Heavy Vehicle Dyanmics Modeling And Rollover Warning Simulation

With the development of automobile industry for more than a century,automobile has become the pronoun of high-tech,modernization and skill.Cars,which witness the changes of human science and technology again and again,not only achieve the goal of the high speed movement,but also satisfy human compact life at the same time.For this reason,automobile is not only a means of convenient transportation,but into every aspect of people's life quietly.With the implementation of made in China “2025”,heavy trucks as the mainstay,which undertake the mission of accelerating the economic development,brought many challenges for engineers.Heavy-duty vehicle has the characteristics of long development period,high cost of research and development,high risk of test operation,and makes the dynamic simulation of heavy vehicle become a key part of experimental test under the limit condition.But at present,most of the dynamic simulation software for a number of medium mechanical properties of heavy-duty vehicle nonlinear oil and gas suspension targeted poor,resulting in simulation data is not accurate,so that the simulation becomes meaningless.In addition,heavy vehicles in the event of traffic accidents can easily lead to death and huge property losses.Therefore,to solve the heavy vehicle dynamics simulation accuracy and driving safety as designers need to solve the problem.In order to solve the problems of heavy vehicle simulation and driving safety.Based on the theory of multi-body dynamics and the fractional-order model of oil-air suspension,this paper constructs the 22 degree of freedom dynamic equation for heavy-duty vehicles.At the same time,this paper combined with the current domestic and international variety of rollover warning algorithm,based on heavy vehicle driving state equation to build the rollover warning algorithm.Through the acquisition of vehicle driving state parameters real-time prediction of vehicle dynamic warning time,to improve the safety of heavy vehicle driving purposes.The research works in this thesis is stated mainly from the following aspects:1.Aiming at the XCA60 heavy vehicle,based on the nonlinear oil-air suspension model and the Calspan tire model,the modular dynamic differential-algebraic equation for the twenty-two degrees of freedom of heavy vehicles is constructed.2.This paper has designed a heavy vehicle rollover warning algorithm based on the static equation which obtained from static parameters and determine a criterion that is according to the Routh-Hurwitz criterion and LLT criterion to establish vehicle anti-interference stability conditions and dynamic balancing stability conditions.3.The article simplify the vehicle dynamic model into the class ?mathematical model based on using Boolean matrix to improve the eliminated method,which can achieve the goal of calculating the differential algebraic equations quickly.4.This paper describes the composition and principle of manipulating the simulation system.The XCA60 heavy vehicle is used as the research object to establish the mathematical model of the transmission module and the steering module,and the vehicle dynamic simulation system with visual interface is set up.5.The accuracy of the dynamic calculation,the feasibility of the rollover warning system and the substitutability of the whole system for the actual vehicle are evaluated by the vehicle simulator test platform.