Modern control systems for vehicles often depend on accurately calculating the vehicle′s longitudinal and lateral velocities.Based on the information from yaw rate sensor,accelerometers and wheel speed sensor,the system′s state equations and measurement equations were established.The approximated velocities were calculated using vehicle dynamic model.Finally the vehicle velocities were estimated by the Kalman Filter technique and the influence of approximated velocities′ error was analyzed.Simulation results show that this method has favorable quality and small error.The reliability and validity of this method are also verified.vehicle velocity;vehicle dynamic;sensor information fusion;Kalman Filter;estimation

The interacting multiple model algorithm is used to solve the vehicle's tracking problems in automated highway system.It has multiple models,each of which matches to a particular mode such as uniform motion with constant velocity and maneuvering motion with acceleration.Combined with the target maneuvering models,the current acceleration of the target and its covariance are simulated.Significant noise reduction is achieved during the uniform motion.And it does better in maintaining the accuracy of the state estimates than the unfiltered radar measurements during the maneuver.A rapid detection of the maneuver is also obtained.The Monte Carlo simulation results show that the IMM algorithm will improve the target's tracking performance and enhance the vehicle's safety and reliability.

Based on the analysis of the system of vehicle longitudinal dynamics control,the longitude control of track homing for the platoon of the two vehicles is discussed.The second-order-control model of the longitude relative distance for a vehicle to a vehicle is presented,and the logical switch ruler between an engine and a brake is designed.The parameters of auto-adjusting fuzzy-PID control method are used by adjusting the three parameters of PID to control the varying range of error for the longitude relative distance and relative velocity between the controlled vehicle and the navigation vehicle.The stability condition of the fuzzy-PID control system is obtained using small gain theorem.The results of simulation show that,compared with fuzzy control,the parameters auto-adjusting fuzzy-PID control method can decrease the overshoot,enhance the capacity of anti-dynamic disturbance and have certain robustness.The contradictory between rapidity and small overshoot has been solved.vehicle;dynamic control;longitudinal control;parameters auto-adjusting;fuzzy-PID