Abstract
Conventional mattresses can not adjust precisely according to the individualized spinal alignment. In addition, there is no theoretical basis for quantitative design and adjustment of mattresses firmness. The purpose of this paper is to overcome deficiency of traditional air chambers for research of ergonomic mattresses in accordance with spinal alignment. A novel variable stiffness air spring was designed and static experiments were conducted to analyze its mechanical properties and its influence factors. An analytical model based on geometric parameters and initial internal pressure was established. The results showed that the air spring has nonlinear stiffness during the working process. Furthermore, the model can predict the load of the air spring accurately at any equilibrium position with an average error of 6.96%. The initial stiffness, volume and assembly height could be predicted by means of geometric parameters and initial internal pressure. The conclusions are that the novel air spring can obtain predictable stiffness compared with cubic and the rod-shaped air chambers, which provides a theoretical basis and possible solution for the study of stiffness adaptive ergonomic mattress according to spinal alignment.
Highlights
It is generally accepted that there are many effects of mattresses on sleep comfort and health, such as thermal comfort [1,2] and supportive comfort that directly affect sleep quality, physiological and mental health
The main function of mattresses is to support human body, allowing muscles and spinal discs to recover from sustained loading by providing reasonable pressure distribution in humanmattress interface and spinal alignment [3], which is greatly influenced by the firmness of mattresses [4,5], individual anthropometric parameters [6,7]
In order to describe the variable stiffness of various air springs in general, an analytical model based on geometric parameters and initial pressure is needed to predict the stiffness of any position
Summary
It is generally accepted that there are many effects of mattresses on sleep comfort and health, such as thermal comfort [1,2] and supportive comfort that directly affect sleep quality, physiological and mental health. The main function of mattresses is to support human body, allowing muscles and spinal discs to recover from sustained loading by providing reasonable pressure distribution in humanmattress interface and spinal alignment [3], which is greatly influenced by the firmness of mattresses [4,5], individual anthropometric parameters [6,7]. Depending on spinal alignment and pressure distribution of humanmattress interface [8], the ideal mattress should be positively adapted to the changes in lying postures and human dimensions. This is an urgent need, but still a challenge. An active depressurization air mattress quantitatively measured body pressure distribution of human-mattress interface and successfully adjusted firmness of mattress by means of Time-of-Flight optical
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
