Design Of Vehicles Dynamics Solver Of Automobile Driving Simulator

This issue is the part of an objectives of the international cooperation project: "Next-Generation Math-Based Virtual", As the project is to develop an integrated model parameter settings, simulation, analysis of integrated environmental software - NGCar, and require software to conduct joint simulation with Simulink.The NGCar uses vehicle dynamic simulation of the 29 DOF vehicle dynamic model of the State Key Laboratory of Automobile Dynamic Simulation. This is contribute to the development of the 29 DOF vehicle dynamic model in simulation of vehicles. The development of Solver is also an important component of development work.In this paper, a great deal of research, analysis of solvers and the methods of joint simulation with other software about a number of mainstream vehicle dynamics simulation software have been made, and the base theory, implementation, scalability of the vehicle dynamics simulation software etc. has been collated.The functions and the motheds of implementation of CarSim solver have been analysed in detail. CarSim solver follows VehicleSim Interface Specification of the MSC dynamics solver. VehicleSim interface specification has elaborate documents, this maks CarSim easier for user as a second development platform. The CarSim solver has achieved the curve fitting of test data and the control of dynamics simulation at the same time, and the user-defined calculated variables and user-defined function calls have been achieved, which carrie out the hardware-in-the-loop simulation. It is the base of design and implementation of the Simulink interface that understanding and grasping the mechanism of Simulink engine. In this article a detailed study of the mechanism Simulink engine has been made, by analyzing the callback function of the function in the Simulink engine initialization and iterative process of simulation. Understand and grasp the working principle and the working process of Simulink engine is the foundation on the Simulink simulation.Designed NGCar solver: ASCLSolver to meet the needs of software, and build a parameter name-address mapping table. Through the name-address mapping table to obtain the parameters of address, the parameters of the dynamic model can be read and write. And the engine to solve expression has been designed using least squares method for fitting the test data on the kinetic parameters. By the way of callback function to provide the interface for users to add their own functions. Then user modules and hardware in-the-loop simulation can be achieved.About joint simulation, the solver can be packaged by the S-function.The Simulink simulation of the interface program of the ASCLSolver named ASCLWrapper has been designed and implemented, and established the Simulink model which contains ASCLWrapper.Finally, the program validates by simulation test. Use the Pylon Course Slalom Test the operation of the driver in field test as the model simulation input, while add a new variable by expression in the simulation process terms, and output the simulation results. Verified correctness of ASCLSolver and interface program ASCLWrapper, meet the software design requirements.