Safety Analysis And Driver Injury Research Of Rear-mounted Collision Mower

The rapid development of modern lawn operations puts forward higher requirements on the safety performance of the lawn mower.Research and optimize the crashworthiness of the mount lawn mower from the perspective of improving the Rollover Protective Structure(ROPS),so as to better protect the driver.First,based on the analysis of the rearward turning process of the riding lawnmower,a theoretical model of the rearward turning of the riding lawnmower without a driver is established,and the critical working condition of the rearward turning of the riding lawnmower is obtained.The analysis of the change of the roll axis in the middle determines the changes of the angular velocity,kinetic energy and other variables.At the same time,the back-turning finite element model of the driverless lawn mower was constructed,and the results of the back-turning finite element model were compared with the results of the back-turning theoretical model to verify the back-turning finite element model of the mount-type lawn mower effectiveness.Secondly,the driver dummy model was added to the rearward-turning finite element model of the riding lawn mower,and the driver restraint system model was established according to the FMVSS208 regulations.Add two-point seat belts and three-point seat belts to the driver respectively,analyze the dynamic response of the driver under the restraint of the two seat belts during the rollback process,and predict the degree of driver injury under the restraint of the two seat belts.According to the occupant injury mechanism and injury evaluation rules,the driver 's injury is analyzed.The results show that the two-point seat belt cannot effectively protect the driver 's neck,while the three-point seat belt can reduce the driver 's neck by reducing The axial tensile force on the neck achieves effective protection of the driver's neck;the acceleration of the dummy's head under the protection of the two seat belts at 3ms is higher than the safety threshold,and the ROPS of the riding lawnmower has a large deformation,which requires Improve and optimize the safety of mount lawn mowers.Finally,in order to improve the crashworthiness of the ROPS of the mount lawn mower,optimization schemes were proposed from the three angles of increasing the strength,rigidity and energy absorption device of the ROPS,and the crashworthiness of the rollover collision structure of the mount lawn mower was carried out Optimization analysis.The simulation and optimization results of the driver restraint system model show that the ROPS material is replaced with Q345,the frame is added between the rigid body structure of the car body,and the energy absorption box is added.There is no large deformation of the ROPS,which ensures that the driver's accommodation space is not violated;three schemes The 3ms acceleration of the middle driver's head did not exceed the safety threshold,and were reduced by 41.03%,38.67%,and 50.54%,respectively,which verified the effectiveness of the optimization scheme.