Research On Active Suspension Control Strategy Based On Adaptive Impedance

Emergency rescue vehicles,as the backbone of land rescue at the scene of accidents and disasters,need to cope with complex and variable driving conditions.Due to the installation of passive suspension system,their driving performance is poor,and reduces the rescue efficiency.Active suspension can actively adjust suspension parameters based on the real-time state of the vehicle,so its application to emergency rescue vehicles can greatly improve the rescue efficiency.Therefore,this paper studies the active suspension control strategy of three-axis emergency rescue vehicles with electro-hydraulic servo actuators.The specific research contents include:Due to the complexity of active suspension control algorithm based on force control and the difficulty in implementing,the active suspension control strategy based on position control is proposed.The strategy is implemented based on dual loop control.The function of outer loop is to calculates the expected telescopic displacement of each suspension actuator according to the vehicle state,and the function of inner loop is to use electro-hydraulic servo actuators to achieve the adaptive impedance control based on position.In order to ensure the performance of the overall control algorithm,first of all,the high-precision position tracking of electro-hydraulic servo actuators is studied,and an adaptive control method based on a strict feedback model is proposed.This method is used to simplify controller design while avoiding model reduction.On this basis,an adaptive method is combined to estimate the unknown boundaries of external load disturbances and uncertain parameters in the actuator model online to improve the position control accuracy and anti-interference ability.Secondly,the control algorithm for the overall suspension system of a three-axis emergency rescue vehicle is studied,and an adaptive impedance control method considering posture compensation is proposed.This method combines the posture deviation control principle and the adaptive impedance control method,which can maintain a stable body posture while effectively reducing the dynamic load of the vehicle,to improve the ride comfort and attitude stability of the vehicle.Finally,in order to verify the control effect of the active suspension system control strategy proposed in this paper,an electro-hydraulic servo position control test platform and a three-axis vehicle active suspension test platform were built respectively.Through simulation and experimental verification,it was concluded that the position tracking algorithm proposed in this paper can effectively improve the position tracking performance of the electro-hydraulic servo actuator compared to traditional control methods;The proposed vehicle active suspension control method significantly reduces the peak to peak value and standard deviation of vehicle attitude under typical bump road impact compared to passive hydro-pneumatic suspension.