Research On Integrated Braking Strategies For Multi-axle Heavy Duty Vehicle

All-terrain cranes have some features of large weight, high speed, long body and multiple axes. As the lack of integrated management of the braking system and the various braking sub-modules are independent, braking performance has not been fully realized. Some accidents, such as off the road, occur frequently so that vehicle running safety is influencedIntegrated braking management system of multi-axis heavy vehicle optimize the brake of vehicle moving, parking brake, a variety of auxiliary brake and brake gear, to dynamically allocate capacity of various forms of braking and braking torque of wheel, and improve safety and reliability performance of brake.In the pneumatic suspension system, the model of hydraulic oil, accumulator, orifice, piping and single-axle pneumatic suspension system are build and tested in the bench. The attachment coefficients of each axis in conditions of different braking intensity during braking with the vehicle fully loaded are computed.In the air brake system, the performance of some key components of braking, such as foot braking value, the foot relay valve, differential relay valve, four-circuit protection valve are measured in bench. The air brake system virtual prototype mode of integrated vehicle is build.In the auxiliary braking system, these models of engine retarder brake, gearbox assist brake, and eddy assist brake are briefly discussed. The model of integrated vehicle retarder is established using Simulink tool, and braking performances in condition of the flat road and slope road are obtained.The management architecture and control strategies of braking system are studied. Respectively the management strategies to auxiliary brake, braking during vehicle moving, emergency/parking brake and brake lights are researched and all-terrain crane brake system security management processes is provided.The performance of vehicle integrated braking management system were validated by using experimental vehicle under different road conditions. the rest results showed that the system could optimize the brake of vehicle moving, parking brake, a variety of auxiliary brake and brake gear, dynamically allocate capacity of various forms of braking and braking torque of wheel, slow down and stop vehicle with stable manner within a reasonable time and distance, reduce the accidents of off the road, improve braking efficacy and vehicle running safety.