Structure and properties of composite seat with auxetic springs

Scientific investigations of structures characterised by auxetic properties conducted so far have led to analyses on a molecular and macroscopic scale and few studies have been concerned with descriptions of auxetic models which could find application in objects of everyday use. The aim of this paper was to carry out numerical modelling and physical verification of furniture seat quality made up of auxetic pressure springs. The authors decided to determine system stiffness and distribution of contact pressure on their surface. The performed detailed numerical analysis made it possible to evaluate the comfort of seat utilisation as well as to assess the impact of seat modification with NHE35 foam on changes of this comfort. In addition, it was demonstrated that numerical modelling may provide a useful tool for rapid prototyping of complex, multilayer systems manufactured from materials with non-linear characteristics. Results of numerical calculations were verified in the laboratory determining the scale of errors with which these results should be interpreted.