Abstract: Aiming at the problem of surface reconstruction existed in the customized design
of shoe last for the fitness and comfort, the paper presents an algorithm and its realization of
parameterized reconstruction of shoe last surface based on the transformation of cross section of
plantar girth and instep girth. The cross section curve of plantar girth and instep girth are
transformed to the customized effect through the control of the circumference and height of
plantar girth and instep girth. The partial and global spread functions are constructed based on
cubic spline interpolation function to realize the spreading of the two girth cross section
transformation to the whole shoe last surface in two ways. The algorithm realizes the accurate
modification of the shoe last circumference, with the surface smoothness maintained. Having been
programmed with MATLAB, it is used to assist shoe last surface reconstruction in a visualized
interactive way, with the interface being simple and fast to operate.

Key words: shoe last surface reconstruction, plantar girth and instep girth, cross section
transformation, spread function, visualized and interactive design