Research On Vehicular Platoon Control Based On Sliding Mode Control

With the gradual increase in the number of cars,the development of intelligent transportation has become a way to alleviate road congestion,reduce traffic accidents,and reduce environmental pollution.Vehicular platooning can greatly improve efficiency and safety of highway systems.The driving vehicles are affected by some external disturbances such as wind speed,parameter uncertainty,air resistance.Moreover,owing to the physical limitations of the vehicle,the device such as sensors and actuators is inevitable fail of aging or damage in practical engineering applications vehicle.These factors can lead to a certain challenge to vehicular platoon control.Therefore,how to realize the stability control is particularly important to vehicle platoons according to the different external conditions suffered by the vehicle platoon.The main research work and contributions to the dissertation are summarized as follows:First,establish a specific vehicular platoon model for the heterogeneous autonomous platoons subject to external disturbances.Considering the influence of the uncertainty of vehicle dynamics and the complexity of vehicle states measurement of vehicular platoon performance,an extended state observer is designed to estimate the state of the vehicle system and external disturbances.Combining the information about the extended state observer,the sliding mode controller is designed to achieve the stability of the individual vehicle and string stability,which does not rely on an accurate mathematical model.The finite-time stability of the control strategy and the effectiveness of the proposed method is verified by numerical simulations.Second,a second-order vehicle platoon control model is established including parameter uncertainties,actuator faults,and external disturbances.A finite-time exact disturbance observer with high accuracy,low chattering,and fast convergence is proposed to estimate and compensate for the effects of uncertainty and actuator faults on vehicle platoons.A recursive sliding mode control algorithm is designed to control the heterogeneous vehicle platoon system based on the constant time headway policy,the stability of the individual vehicle,and the string stability is proved by the establishedLyapunov function.Third,considering a more practical third-order vehicle control model,a vehicular platoon control strategy is developed in the presence of actuator faults,uncertain parameters,and complex unknown disturbances.In addition,in order to estimate and compensate for complex environments,an extended state observer is designed.Based on the modified constant time headway policy,a dual-layer adaptive super twisting integral sliding mode controller is designed to enable the vehicle platoon system to reach a stable state in a finite time.The adaptive super twisting algorithm overcomes the phenomenon of chattering and overestimation.The effectiveness of the proposed control scheme for an interconnected vehicle platoon system is demonstrated by establishing a Lyapunov function.