Research On Passenger Car Ride Comfort Based On ADAMS

With the development of science and technology level, people living standard rise, the related public transportation in aspects of the design requirement also more and more high, especially the riding comfort be closely related to driving smoothness performance is becoming a hot spot of research now. My paper based on multi-body system dynamics theory and established the motor vehicle dynamics model, module of ADAMS/Car as research tools. Respectively in different roads for ride comfort simulation experiment of automobile,and according to the front and rear suspension spring stiffness and damping as a design variable to optimize ride comfort analysis.First, using the multi-body system dynamics software ADAMS/Car modules, the whole vehicle dynamic model is set up, which including front and rear suspension system model, steering system model, the front and rear stabilizer bar model, powertrain model, the braking system model, car body system model, tire model.Second, according to national standard GB/T 4970-4970 "vehicle riding comfort test method" regulation, bus test points located in the driver side and close to the above the seat of rear axle nearby, this paper selected the test point on the surface of seat number 16 of bus.Third, under different road surface and the speed of the car to the ride comfort simulation analysis of random road respectively, get surface of thenumber16 seat above the rear axle three axial vibration the root mean square value of weighted acceleration and the total weighted acceleration root mean square value. When on the random asphalt pavement and in the speed of 70 km/h, surface of number 16 passenger seat of the root mean square value of weighted acceleration will be more than 0.315 m/s2, to cause the body some uncomfortable feeling. If reach speed of up to 50 km/h on the random gravel road surface, number 16 passenger seat surface root mean square value of weighted acceleration will be more than 0.315 m/s2.When we do the Impulse test about the vehicle on convex block pavement under different speed, number 16 seats at the surface of the vertical acceleration peak value has not been reached between the extent of the damage to the human body. So in this paper, the optimization goal mainly is reduce the acceleration that car body is passed to the human body.Fourth, using ADAMS/Insight module optimize analysis,according to passenger car front and rear suspension spring stiffness and damping design variables for optimization. Determine the influence degree of the design variables to the objective function by sensitivity analysis: front suspension spring stiffness Kf>after suspension shock absorber damping Cr> front suspension shock absorber damping Cf>after suspension spring stiffness Kr. Adjustments according to the sensitivity analysis results before and after the suspension stiffness and damping of the match and get the optimal value, Before hanging spring stiffness frame stiffness decrease from 150N·mm to 120N·mm, suspension stiffness after 170N·mm unchanged, front suspension damping decreased by 11.79N·mm·s-1 to 9.44N·mm·s-1, after the suspension damping increased by 11.84N·mm·s-1 to 14.21N·mm·s-1.Fifth, test verification. Will be changed after the suspension spring stiffness and damping values into the model, again vehicle ride comfort simulation analysis according to 30 km/h to 80 km/h speed on random asphalt and gravel road surface, After the optimized total root mean square value of weighted acceleration fell respectively by an average of 16.55% and 16.55% on number 16 passenger seat surface. This indicates that after the optimized bus comfort has been improved to a certain degree of.In a word, The researches of this article identified a vehicle ride comfort based on virtual prototype technology analysis and evaluation method, through the simulation test to evaluate the vehicle ride comfort, and then discusses the vehicle ride comfort of the improvement scheme. The evaluation results indicate that: the vehicle ride comfort under medium and low speed is good, while under high speed will be improve better, this is consistent with the actual situation; The study results of improvement scheme show that: For bus front and rear suspension spring stiffness and damping values of reasonable modified and matching can significantly improve vehicle ride comfort obviously.