Pneumatic ABS Modeling and Failure Mode Analysis of Electromagnetic and Control Valves for Commercial Vehicles

A failure of the pneumatic ABS (anti-lock braking system) weakens the braking performance of commercial vehicles. It affects the driving safety of vehicles. There are four typical failure modes that include: the failure of the pilot inlet solenoid valve and pilot exhaust solenoid valve of the pressure regulator, the failure of the series dual-chamber brake valve, and the failure of the relay valve. In order to study the braking performance and the rule of vehicles under the failure modes of the pneumatic ABS, the co-simulation model of the pneumatic ABS of the commercial vehicle was established based on AMESim and Simulink softwares. The gas path subsystem of the pneumatic ABS and the vehicle model were built based on AMESim. The controller was established based on Simulink/Stateflow. The data were transmitted between the AMESim and Simulink software by using the data interface block. The co-simulation model was validated by tests. The results showed that the maximum error of the braking deceleration is 13.51%. The model can simulate the braking process of the vehicle well. Based on this, the four typical failure modes of the pneumatic ABS were simulated, and the influences of different failure modes on the braking ability were analyzed. The influence of failure ratio on braking distance in four modes was obtained. It can be seen from the simulation results that the failure of the pilot inlet solenoid valve and the pilot exhaust solenoid valve of the pressure regulator cause the wheel lock. The failure of the lower chamber of the brake valve and the failure of the relay valve have a great influence on the braking distance.