Dynamic Simulation And Design Optimization Of A Low-end SUV At A High Speed

Low end SUV is taking up a high share of all SUV in Chinese market at present, but its technology has a little rough comparing with other SUV and its performance is lower. Mainly car ride comfort and handling and stability have been significantly affected when car is at a high speed, causing decrease of passenger comfort and active safety performance. Recently research work of improving car ride comfort and vehicle handling and stability, especially when at a high speed, is paid more attention. For another thing, along with the rapid development of computer technology, based on the multi-body dynamics analysis software become more and more common in the field of automotive design and R&D.In this paper, a low-end SUV was researched. Firstly, air resistance coefficient and rolling resistance coefficient of SUV were obtained by using of sliding experiment. The car’s three power indicators were calculated with Excel software. Then a prototype car’s subsystem (mainly including suspension systems, steering system, tires and body systems) were created in ADAMS/Car according to size and parameters of car. All subsystems were assembled in ADAMS/Car standard interface and multi-body dynamics model was got after debug.In order to verify the accuracy of the model, a suspension biased simulation was carried. The result of simulation and experiment was found in good agreement. Then according to car ride comfort test in accordance with state standards, a low speed and high-speed ride comfort simulation under a random B-class road were carried. Last, result was input to a ride comfort evaluation software and show that the car ride comfort need to be improved.According to vehicle handling and stability methods in accordance with the nation standard experimental, simulation of pylon course slalom test, steering wheel angle step input test and return-ability test were carried. Results illustrated that performance of return-ability need be improved when car is at a high speed.Structure of SUV’s torsion bar double wishbone suspension was optimized in the passage, and then optimization model was simulated and analyzed again.The result showed that low end SUV ride comfort was increased by4.5%and6.2%in performance of steer release when it was at a high speed.