Quantitative Evaluation on the Braking Stability of the Composite Braking System Composed of a Retarder and a Service-brake System

To quantify the effect of retarder on the braking stability of automobiles,an adhesion coefficient model was built for the composite braking system composed of a retarder and a service-brake system.The stability of the composite braking jointly provided by the retarder and the service-brake system was evaluated by the model and the standard of ECE R13.The evaluated results show that the composite braking stability decreases gradually with the increase of the braking force from the retarder;To improve composite braking stability,the braking power distribution coefficient of the service-brake system was adjusted by the position relationship among the braking power distribution line of the service-brake system,the generalized braking force distribution line and the generalized I curve,and the constraints from ECE R13.Simulation results show that the composite braking stability is improved significantly.