Research For The Dynamic Stability Control System Of Passenger Cars Using Carsim And Matlab-Simulink

Electronic stability control(ESC)systems are well understood with regard to assisting drivers to maintain vehicle control during extreme handling maneuvers or when extreme road conditions are encountered.This paper discusses the development of a vehicle dynamics model and model validation of a BMW 5 Series in Matlab-Simulink and Carsim.A vehicle dynamics model of a BMW 5 Series created in Carsim was validated by comparing simulation results with quasi-static and dynamic test data.Bounce and Roll tests in Carsim were used to validate the suspension kinematics and compliances.The National Highway Traffic Safety Administration’s(NHTSA)Sine with Dwell maneuver was used to validate the complete vehicle model.The ESC system in this paper was designed to operate in two modes:Yaw Stability Control(YSC)and Roll Stability Control(RSC).The Yaw Stability Control used vehicle slip rate(which is the difference between actual and ideal vehicle yaw rates)as the control variable.The ESC system used differential braking to control the vehicle’s yaw and roll motions.Differential braking selectively applies individual brakes on the vehicle to apply corrective moments/forces.A simple ABS functionality was also incorporated in the model.The performance of the system was evaluated using dynamic maneuvers like the Sine with Dwell and Fishhook maneuvers.NHTSA’s Sine with Dwell maneuver is part of the Federal Motor Vehicle Safety Standard(FMVSS)126 and all ESC equipped vehicles are required to pass this test.This test was used to evaluate the performance of the Yaw Stability Control mode of the ESC system.The thesis is concluded by discussing the benefits of this model-based approach in the design of a simple,functional ESC system.The limitations are also discussed.