Challenge

Week-7 Head Impact

MMukesh Kumar Baraik9 Dec 2022

AIM

Pedestrian Head Impact

OBJECTIVE

Creating RIGIDWALL Keyword.
Head Impact test.
Calculating HIC.

THEORY

Pedestrian protect CAE is a part of vehicle safety engineering from crash perspective in pedestrian protection, we look for imparting minimum injury to head, upper leg, lower leg in case of an accident with human subject.

HIC: It is a acronym of Head Injury Criterion. It is a measure of the likelihood of head injury arising from impact The HIC can be used to assess safety related to vehicle, personal protective gear, and sport equipment.

The formula for HIC is

Where t₁&t₂ are the initial and final times in seconds.

PROCEDURE

CASE:1 Simple head is impact with Rigidwall

Creation of Rigidwall: A RIGIDWALL is created for impact with head.

MODEL < CREENT < RIGIDWALL < CREATE

Include: This keyword provides collecting different ls dyna files in one file.

MODEL < KEYWORD < INCLUDE < TRANSFORMATION

Section: In this HEAD is defined as SHELL section.

MODEL < KEYWORD < SECTION < SHELL

Material: In this material of head is defined. For head elastic material is considered.

MODEL < KEYWORD < MAT < 001-ELASTIC

Part: In this both section and material is connect .

MODEL < KEYWORD < PART

Motion: For movement of the head initial velocity card is defined.While defining velocity node set is first defined with all node of human head mesh.

MODEL < CREENT < SET_NODE

MODEL < KEYWORD < INITIAL < VELOCITY

Termination: In this time is set for termination the simulation.

MODEL < KEYWORD < CONTROL < TERMINATION

Output file: In this different output file is provided.

MODEL < KEYWORD < DATABASE < ASCII

MODEL < KEYWORD < DATABASE < BINARY D3PLOT

CASE:2 Headform is impact with Rigidwall

In this simulation all the process and procedures are same however in place of simple head complicated modellled head is used.

CASE:3 Headform is impact with Hood.

Include: This keyword provides collecting different ls dyna files in one file.

First head model is included in this file through *INCLUDE. For including first, we have to transform a include file for which transform keyword is defined from define.

MODEL < KEYWORD < DEFINE < TRANSFORMATION

MODEL < KEYWORD < INCLUDE < TRANSFORMATION

Section: In this Hood is defined as SHELL section.

MODEL < KEYWORD < SECTION < SHELL

Material: In this material of hood is defined. For head Peacewise Linear plasticity material is considered.

MODEL < KEYWORD < MAT < 024- PEACEWISE LINEAR PLASTICITY MATERIAL

Part: In this both section and material is connect .

MODEL < KEYWORD < PART

Contact: In this section contact between hood and head skin is defined.

MODEL < KEYWORD < CONTACT < AUTOMATIC SURFACE TO SURFACE

Motion: For movement of the head initial velocity card is defined. While defining velocity node set is first defined with all node of human head mesh.

MODEL < CREENT < SET_NODE