Non-linear finite element analysis has been used to investigate the contact problem between a buttock and a cushion of varying properties. The buttock tissue has been modelled on the macroscale by assuming it to be a hyperelastic (rubber-like) material with properties that correspond to the overall buttock response. Both rigid and flexible cushions have been considered. The contact between the cushion and the buttock has been modelled assuming both friction and friction-free conditions. The effect of these parameters on the buttock-cushion deformation and the tissue compressive and shear stress distributions have been presented. This study forms part of work towards the development of body segment simulators for use in investigations of seating and other support surfaces.
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