Research On Ride Comfort Of Multi-axle Emergency Rescue Vehicle

Emergency rescue vehicles need to maintain high mobility and high reliability under complex road conditions in order to meet the mission requirements of disaster relief and rescue.Therefore,they have higher performance requirements for the suspension system.Compared with the traditional passive suspension system,the active suspension system can control the body posture in real time,which can meet the requirements of the emergency rescue vehicle to keep the body posture stable in the process of driving.Combined with the national key R & D project "Research on Key Technologies of Special Chassis and Suspension for High-mobility Emergency Rescue Vehicles(Including Fire Fighting Vehicles)"(2016YFC0802902),this paper aims at the problem that emergency rescue vehicles need to keep their body posture stable when they are moving,the active suspension actuator control method and body pose stability control strategy are studied systematically and deeply.The main research work of this paper is as followsConsidering the actual problems of active suspension system parameters such as time variation,external interference,model nonlinearity and actuator output saturation,a dynamic model of one-sixth vehicle active suspension system is established.The sliding mode control law is designed according to the sliding mode control theory,and the unknown parameters in the sliding mode control law are estimated in real time by combining the adaptive control theory and the approximation characteristics of the fuzzy system.An adaptive fuzzy sliding mode controller of the active suspension is designed,and by establishing an anti-saturation dynamic auxiliary system,the adverse effect of the actuator output saturation constraint on the vertical motion control effect is eliminated.The dynamic model of active suspension hydraulic actuator is established,and the Fractional Order PID controller is designed to realize the force tracking control of the hydraulic actuator.The parameters of the Fractional Order PID controller are optimized by using the Beetle Antennae Search Algorithm.The simulation results show that the method can effectively improve the force tracking performance of the active suspension hydraulic actuator.An adaptive fuzzy sliding mode controller for vehicle active suspension system is designed.Aiming at the problem of vehicle body attitude stability control,the vertical,pitch and roll stability controller are designed respectively,and the output force of six sub suspension system actuators is solved by static decoupling.The simulation results show that the control method can not only stabilize the vehicle attitude under the condition of uncertain parameters and external interference,but also solve the problem of actuator output saturation.