Introduction to Capstone Team Project Semester: Name of Project: Coordinator: Supervisor: Jury Member: Submitted by:
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Traumatic brain injury (TBI) is known as the most important reason for human fatalities in car accidents. Many studies have been performed to understand the structure and mechanisms of head and brain injuries. By the development of computer science in engineering, new numerical-based methods have been time in this thesis that can be considered as the novelty of the present work. In order to validate the model, the obtained results from the pressure analysis of brain were compared with the published experimental results and a good correlation was witnessed between them.
Head and brain injuries are one of the most important causes of fatalities. There are over 2 million traumatic brain injury victims each year which causes 140000 deaths every year .
changing just after death, but it still has the closest properties to a live human body.
By development of computers in engineering science, new methods emerged that eased the way of researchers to perform their analysis. Finite Element Method (FEM) is the offspring of computer usage in engineering and is one of the mostly used tools for modeling the behavior of materials and bodies under the influence of any stimulus. FEM is a numerical method that converts Partial Differential Equations (PDE) into simpler linear equations by dividing a complex geometry into small elements and applies calculus variation methods and minimizes the errors by iterations and gives an approximate result. This method is especially useful for solving PDEs which are impossible to solve by analytical methods in complex geometries.
1.2 Anatomy of Human head
For a better understanding of the outcome of the research it crucial to have a good knowledge in the anatomy of human’s head and brain………………..
In a head trauma various parts may be involved. Scalp, skull, meninges and the brain itself are of the structures that can be affected and injured. It should be noted that in a severe brain injury it might not necessarily be distinguished in scalp or skin, and vice versa, an extensive damage to skull may be uphold without a significant damage to the brain.
1.3.1 Head Impact
Newman et al [Jam00] presented a new criterion called head impact power (HIP) to
A biomechanical model can be used wherever there is a need to examine musculoskeletal methods and compared with experimental methods. In this chapter, biomechanical studies about the response of skull and brain to frontal impact collisions with various directions are explained.
A human head model consists of several parts. In order to achieve better and more
to each other by nodes. As a result there is a relation between each element by these nodes solutions for them. Many computer programs and softwares have been developed to solve problems and complicated equations obtained from various fields of studies such as structural tests in civil engineering, fluid mechanic analysis and biomechanics.
Finite element analysis on human’s head performed earlier in 1973 by Hardy [Har73] for the first time and it was then improved a year after by Nickell [Nic74]. The human’s head model consisted of a skull and brain only and other parts inside of the skull were neglected. The model was very simple and contained only 23 nodes. The data collected from their research was concluded that a 3500 lbs. load on front and 1400 lbs. on the sides of the head are the amount of load that triggers the first cracks on the skull. In 1975, Shugar improved Hardy’s model and took the brain into the consideration as a fluid and faced a great deal of improvement in the results in comparison with Hardy and Marcals study. The details in the 3D model of head significantly improved by Horsey in 1981. Skull bones, spinal cord, brain and cerebrospinal fluid space
2.3 Experimental Studies
The validity of analytical data is determined by comparing it with experimental data.
DESIGN AND ANALYSIS
Many studies on human head are mainly focused on the head influenced by stresses. The stimulus can be linear and rotational acceleration, impacts or loads, and the effects of these stresses are generally obtained by experimental, analytical and