Abstract: The full-contact insole can reduce the peak plantar pressure to improve and prevent neurotic ulcer symptoms in diabetic foot. The traditional full-contact insole design method is complex to operate. In this paper, a novel 3D printing modeling method for full-contact insole is proposed based on triply periodic minimal surface （TPMS）. Through three steps of data collection, full-contact model construction and model porousness, a full-contact insole based on TPMS structure is constructed and produced using 3D printing technology. First, the user foot model and the scan insole model are collected. Then the lower boundary of the pre-designed insole model is approximated to the scan insole model by Laplace transform algorithm, and the full-contact insole model is constructed by adjusting the upper surface of the pre-designed insole model to the bottom of foot. Finally, the Marching Cubes mesh reconstruction method is applied to reconstruct the full-contact insole into a TPMS structure based mesh model. The experiment verifies that the method proposed in this paper can design a full-contact insole with the ability to reduce the peak pressure of the sole.

Key words: triply periodic minimal surface, full-contact insole, 3D printing, 3D modeling