Safety Performance Research And Lightweight Design Of ROPS&FOPS Structure Of ET66 Excavator Cab

On the basis of summarizing the research on the safety performance of ROPS&FOPS structure and lightweight technology at home and abroad,the paper aims at the structural characteristics of the ET66 excavator cab produced by Jiangsu Benyu Company and the requirements for the safety performance of the excavator cab in the national standard.The ROPS&FOPS structure of the engine cab has been simulated,analyzed and verified.On this basis,an automobile lightweight evaluation method is introduced to analyze the ROPS structure,and a lightweight evaluation method for the ROPS structure of the excavator cab is proposed.Based on this,the multi-objective lightweight design of the ROPS structure of the ET66 excavator cab is carried out.The main research contents of the thesis are as follows:1.Based on the general situation of ROPS&FOPS structure safety performance research and lightweight of excavator cab at home and abroad,the basic theory of ROPS&FOPS structure safety performance simulation and multi-objective optimization theory of excavator cab are introduced and explained.2.Established the ROPS&FOPS structure finite element model of the ET66 excavator cab based on the finite element modeling method through Hypermesh software,and the material properties of the Q235A and Q345B material samples provided by the manufacturer were subjected to tensile tests.Then,according to the national standard on the safety performance requirements of the ROPS&FOPS structure of the excavator cab,a finite element simulation analysis was performed to obtain the displacement and stress cloud diagrams and relationship curves of the ROPS&FOPS structure of the excavator cab under each performance requirement.3.Based on the determination of the DLV position in the national standards GB/T 17772-1999,GB/T 19932-2005,and GB/T19930.2-2014,the loading position and performance requirements of the ROPS&FOPS performance test of the excavator cab.According to the requirements of the national standard,the ROPS&FOPS structure of the ET66 excavator cab is subjected to a performance loading test,and the load-displacement relationship under the test load is obtained.The simulation results and test results are compared and the main reasons for the errors are analyzed.4.According to the lightweight coefficient of passenger car body-in-white,an evaluation method for the lightweight coefficient of the ROPS structure of the excavator cab is proposed.According to the problem of multiple parameters in the coefficient,a multi-objective optimization method is selected.Establish a lightweight multi-objective optimization design model for the ROPS structure of the ET66 excavator cab,perform sensitivity analysis on the design variables,select the final design variables,use the optimal Latin hypercube sampling test design method to establish the RBF neural network approximate model,and finally adopt the Insight software The NSGA-II algorithm performs multi-objective optimization.Then,the performance comparison before and after optimization was carried out.The comparison results showed that the lightweight coefficient of the ROPS structure of the cab was reduced by 10.89%,and the lightweight effect was significant.