The Belt Fixed Points’ Simulation Analysis And The Seat’s Lightweight For Certain Automobile

This paper took one commercial vehicle which is produced by Changan Motor Corporation as the research object, and it mainly studied the strength of the seat belt assembly fixed points and the light weight of seat frame. Because the middle row seat belt fixed points were set on the seat frame model and according to the regulations, the seat belt fixed points displacement shall not exceed the prescribed RC plane in the intensity of the finite element model simulation according to the strength test requirements of the national standard GB14167-2013.For meeting the strength test requirements for seat belt assembly fixed points,a finite element model of the seat belt protection strength was established and the simulated strength was analyzed. The lightweight was designed based on the seat frame finite element model which was used for fixed point strength test. By optimizing, the weight of the frame was reduced and the stress of the frame distribute was more uniform. Meanwhile, the strength on the optimized fixed point of the seat frame was test,and the seat frame safety performance was tested step by step. This topic mainly included in the following four aspects:1.The safety-belt fixed points of the middle row seat was set up, which was mainly setting the upper safety-belt fixed points of the middle row seat,the safety-belt fixed points of the middle row seat was set on the seat frame according to the requirements for mounting position arrangement of National Standard GB14167-2013.2.The finite element model of the body, the seat frame, the human body module and the safety belt were built by the Hyper works software. In order to improve the efficiency and the accuracy, the body and the seat frame model had been simplified. The contact and the connection, the material style and the control card, the load of the loading, the parameters of the human body model and the safety model were built up as well. The finite element models were calculated by the LS-DYNA software after the safety belt had the strength of the fixed point been analyzed. The analysis showed that all the fixed points of the safety belts met the requirements of the national standard.3.After the sensitivity calculated and analyzed, the model of the seat frame was lightened. While the thickness of the seat frame model was designed as the variable, the displacement was designed as the constraint conditions and the seat frame parts with a minimum quality was designed as the objective function,the sensitivity of the finite element model was calculated. Considering the sensitivity of the parts and the actual stress, the eight parts were lightened. The total weight loss of the seat frame model was 1.22kg.4. According to the requirements for mounting position arrangement of National Standard GB14167-2013, this paper set the test condition in the seat safety test, and installed the seat belts according to the place which was designed on the simulation model, and then adjusted the loading direction. The test result showed that the strength of the middle row seat safety-belt fixed point met the requirements.