Search Results

Most methods of vibration analysis focus on measuring the level of vibration. Some methods like ISO-2631 weigh vibration level based on human sensitivity of location, direction, and frequency. Sound can be similarly measured by sound pressure level in dB. It may also be weighted to human frequency sensitivity such as dBA but sound and noise analysis has progressed to measure sound quality. The characteristic and the nature of the sound is studied; for example equal or near equal sound levels can provide different experiences to the listener. Such is the question for vibration; can vibration quality be assessed just as sound quality is assessed? Early on in our studies, vibration sensory experts found a difference in 4 seats yet no objective measurement of vibration level could reliably confirm the sensory experience. Still these particular experiences correlated to certain verbal descriptors including smoothness/roughness.

Experience tells us that one can develop a technically comfortable seat where the seat fits and supports the occupant. The pressure distribution is optimized and the seat and packaging are such that a good posture is attainable by many. The dynamic characteristics of the seat and the vehicle are technically good. Despite all this the customer is not satisfied. Despite it being a technically comfortable seat, it does meet the customers' expectations and/or priorities and thus the comfort provided is lacking. This paper seeks to explore that gap between the seat and the user by modeling comfort using techniques similar to those found in the social sciences where models often focus on user or individual behavior. The model is built upon but diverges from the Cobb Douglas consumer utility model found in economics. It is presented as theory and presents a very different perspective on comfort.

This study identifies and weights statistically significant factors within the J.D. Power and Associates APEAL survey that directly influence the customers' ratings for the vehicle seating system and driver's seat comfort. Three regressions were completed using mean model data from the 2003 Wave 2 J.D. Power and Associates APEAL survey. The first regression uses only seat specific characteristics. The second furthers the first seeking the customer's voice on the complete seating system but includes additional non-seat specific factors. The final regression studies driver's comfort while considering the same non seat specific factors from the J.D. Power and Associates APEAL survey. It concludes with multiple prediction or simulation equations. The APEAL method is unknown to the author and confidential to J.D. Power and Associates.