Analysis And Optimal Of Hydro-pneumatic Suspension Of Heavy Mining Truck Based On The Ride Comfort

Hydro-pneumatic springs are generally utilized on heavy mining trucks for itslarge loading capacity, excellent nonlinear stiffness and damping characteristic, whichcan ensure the regular driving under bad working conditions. In this paper, theperformance and optimization of hydro-pneumatic spring are simultaneously studiedfrom the perspective of the heavy mining truck’s ride comfort.A parametric nonlinear model for the hydro-pneumatic suspension is establishedwhile take a few factors such as the characters of gas, the compressibility of hydraulicoil and the check valve, and through spring force the model is incorporated into fullvehicle multi-body dynamic model, which is exactly established according to thestructure and performance parameters, and the ride comfort of full vehicle isinvestigated under random road inputs and impulse road inputs. The fitting of randomroad refers to the GB/T7031-2005Mechanical vibration-Road surfaceprofiles-Reporting of measured data. The choosing of impulse convex block refers toGB/T4970-2009Method of running test-Automotive ride comfort. The simulationresults show that hydro-pneumatic springs can help reduce vibration and improve theride comfort.The main parameters of the fore and rear hydro-pneumatic springs，such as, thediameter of the main piston, the volume and of the auxiliary gas initial position, thehydraulic diameter of the damping hole are selected as design variables. Based on therequirements of vibration and the feature of heavy sprung mass, the RMS of vibrationacceleration at driver seat and the RMS of bounce acceleration at the center of gravityof vehicle mass are selected as the cost function for suspension optimization.Meanwhile, in order to make sure a good comprehensive performance ofhydro-pneumatic spring, the optimal mathematical model is established byconsidering the working stroke, the dynamic load of wheel and the suspensionfrequency. For the optimization of full vehicle with nonlinear spring, the moving leastsquare response surface and genetic algorithm are utilized to improve the ride comfort.The obtained results indicate that the full vehicle ride comfort is improvedapproximately15.2%. It offers a good reference for the optimal design of heavymining truck’s ride comfort and hydro-pneumatic spring.