Study On Random Vibration Response Of Lumbar Spine Of Vehicle Occupant

With the number of car increasing recent years, more and more people pay attention on cars’ comfortable and vehicle occupants’ healthy. Because of engine and road rough, every people who sitting in a moving car will expose on the environment of vibration, most of these people suffer from the lumbar diseases like low back pain. For researching the connection of lumbar diseases and vehicle vibration environment, it is necessary to study the mechanics condition of vehicle occupants’ lumbar. This essay mainly do some researches on static and dynamic properties of human spine under vehicle environment by finite element method integrate with bio-mechanics theory, these results will provide some reference on the health of human spine in vehicle vibration environment.Firstly, build a complete T12-Pelvis finite element model by CT, Mimics and Ansys; make some static analysis in each segment and the whole model. To ensure the validation of the finite element model, the analysis results are compared with experiment data. In addition, the validation methods of similar human spine models are classified and summarized.Secondly, use static analysis module in Workbench to do static analysis of T12-L1 segments and T12-Pelivis FEM under four different sitting positions. These sitting positions include upright, forward bending unidirectional lateral bending and axial bending. The static mechanics condition of T12-Pelivis can be researched by the data of displacement and stress.Again, use dynamic analysis module in Workbench to do modal analysis of whole T12-Pelvis model. Extract the natural frequencies of spinal for initial 20 orders and former six order mode shape of T12-Pelvis. Moreover, this part study the influence of anteroposterior (A-P) shifting of trunk mass from the upright sedentary posture on dynamic characteristics of the human lumbar spine.Finally, in the basis of modal analysis, the last part study lumbar dynamic response to random vibration, which take road rough PSD (in vertical displacement) as input signal. The dynamic response results include sensitive frequency, vibration curve of stress and displacement. These results can provide a reference on the design of car seats about vibration reduction.