. The subjective results from this project have shown the drivers in our study prefer the air-inflated seat cushion over their normal foam cushion, and that air-inflated seat cushions provide advantages in terms of comfort, support, and fatigue [1]. This study aims to further explore the differences between these two different seat cushions by highlighting the differences in objective pressure distribution measurements. Road tests were performed using existing commercial trucks in the daily operations of Averitt Express. A retrofit air-inflated seat cushion was installed in the fleet's trucks, and the drivers were allowed to adjust to the seats over approximately one week.

This study reports the subjective results from a project investigating the effectiveness of several newly proposed metrics to compare fatigue performance between two distinct truck seat cushions, specifically standard foam versus air-inflated cushions. We also highlight some of the fundamental differences between air-inflated and foam seat cushion based on driver's perceptions. Road tests were performed using existing commercial trucks in the daily operations of Averitt Express. A retrofit air-inflated seat cushion was installed in the fleet's trucks, and the drivers were allowed to adjust to the seats over approximately one week. After this adjustment period, twelve drivers rode on both the air-inflated seat cushion and their original foam seat cushion during their regularly scheduled routes. Surveys were collected throughout the test sessions and the truck seats were fitted with instrumentation to capture physical measurements of seat pressure distribution.