Determining the firmness of a pear using finite element modal analysis

In this paper, the variation of the dynamic characteristics of a pear (Conference type) due to changes in material characteristics is investigated using finite element simulations. An image processing techniques has been used to obtain the geometrical model of a Conference pear. The dynamic behaviour of this type of pear and the correlation of its behaviour with material characteristics has been investigated by using a numerical modal analysis. From these results, it was concluded that the Young's modulus of the spherical calyx end of the pear could be determined from the oblate-prolate modes and that the Young's modulus of the stem end of the pear could be determined from the first bending modes. The firmness of the spherical calyx end of the pear can be determined analogous to a spherical fruit. A finite element analysis using a conical model for the stem end of the pear indicated that a similar formula for the firmness of the stem end of the pear can be derived. (C) 1999 Silsoe Research Institute.