Study On Vibration Injury Of Human Lumbar Spine In Tractor Driver Based On Biomechanics

In order to solve the problem that the tractor driver’s lumbar spine is easy to be damaged in vibration environment,a driver tractor biomechanical model and a three-dimensional nonlinear finite element model of the L4-L5 segment of the tractor driver’s lumbar spine were established in this paper.The specific research contents of this paper are as follows:1.Build the vibration test system under the tractor seat,collect and calculate the vibration acceleration of the seat in three directions,get the acceleration power spectrum of the seat in three directions,and analyze the data,and know that the peak acceleration of the seat power spectrum is within 10 Hz,at the same time,provide the frequency range reference for the following study of lumbar spine injury.2.The biomechanical model of driver cab was established,and the s EMG signals of erector spinae and multifidus were collected to verify the accuracy of the biomechanical model.Then,the force characteristics of L4-L5 segment of lumbar spine were calculated based on the reverse dynamics method,which provided load data and boundary conditions for the finite element model simulation of lumbar spine.3.The geometric model of L4-L5 segment of human lumbar spine was constructed,and the mesh generation and material assignment were carried out for the geometric model.The mesh type of vertebrae and intervertebral disc(nucleus pulposus,matrix and endplate)was eight node hexahedron,and the vertebrae and intervertebral disc shared the same node.Then the validity of the finite element model of lumbar spine was verified: by applying the same boundary conditions and loads as the existing literature,The prediction results of lumbar flexion,extension and scoliosis are basically consistent with the experimental results in the literature.4.The L4-L5 finite element model was used to quantitatively study the effects of the driver’s sitting posture and vibration frequency on the vibration injury of the lumbar spine in the field operation;In the case of vibration,the driver’s intervertebral disc suffered from severe compression,which led to the weak posterior annulus fibrosus damaged first.The research results provide a reference for the research of reducing the driver’s lumbar injury and seat active vibration reduction.