Simulation And Experimental Study On The Roll-over Protection Structure Of Two-post Mounted Lawn Mowers

The mounted lawn mower,which has the advantages of low noise,easy operation and high work efficiency,has gradually become an indispensable greening equipment for urban construction.However,the mounted lawn mower’s working environment is relatively complicated,and it often operates in low-lying,slope and other environments,and the uneven operating level of the staff makes the mounted lawn mower’s roll-over accidents occur from time to time.In order to protect the life and property of the driver,the most effective method is to install Roll-over Protective Structures(ROPS)on the mounted lawn mower.This article will take ROPS,a two-post mounted lawn mower,as the research object,and conduct in-depth research on its safety performance in simulation and experiment.This article introduces the development process of the ROPS safety test industry standard for two-post mounted lawn mowers,explores the main part of the current standard LY/T 2728-2016,and interprets the standard about the Deformation Limiting Volume(DLV),loading sequence,loading location,results acceptance criteria,etc.Analyze the test procedure of the safety test in the standard,and design a load distributor suitable for the ROPS safety test conducted in this paper.The basic theory of the finite element method and the elastic-plastic finite element analysis process are summarized.According to 2D drawings,drawn a 3D model of two-post mounted lawn mower’s ROPS.HyperMesh is used to simplify the 3D model of ROPS,and according to the basic principles established by the finite element simulation model,the mesh is divided and the material is assigned,At the same time,the load distribution of the simulation model was carried out according to the force of the ROPS in the actual test.The created simulation model is imported into ANSYS,and the nonlinear finite element calculation is performed on the simulation model to draw the load-displacement curve loaded by the simulation model.To explore the nonlinear finite element calculation results,and comprehensively analyzed the stresses and displacements of the longitudinal loading,side loading,and vertical loading of the ROPS simulation model,and in-depth analyzed the structural stress concentration and local plastic deformation.Set up a ROPS safety test bench according to the standard,and properly install the test equipment and instruments used in the test.The test method in LY/T 2728-2016 is used to carry out a safety test on ROPS in the order of longitudinal loading,side loading,and vertical loading,collect test data,and draw the load-displacement curve of the ROPS loading test.During safety test,DLV was not invaded or out of ROPS protection.The loading force does not show a downward trend during the test,so it is not necessary to perform an energy absorption overload test.Comparing the results of the nonlinear finite element simulation and the safety test of the ROPS simulation model of the two-post mounted lawn mower,the deformation size and deformation position of the two are similar,and the load-displacement curve trends are approximately the same,which comprehensively demonstrates the effectiveness of the simulation model,and it proves that the simulation analysis method in this paper is feasible and can be used for the research of other similar structures.