Force Prediction of Composite-coated Needle Moving Inside Tissues

Abstract

This research investigates the effectiveness of a composite coating consisting of Polydopamine (PDA), Polytetrafluoroethylene (PTFE), and Activated Carbon (C) to mitigate the potentially harmful effects of needle insertion forces. By evaluating the forces at the interface between the needle and tissue, this study aims to develop a model incorporating experimental and numerical approaches to better understand the mechanics of interfacial forces during coated needle insertion. The proposed model is divided into two components: frictional forces on the needle shaft, modeled using a modified Karnopp model with an elastic force component and cutting forces on the needle tip, modeled using a constant cutting coefficient for a given tissue and insertion speed. Upon testing the model on bovine kidney tissue with a 35mm insertion depth, the results demonstrate that the difference between experimental and modeled insertion forces is in the range of 6.5-17.1% for bare and coated needle. Notably, this difference in the insertion force model is expected when working with real tissues, which possess highly complex structures.