Adaptive Cruise Control: Design And Simulation

Adaptive cruise control (ACC) system belongs to active securitytechnology. ACC distinguishes itself from cruise control in adding thefunctions of headway distance control and collision warning. It aims atreducing the workload of driver and traffic accidents, as well as increasing thetraffic flow throughput and making the driver more comfortable. AlthoughACC supplies a driver assistant in driving, the driver still needs to concentrateon the road status.According to the previously setting parameters and tracing the speed ofpreceding vehicle, the ACC system can adjust the traveling speed in order tomaintain a security distance between an ACC-equipped vehicle and apreceding vehicle. It is also one of the most important automatic drivetechnologies in Intelligent Transportation Systems (ITS), which is calledAdvanced Cruise-Assist Highway System (AHS).After having analyzed the previous ACC algorithms, this paper developsan integrated solution, which is based on fuzzy PID. In the meantime, itpresents a feasible controlled procedure, as well as the particulars and thesimulation results of each module.In this paper, there are some improvement and innovation in controltechnology research and application of the computer. In controller structure ofthe throttle, it proposes "the positional output controller with incrementalalgorithm kernel", which can smoothly switch between the speed trackingcontrol mode and the distance tracking control mode. An innovative controllerbased on fuzzy and PID control is also presented for the distance-trackingcontrol mode, which is called "Fuzzy-PID controller with coefficientadjusting". This algorithm has some advantages of PD type fuzzy controller,such as robustness, simple design and independence on accurate mathematicsmodel. The PI controller can eliminate steady state error, and the adjustmentof PI controller's coefficient can also effectively restrain oscillations andlimit cycles near the set point.The rear-end collision warning/avoidance (CW/CA) system algorithm isdeveloped. The detail of how to improve algorithm is analyzed and deduced inthis paper. The new algorithm is more safety than the previous algorithms.According to the documentaries, Matlab/Simulink is used to rebuild thevehicle longitudinal dynamics model. Some simulation analyses are broughtout to validate the rebuilt model. We can assert that the characteristics ofrebuilt model are the same as those of original model.Finally, the simulations analyses have been done to test the ACCcontroller. The comparative results show that the developed algorithm is moresafety than the previous algorithms, the switch from the speed-trackingcontrol mode to the distance-tracking control mode is smooth, and the vehiclecontrol is rapid and accurate on the tracking status. This design is successful.