Dynamic Simulation And Experimental Investigation On Falling Object Protective Structures Of Engineering Vehicle

The function of the Falling Object Protective Structures(FOPS) is to protect driver from the accident caused by the impact .Because of the flexibility as well as rigidity of the FOPS, it can not only stand the crash but also absorb the energy through its deformations, as a result it can evidently reduce the damage to the passengers. With the advanced request for the security of engineering vehicle in the world, FOPS is becoming the forced demand in more and more country. At the same time, in our country, there are more and more project about the security capability verification of FOPS is under developing. On the bases of systematic summarization on the critical problems, research methodologies and research outcomes in the area of impact research home and abroad, the dissertation,on the one hand, analysises the more important problems in the mathematic modeling as well as the simulation and has given the relative methods to solve these problems.On the other hand ,it has determined its main research targets as the most relatively displacement of FOPS relative to DLV and the research objects are also broadened to the research of energy absorption characteristics for FOPS during the process of falling object impact. To verify CLG856 wheel loader's FOPS, the laboratory tests have been performed according to ISO3449:1992 (Earth-moving machinery-Falling -object-protective structures-Laboratory tests and performancerequirements) and ISO3164:1995(Earth-moving machinery-Laboratory evaluations of protective structures–Specifications for deflection-limiting volume). By tests results, the crashworthiness of FOPS have researched and evaluated. The falling object impact FOPS is a problem with three-dimension nonlinear large deformation and structual dynamics. The author has made detailed analysis to the large plastic deformation dynamic characteristics for the top cover of the FOPS under low impact speed, which explicitly present the essence of the inherent plastic dynamic features of the FOPS. Computer simulation is one of the most important ways to research the modern impact problem. In this article, the dynamic character of FOPS is mainly focused, as well as the performance of the FOPS energy-absorbing under low speed impact...