Study On Lane-change Assistant Strategy Of Multi Mode Adaptive Cruise Control

In order to adapt to the urban complex traffic environment,a multi-mode adaptive cruise control strategy with lane-changing assist control is proposed.In the upper-level controller,six modes strategy is designed,including constant-speed cruise,steady following,approaching/lane changing,strong acceleration,strong deceleration and collision avoidance mode.According the different demand of each mode for the comfortable performance,tracking performance and safety performance,the parameters of each model are defined.Then the mode switching rule is set up to choose the approapriate mode.In the lower controller,the PID control plus look-up tables are adopted and the transition zone between the throttle and braking controller is designed.Next,a lane change assistant policy is proposed.If possibility of lane change and action of lane change are detected when the host vehicle gets close to the preceding vehicle,the lane change assistant policy will maintain the velocity of the host vehicle instead of decelerating.The lane change assistant policy is verified under three dangerous conditions,then a series of empiric value is obtained which can identify the lane change intention and judge the lane change possibility.Finally,three scenarios of urban complex conditions are designed,the multi-mode adaptive cruise control strategy with lane change assistant policy is verified by Matlab/Simulink,Carsim and dSPACE.The results show that the control strategy is rationally designed,the switching mode is appropriate.The actual acceleration satisfies the acceleration characteristics of the transient mode and the steady state mode and the control strategy enables the vehicle to realize the stop&go function on different ramps,which indicates the strategy has robustness.The dangerous lane change scenarios simulation indicates that the strategy can identify the lane change intention and judge the lane change possibility,which can obtain higher velocity and improves the acceptability of the strategy.