Optimal Design Of The Major Components Of The Steeling Wheel As-Sembly Of Rhombic Vehicle Considering The Fatigue Reliability

The fatigue fa ilure is the major fa ilure form o f the structures, however, the tra-ditiona l design merely focus on the statics strength ana lys is o f structure, whic h willlead to potentia l safety ha zard, and in fact, the structures are commonly under therandom dynamic load, therefore, the structure fracture alwa ys appears as the vonmiles stress far lower than the yie ld stress. To improve the design q uality o f thestructure, it is necessary to take the fatigue reliab ility into cons ideratio n in the designprocess, which can he lp attain a better d esign.The Rho mb ic Vehic le has better norma l and side crashing behaviors, sma ller turnradius, s maller drag coeffic ient, a nd it ca n also decrease the we ight o f the vehic legreatly due to its specific chass is. As the deve lop ment o f the Rho mb ic Vehic le, manyscholars have conducted a series of researches on investigating the comfort, hand lingability, crashing performance, aerodyna mics behaviors etc. Neverthe less, the fatiguereliability ana lys is of the major structures is inadequate, hence, in this paper, the keystructures of the back wheel asse mbly are ana lyzed and optimized in terms o f the du-rability performance. The ma in content of this paper is as follows:Firstly, on the occasion that it is necessity to take out the proving ground test ofthe Rho mbic Vehic le, this paper built the no nlinear finite dyna mic model of thestee ling whee l assemb ly o f the Rho mb ic Vehic le with the techno logy of the virtua lproving gro und(VPG), which has taken the ele ment choice, connectio n betweencompone nts, parameters assign o f the spring into cons ideratio n, and also generatedthe road model us ing matlab software and finite method.Secondly, to view the unite of the dema nds of the reliability test standard and thecharacteristic o f the VPG techno logy, a series of work ing cond ition a nalys is mo delshas been structured, and as a result of the exp licit formulatio n comp ute, the dyna micvon miles stress time course was ge nerated to co mpute the da mage of each work ingcond ition with the ra ins counting method and the theory o f linear cumulative dama ge,based on whic h the composite fatigue life of the crossbeam was estimated.Last, after the estimation of the fatigue life of the crossbeam, lightwe ight and a n-ti-fatigue design was carried out. Cons ideration of the fluctuation of the parameters, andtook the whee l for exa mp le, a approximate model that can represent the finite model wasbuilt in comb ination of the experimenta l design and meta model techno logy. As proved, the meta model was high-precis io n and effective. Afterwards, a deterministic optimizationand reliability-based optimization was carried out. It demonstrated that the method whichtook the uncerta inty of the design variables caused by the manufacturing process intoaccount can obtain better optimum so lutions．Proceed to the next step, the method wasused in the optimum o f the crossbeam.This paper was part of the research work of the Rhomb ic Vehic le. It proved theadvanta ge of the virtua l proving ground, and the high-precis io n, effective of the me-tamodel, and also its effic ie ncy in optimum design representing the finite model. Bycomparison of the deterministic and reliability-based optimization, it shows the ne-cessity of the cons ideration of reliability. The flow of the ana lys is and optimizationwas distinct and integrated, which can be mirrored in the forward work or other fie ld.