Pages: 30-48

Abstract

Nowadays, the study of bones that are compound materials featuring different characteristics in various body parts has been proposed as a novel subject in mechanic engineering and biomechanics. The present study tends to analyze the free vibrations (attainment of natural frequencies) of a specimen of cow fibula (considering the constraints on access to real human bone in Iran). At first, a 3D finite element model of the cow fibula was prepared using CT-scan images (the model is created by MIMICS software) following which the model was transferred to Abaqus Software to be further processed. In the beginning, the characteristics of the bone material is specified in the form of elastic inhomogeneous isotropic (based on density-elasticity relations offered by Carter, Keller and Morgan) (discrete model) and, then, the properties of the materials were inserted in a continuous manner for the individual bone parts following which the natural frequencies were acquired. Next, the effect of both of the models on the vibration attributes of the bone specimen was evaluated and the obtained result were compared with the laboratory results and it was made clear that the approach shift from discrete to continuous provides for obtaining more acceptable results (closeness of the answers to the experimental numbers) and it was found out that Morgan’s relations provide for laboratory results closer to the real data.