A Control Strategy For Active Suspension Of Emergency Rescue Vehicles Based On Road Level Estimation

It is a high requirement for emergency rescue vehicles to have ride comfort and steering stability due to the need for precision instruments and high mobility.Combining the road recognition technology with the active suspension control strategy can significantly improve the driving performance of the vehicles.Therefore,it is very important to make full use of road information to develop active suspension control strategy for emergency rescue vehicles.This paper studies on the national key research and development plan"High mobility emergency rescue vehicles(including fire fighting vehicles)professional chassis and suspension key technology research"(project number 2016YFC0802902).The paper focuses on two key issues of road surface level recognition technology and active suspension control strategy,and then a new adaptive robust control strategy for emergency rescue vehicles is proposed based on road level estimationA new T-S fuzzy controller based on RBF neural network is designed to realize road level recognition.The road estimation method takes the Relative Roughness Indicator(RRI),which is caused by different road level,as the basis of estimation,and then T-S fuzzy control rules are then designed to estimate the final road level.Aiming at the defects of TS model parameters,such as artificial experience and existence error,the RBF neural network theory and TS fuzzy control algorithm are combined to design RBF-TS fuzzy controller,which has strong adaptability.The experiment results verify the effectiveness of the road level estimation method and provide the basis for the design of the active suspension control strategy.Combining the road level estimation method with the active suspension robust control algorithm,a new control strategy for active suspension of emergency rescue vehicles based on road level estimation is proposed.The control strategy gives a parameter matrix for an adaptive optimal H_?controller from the estimated road level.And control force of active suspension is calculated to realize the adaptive control of active suspension when derived on different road levels.Experimental results show that active suspension control systems based on the road level estimation adaptively control suspension stiffness and damping by adjusting the parameter matrix of the robust controller.The proposed control strategy improves both ride comfort and handling stability in different road levels.A comparison with the passive suspension in different road levels show that,the magnitude of the sprung mass acceleration in the time or frequency domain is significantly reduced.