Automobile Ride Robust Optimization Based On A Mini-bus

In the recent years, our road construction has achieved remarkable results. It makes car travel more convenient and faster, travel time by car also became longer. Long time travel requests more stringent ride comfortable. Ride comfort plays an important role in the market competition.Domestic automobile engineers have done a lot of investigations in automobile ride optimization and obtained considerable researches. But at present, the simulation and optimization of ride just aims on one or several countable typical operating cases. Vehicle driving cycle is complex and changeable, so the simulation and optimization should consider different operating cases too. Automobile ride varies with the speed, road conditions and load change. Optimization results for a single design condition obviously can't meet the rising requirements of the market. In order to solve this problem, a new ride optimization has been developed by adopt six sigma robust optimization design method which consider the vehicle speed, load and road irregularity as the factor and noise as the optimization target.A mini-bus has been taken as the research object. To analysis the mini-bus ride performance, the muti-body model of the mini-bus has been built using ADAMS software. The model accuracy has been validated by suspension kinematics analysis, and the ride performance of the vehicle has been evaluated according to GB/T4970-1996 and GB5902-86. The ride performance of the vehicle in typical load cases has been optimized by response surface methodology based on DOE; the optimal suspension parameters in each single load case has been found, and then the law of optimal suspension parameters vary with speed and load has been found. After all, six sigma robust optimization design method has been adopted to optimize the suspension parameters of the car by defining the speed, load and road irregularity as factor of noise. A new method has been developed based on six sigma robust optimization for automobile ride optimization. The ride performance of the mini-bus has been evaluated by Monte Carlo method prior to optimization, after optimization in typical condition and after robust optimized. To further validate the feasibility of the method, the result has been put back to muti-body mobiles to analyses the ride performance. Those results all shows that after robust optimization, the ride performance of this car has improved especially for complex conditions. So this method is useful, it give an orientation for this mini-bus improvement.